WO2025119394A1 - Microfluidic liquid path structure, and device comprising same and operation method therefor - Google Patents

Abstract

A liquid path structure and an operation method therefor. The liquid path structure comprises: a first wall surface (1); a second wall surface (2), configured to be disposed close to the first wall surface (1) or to be disposed in at least partial contact with the first wall surface (1), wherein the space between the first wall surface (1) and the second wall surface (2), where the two face each other, forms a flow domain (3), and the flow domain (3) comprises a thin flow domain; an inlet structure, configured to comprise one or more inlets (4) which are communicated with the flow domain (3) during operation, allowing a fluid comprising at least a first fluid to be introduced into the flow domain (3); and an outlet structure, configured to comprise one or more outlets (5) which are communicated with the flow domain (3) during operation, allowing the fluid passing through the flow domain (3) to be discharged. The first fluid is configured to be capable of receiving applied energy.

Description

Microfluidic liquid path structure, device including the liquid path and operation method thereof

This application claims priority to the application number 202311673673.9 filed with the Patent Office of China on December 7, 2023, and the invention name is "A liquid circuit structure, a device comprising the liquid circuit and an operating method thereof", all contents of which are incorporated by reference into this application.

Technical Field

The present application relates to a liquid path structure for constructing a novel flow field and an operation method thereof, and in particular to a manipulation and replacement process of a tiny amount of liquid.

Background Art

Traditional biochemical electromechanical devices usually use macroscopic amounts of fluid when it comes to fluids. For example, medical equipment uses a whole tube of reagent to test a sample, or the chip is directly connected to pure water with a pipe to rinse the surface and the chip is soaked in a pool of chemical reagents for reaction and cleaning. This causes two problems:

1. Expensive and requires a large amount of reagents;

2. Performance may be poor because mass transfer in bulk liquids is always slow.

According to Whitesides’ review paper, “Microfluidics is the science and technology of systems that process or manipulate small volumes (10^-9 to 10^-18 liters) of liquids, using channels that are tens to hundreds of microns in size. The first applications of microfluidics were in analysis, where it offers many useful capabilities: the ability to separate and detect with high resolution and sensitivity using very small sample and reagent volumes; low cost; shorter analysis times; and a small footprint for analytical equipment. Microfluidics exploits its most obvious property, its small size, as well as some of the less obvious properties of liquids in microchannels, such as laminar flow. It offers fundamentally new capabilities in controlling the concentrations of molecules in space and time.”

As a technology, microfluidics is almost too good to be true: it offers so many advantages and few disadvantages in its primary application (analysis). However, it has not yet been widely used. Some of the key reasons for this include:

1. Developers and even users need certain background skills to develop and use (such as fluid-related skills);

2. The supporting accessories of microfluidic chips are numerous and complex, and they require related accessories to work, such as pumps and valves;

3. The number of manufacturing steps is large, resulting in higher costs and lower yields;

4. The size of the pipeline is small, and the products produced require strict quality control, otherwise the coefficient of variation (CV value) will be too high and the results will be inaccurate.

Specifically, when the pipeline size is small, even a small size change will lead to a relatively large change in the microstructure size (for example, if the size of 50 microns changes by 50 microns during production, the change is 100%, while if the size of 1 mm changes by 50 microns during production, the change is 5%), resulting in the coefficient of variation (CV value) of the result being too high, and the intra-batch and inter-batch differences being large.

Microfluidic technology confines the reaction to a chip. Although the channel is micron-scale, it consumes less reagents, has fast mass transfer and rapid reaction, traditional microfluidic technology requires the construction of a three-dimensional liquid channel to constrain the flow of the liquid. The height and width of the channel are microscopic, and the flow direction is macroscopic. In order to provide energy to offset the friction of the liquid moving in the microchannel, the entire system usually needs to be encapsulated, and a pump-type fluid device is used to continuously provide pressure to push the fluid and prevent leakage. This makes the system have many components and the pipeline is difficult to clean, resulting in increased consumption of reagents. In addition, if pressure is not used for driving but passive methods such as capillary force are used, the device is more difficult to control and is usually used in simpler detection. Although microfluidic devices save reagents, the chip cost is high; at the same time, both research and development and production are difficult, so it has not yet been widely popularized; in addition, the pipelines used to connect the chip are macroscopic, which makes some reagents consume a lot, thereby partially offsetting the advantages of microfluidic devices.

The higher threshold but no performance improvement over existing solutions has resulted in a limited number of microfluidic devices on the market. The most common ones are either simple in structure and cheap, such as antigens or pregnancy test strips, or have higher added value, such as DNA sequencing chips.

For example: Illumina's flow cell system for gene sequencing, and Roche's Cobas Liat system for nucleic acid detection.

Summary of the invention

In order to solve the above problems of microfluidic technology, the present application provides a technology, which includes a Couette-like flow field construction method, a construction device and an application in the field of microfluidics. Considering a product is usually divided into several main aspects such as reliability, performance, and cost. The technology of the present invention absorbs the advantages of traditional biochemical electromechanical equipment and microfluidic equipment, maintaining the reagent saving and rapid reaction of microfluidic equipment, and having the effects of stability, reliability and easy manufacturing of traditional equipment, so it is expected to replace both.

In order to solve at least one of the above problems and/or other potential problems of the prior art, it is necessary to invent a new fluid driving method and its hardware platform. Our technology is called the Couette-like flow field construction method, and the related hardware platform is called the shear-driven fluid platform. It mainly uses the shear force of the fluid to construct a flow field similar to the Couette flow field, which is used to replace the traditional method-the Poisson leaf flow field that uses pure pressure drive to overcome the friction between the fluid and the solid wall surface that constitutes the thin flow domain. The purpose of this design is first to use a small amount of fluid to achieve rapid surface cleaning and replace the liquid originally existing in the flow domain, saving costs. Secondly, there are fewer parts involved, eliminating complex seals and pipeline valves, and increasing reliability. Third, the quality control of the device becomes simpler because the number of parts is greatly reduced. Fourth, operation and development become simple and low-cost because no packaging or fluid knowledge background is required.

The present application first provides a liquid circuit structure, comprising

The first wall,

The second wall surface is configured to be disposed close to or at least partially in contact with the first wall surface, and the space facing each other forms a flow basin, and the flow basin includes a thin flow basin;

The inlet structure is configured to include one or more inlets, which are in communication with the flow field when in operation, so that the fluid including at least the first fluid can be introduced into the flow field; the outlet structure is configured to include one or more outlets, which are in communication with the flow field when in operation, so that the fluid passing through the flow field can be discharged;

wherein the first fluid comprises a liquid;

Among them, when working:

The fluid at at least one inlet location of the inlet structure can be directly exposed to the environment outside the flow basin without passing through a pipeline; and/or

The fluid at at least one outlet position of the outlet structure can be directly exposed to the environment outside the flow basin without passing through a pipeline, and/or

The fluid at at least one location in the basin is directly exposed to the environment outside the basin;

The first fluid is configured to be able to be applied with energy during operation, and the energy can be converted into fluid kinetic energy, thereby forming a shear flow of the first fluid in the flow domain. The thin flow domain can be emptied or filled with fluid during operation.

Optionally, during operation, the first wall surface is configured to be able to move relative to the second wall surface, thereby applying energy to the first fluid and driving the shear flow of the first fluid.

Optionally, the relative movement of the first wall includes translation in a direction substantially parallel to the second wall, translation in a direction approaching or moving away from the second wall, and rotation relative to the second wall.

Optionally, the first wall surface rotating relative to the second wall surface includes the first wall surface rotating and the second wall surface being stationary.

Optionally, the first wall and the second wall comprise a disc shape, the first wall is substantially planar, the second wall is substantially planar, and the first wall is substantially parallel to the second wall;

During operation, the first wall surface is configured to rotate so as to apply energy to the first fluid and drive the first fluid to traverse the second wall surface.

Optionally, the first fluid is configured to be capable of shear flow when energy is applied thereto based on one of force, heat, light, and electrical effects.

Optionally, the inlet structure includes a first inlet and a second inlet;

In which, the first fluid flows into the flow basin from the first inlet and flows out from an outlet of the outlet structure, the second fluid flows into the flow basin from the second inlet and flows out from an outlet of the outlet structure, sharing an outlet with the first fluid, or flows out from another outlet of the outlet structure, using different outlets with the first fluid, wherein the second fluid and the first fluid are laminar flows in the thin flow basin, and the second fluid occupies a certain space in the thin flow basin so that the required amount of the first fluid is further reduced.

Optionally, the second fluid contacts the first fluid in a thin flow region, and its flow area does not overlap with the first fluid.

Optionally, the movement of the second fluid can drive the first fluid to perform shear flow.

Optionally, the fluid can be introduced in a temporally or spatially discrete manner through the inlet structure, wherein:

The inlet structure includes an inlet, and each first fluid is introduced into the inlet at different times, or when each first fluid is introduced into the inlet at the same time, an incompatible fluid is used to separate each first fluid, so that each first fluid will not mix with each other before entering the thin flow area; or

The inlet structure includes a plurality of inlets, and each first fluid is introduced through a different inlet, so that each first fluid will not mix with each other before entering the thin flow domain.

Optionally, the inlet structure further comprises a liquid storage structure for storing a predetermined amount of the first fluid to ensure that a sufficient amount of the first fluid fills the flow field through the inlet and prevents air from being brought into the flow field;

The predetermined amount is configured to be slightly larger than a required fluid capacity of the flow domain.

Optionally, the first wall and the second wall include curved surfaces to form a sleeve shape, wherein one of the first wall and the second wall forms an outer cylinder, and the other forms an inner cylinder, and a flow domain is formed between the two. During operation, at least one of the outer cylinder and the inner cylinder can move, and the movement includes: rotation or axial linear motion or axial linear motion while rotating.

Optionally, the first wall surface forms an outer cylinder, and the second wall surface forms an inner cylinder. The inner cylinder moves, and the outer cylinder is stationary. The movement includes: rotation and/or axial movement.

Optionally, the height of the inner cylinder is lower than that of the outer cylinder.

Optionally, both the inner cylinder and the outer cylinder comprise cylinders; or

The inner cylinder comprises a multi-faceted cylindrical cylinder, and the outer cylinder comprises a cylindrical cylinder; or

The outer cylinder comprises a multi-faceted cylindrical cylinder, and the inner cylinder comprises a cylindrical cylinder.

Optionally, the outlet structure is configured to enable the fluid from the thin flow area to be discharged freely and unobstructed to avoid blockage affecting the fluid introduction inlet.

Optionally, the materials of the first wall and the second wall are selected to have hydrophilicity and hydrophobicity such that the first fluid can be located between the first wall and the second wall in a free state without being expelled by surface tension, for example, the hydrophilic and hydrophobic material includes an HMDS coating.

Optionally, the material of the second wall is selected such that it has poor affinity with the first fluid in the flow domain, so that the first fluid flowing out of the flow domain by shear flow will be sucked back into the flow domain.

Optionally, the sum of cosine values of contact angles of the first wall and the second wall with the first fluid is greater than or equal to zero.

Optionally, the inlet comprises a free surface, or the fluid connected to the inlet has at least one free surface; the outlet comprises a free surface, or the fluid connected to the outlet has at least one free surface.

Optionally, the thick dimension of the thin flow domain is at least one order of magnitude smaller than the long and/or wide dimensions of the thin flow domain.

Optionally, the thin flow domain has a thickness of 2-100 microns.

Optionally, the first fluid between the first wall and the second wall has a velocity gradient, and the first fluid has a faster flow velocity on the side affected by energy or with less resistance.

Optionally, the liquid circuit structure further includes a heater;

The heater is configured to be capable of heat transfer with the first wall surface and/or the second wall surface for heating the flow area.

Optionally, the flow domain includes a plurality of temperature zones, and the plurality of temperature zones are separated by at least one insulation block disposed on the second wall surface, respectively, wherein the temperatures of the plurality of temperature zones are the same or different.

Optionally, the first wall and the second wall include a disc shape, and the second wall is configured to rotate during operation, thereby applying energy to the first fluid to drive the shear flow of the first fluid.

Optionally, the first wall surface is configured to be stationary, or to rotate, or to perform linear motion in a direction substantially parallel to the second wall surface, or to rotate and perform linear motion in a direction substantially parallel to the second wall surface.

Optionally, the inlet structure comprises a channel provided at a predetermined position of the first wall surface and/or the second wall surface for introducing the fluid into the flow domain.

Optionally, the channel comprises a through hole arranged on the first wall surface and/or the second wall surface at a position close to the center of the disk.

Optionally, the channel includes a liquid inlet pipe attached to the first wall and/or the second wall, so that the first fluid is sucked into the flow field.

Optionally, the outlet structure includes an area between the disc periphery of the first wall and the disc periphery of the second wall, enabling the first fluid to be discharged through the area.

Optionally, the liquid path structure is a microfluidic liquid path structure.

A second aspect of the present application provides a device comprising the fluid path structure according to the present application.

The third aspect of the present application provides an operating method of a liquid circuit structure, comprising:

providing a first wall surface,

Providing a second wall surface, which is configured to be disposed close to or at least partially in contact with the first wall surface, and the space facing the second wall surface forms a flow domain, and the flow domain includes a thin flow domain;

Providing an inlet structure configured to include one or more inlets in operative communication with the flow basin so that a fluid including at least a first fluid can be introduced into the flow basin;

Providing an outlet structure, which is configured to include one or more outlets and is in communication with the flow basin during operation so that the fluid passing through the flow basin is discharged;

wherein the first fluid comprises a liquid;

Among them, when working:

The fluid at at least one inlet location of the inlet structure can be directly exposed to the environment outside the flow basin without passing through a pipeline; and/or

The fluid at at least one outlet position of the outlet structure can be directly exposed to the environment outside the flow basin without passing through a pipeline, and/or

The fluid at at least one location in the basin is directly exposed to the environment outside the basin;

The first fluid is configured to be able to be applied with energy, and the energy can be converted into fluid kinetic energy, thereby forming a shear flow of the first fluid in the flow domain, and the thin flow domain can be emptied or filled with fluid during operation.

Optionally, during operation, the first wall surface is configured to be able to move relative to the second wall surface, thereby applying energy to the first fluid and driving the shear flow of the first fluid.

Optionally, the relative movement of the first wall includes translation in a direction substantially parallel to the second wall, translation in a direction approaching or moving away from the second wall, and rotation relative to the second wall.

Optionally, the first wall surface rotating relative to the second wall surface includes the first wall surface rotating and the second wall surface being stationary.

Optionally, the first wall and the second wall comprise a disc shape, the first wall is substantially planar, the second wall is substantially planar, and the first wall is substantially parallel to the second wall;

During operation, the first wall surface is configured to rotate so as to apply energy to the first fluid and drive the first fluid to traverse the second wall surface.

Optionally, the first fluid is configured to be capable of shear flow when energy is applied thereto based on one of force, heat, light, and electrical effects.

Optionally, the inlet structure comprises a first inlet and a second inlet,

wherein the first fluid flows from the first inlet through the flow field and flows out from an outlet of the outlet structure,

The second fluid flows into the flow field from the second inlet and flows out from an outlet of the outlet structure, and the first fluid and the second fluid share one outlet, or flows out from another outlet of the outlet structure, and the first fluid and the second fluid use different outlets respectively.

The second fluid and the first fluid are laminar flows in the thin flow area, and the second fluid occupies a certain space in the thin flow area so that the required amount of the first fluid is further reduced.

Optionally, the second fluid contacts the first fluid in a thin flow region, and its flow area does not overlap with the first fluid.

Optionally, the movement of the second fluid can drive the first fluid to perform shearing movement.

Optionally, the fluid is introduced in a temporally or spatially discrete manner through an inlet structure, wherein:

The inlet structure includes an inlet, and each first fluid is introduced into the inlet at different times, or when each first fluid is introduced into the inlet at the same time, an incompatible fluid is used to separate each first fluid, so that each first fluid will not mix with each other before entering the thin flow area; or

The inlet structure includes a plurality of inlets, and each first fluid is introduced through a different inlet, so that each first fluid will not mix with each other before entering the thin flow domain.

Optionally, the inlet structure further includes a liquid storage structure for storing a predetermined amount of the first fluid to ensure that a sufficient amount of the first fluid fills the flow basin through the inlet and prevents air from being brought in; wherein the predetermined amount is slightly larger than the fluid capacity required by the flow basin.

Optionally, the first wall and the second wall include curved surfaces to form a sleeve shape, wherein one of the first wall and the second wall forms an outer cylinder, and the other forms an inner cylinder, and a flow domain is formed between the two. During operation, at least one of the outer cylinder and the inner cylinder can move, and the movement includes: rotation or axial linear motion or axial linear motion while rotating.

Optionally, the first wall surface forms an outer cylinder, and the second wall surface forms an inner cylinder. The inner cylinder moves, and the outer cylinder is stationary. The movement includes: rotation and/or axial movement.

Optionally, the inner cylinder is configured to be lower in height than the outer cylinder.

Optionally, both the inner cylinder and the outer cylinder comprise cylinders, or

The inner tube comprises a multi-faceted cylinder and the outer tube comprises a cylinder, or

The outer cylinder comprises a multi-faceted cylindrical cylinder and the inner cylinder comprises a cylindrical cylinder.

Optionally, the inner cylinder comprises a multifaceted cylindrical cylinder and the outer cylinder comprises a cylindrical cylinder, further comprising the steps of:

S1. A chip is arranged on the cylindrical surface of a multi-faceted cylinder, the chip faces the outer cylinder and is located in the flow field between the inner cylinder and the outer cylinder;

S2. Providing a first first fluid through the inlet until the inner cylinder and the outer cylinder are filled with the first first fluid, wherein the first first fluid is a liquid, preferably, comprising pure water, or IPA, or Acetone;

S3. The outer cylinder starts to rotate and axially reciprocate, while the first fluid is continuously added, and the first fluid continuously flows out from the outlet.

S4. As the outer cylinder moves, the first first fluid moves, and the first first fluid approaches laminar flow where the inner wall of the inner cylinder and the outer cylinder are close to each other;

S5. Provide a second first fluid into the flow field through the inlet to clean the inner cylinder surface chip; the second first fluid includes a high-pressure gas and/or a surfactant;

S6. Lower the inner cylinder to expose the chip surface and dry the surface with high-pressure air.

S7. Take out the chip,

This completes the cleaning of the chip.

Optionally, the outlet structure is configured to enable the fluid from the thin flow area to be discharged freely and unobstructed to avoid blockage affecting the fluid introduction inlet.

Optionally, the materials of the first wall and the second wall are selected to have hydrophilicity and hydrophobicity such that the first fluid can be located between the first wall and the second wall in a free state without being expelled by surface tension, for example, the hydrophilic and hydrophobic material includes an HMDS coating.

Optionally, the material of the second wall is selected such that it has poor affinity with the first fluid in the flow domain, so that the first fluid flowing out of the flow domain by shear flow will be sucked back into the flow domain.

Optionally, the sum of cosine values of contact angles of the first wall and the second wall with the first fluid is greater than or equal to zero.

Optionally, the inlet comprises a free surface, or the fluid connected to the inlet has at least one free surface; the outlet comprises a free surface, or the fluid connected to the outlet has at least one free surface.

Optionally, the thick dimension of the thin flow domain is at least one order of magnitude smaller than the long and/or wide dimensions of the thin flow domain.

Optionally, the thin flow domain has a thickness of 2-100 microns.

Optionally, there is a velocity gradient for the first fluid between the first wall and the second wall, and the first fluid has a faster flow velocity on the side affected by energy or with less resistance.

Optionally, the liquid path structure further includes a heater, and the heater is configured to perform heat transfer with the first wall surface and/or the second wall surface to heat the flow area.

Optionally, the flow domain includes a plurality of temperature zones, and the plurality of temperature zones are separated by at least one insulation block disposed on the second wall surface, respectively, wherein the temperatures of the plurality of temperature zones are the same or different.

Optionally, the first wall and the second wall comprise a disc shape, the first wall is substantially planar, the second wall is substantially planar, and the first wall is substantially parallel to the second wall;

During operation, the second wall surface is configured to be able to rotate relative to the first wall surface, thereby applying energy to the first fluid and driving the shear flow of the first fluid.

Optionally, the first wall surface is configured to be stationary, or to rotate, or to perform linear motion in a direction substantially parallel to the second wall surface, or to rotate and perform linear motion in a direction substantially parallel to the second wall surface.

Optionally, the second wall includes a chip, the second wall is configured to have hydrophilic regions and hydrophobic regions that are alternately arranged, wherein biomolecules are fixed on the hydrophilic regions, the biomolecules include single-stranded DNA, and the hydrophobic regions are covered with hydrophobic substances, and the area of the first wall is greater than or equal to the area of the second wall; the operation method further includes:

S1. Providing a first first fluid through an inlet structure, the first first fluid comprising a reagent capable of disconnecting an azide group, so that a first reaction between the first first fluid and a biomolecule occurs;

S2. Providing a second first fluid through an inlet structure, the second first fluid comprising a buffer reagent for cleaning the first first fluid and the product of the first reaction;

S3. Providing a third first fluid through the inlet structure, the third first fluid comprising a synthetic reagent containing four bases ACTG and corresponding dye groups, so as to cause a second reaction between the third first fluid and the biomolecule;

S4. Providing a fourth first fluid through the inlet structure, the fourth first fluid comprising a buffer reagent for cleaning the third first fluid, wherein the fourth first fluid and the second first fluid are the same or different components of the buffer reagent;

S5. Recording and determining the base type of the product of the third reaction on the chip by sensing;

Repeat steps S1-S5 multiple times to obtain the base sequence of the DNA single strand based on the base types of the product of the third reaction.

Optionally, the following steps are further included between step S4 and step S5:

S4.1. Providing a fifth first fluid through the inlet structure, the fifth first fluid comprises a synthetic reagent containing four base groups of ACTG and corresponding dye groups, so that a third reaction of the fifth first fluid with the biomolecule occurs;

S4.2. Provide a sixth first fluid through the inlet structure, wherein the sixth first fluid includes a buffer reagent for cleaning the fifth first fluid, wherein the sixth first fluid and the second first fluid and the fourth first fluid are buffer reagents of the same or different components.

Optionally, the operating method further includes: immediately before step S5, the step of providing a seventh first fluid through the inlet structure, wherein the seventh first fluid includes a protective reagent to prevent the recording process from causing adverse effects on the DNA.

Optionally, the first fluid comprises a triphenylphosphine solution.

Optionally, step S5 includes: recording by sensing means including: taking photos to record the fluorescence on the chip, and determining the type of base by a basecall algorithm.

Optionally, the outlet structure includes an area between the periphery of the disk on the first wall and the periphery of the disk on the second wall, enabling the first fluid to be discharged through the area, and the operating method further includes:

A waste liquid collection structure is provided for collecting the discharged first fluid.

Optionally, in step S2, the reaction time of the first reaction is 1 minute.

Optionally, in step S2, the volume of the second first fluid is three times the volume of the flow basin.

Optionally, in step S3, the volume of the third first fluid is 1.5 times the volume of the flow basin.

Optionally, in step S3, the second reaction is carried out at a temperature of 55° C., and the reaction time of the second reaction is 1 minute.

Optionally, the inlet structure comprises a channel arranged at a predetermined position of the first wall surface and/or the second wall surface, for introducing the fluid into the flow domain.

Optionally, the channel comprises a through hole arranged on the first wall and/or the second wall at a position close to the center of the disk.

Optionally, the channel includes a liquid inlet pipe attached to the first wall and/or the second wall, so that the first fluid is sucked into the flow field.

Optionally, the outlet structure includes an area between the disc periphery of the first wall and the disc periphery of the second wall, enabling the first fluid to be discharged through the area.

A fourth aspect of the present application provides an operating method of a microfluidic circuit structure, comprising:

Providing a pipeline, the pipeline comprising an inlet structure and an outlet structure, the inlet structure comprising at least one inlet, and the outlet structure comprising at least one outlet;

During operation, a first fluid and a second fluid incompatible with the first fluid are introduced into the pipeline through different inlets of at least one inlet, wherein the first fluid and the second fluid are discharged through at least one outlet to form a flow domain between the inlet structure and the outlet structure; wherein the second fluid occupies a certain volume of the flow domain to form a thin flow domain of the first fluid.

Optionally, the second fluid flows in the pipeline, driving the first fluid to shear flow in the pipeline.

Optionally, the second fluid is configured not to undergo macroscopic flow.

Optionally, the thin flow domain has a thickness of at least 2 microns.

Optionally, the inlet structure comprises a solenoid valve configured to control the introduction of the first fluid and the second fluid into the pipeline.

The liquid path structure provided in the present application mainly utilizes the shear force of the fluid to construct a Couette-like flow field, so as to replace the Poisson leaf flow field constructed by pure pressure drive in the prior art.

The device provided by the present application is beneficial to the overall quality control in the case of a significant reduction in the number of fluid path structural components. In addition, since the fluid path structure does not need to be packaged, the operator of the device does not need to have fluid knowledge background, which can reduce costs while facilitating operation and development.

The Couette-like flow field construction method provided in the present application injects the fluid into the inlet and starts the shear force driving device, so that the fluid is injected into at least a thin flow domain within the flow domain, so that the interaction can occur. In the present application, since the pressure drive or surface tension drive of the traditional microfluidic platform is replaced by shear force drive, on the one hand, the improvement of energy input and performance optimization are more convenient, and there is no problem of pressure overlimit; in addition, the structure is simple, avoiding the learning and use obstacles caused by a large number of external equipment; thirdly, a large number of external pipelines are eliminated, saving cleaning time and cost. Fourth, sealing is not required, avoiding the cost and inconsistency of packaging.

Therefore, this application overcomes the problems of high cost, difficulty in using, and low performance of traditional microfluidic devices, making its market penetration prospect more prominent.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

Figure 1 is a schematic diagram comparing the structural principles of a Couette flow device in the present invention and a Poiseuille flow device in the prior art, wherein Figure 1(a) and Figure 1(b) respectively show a typical implementation form of the device of the present invention and two ways of generating shear force, and Figure 1(c) shows a Poiseuille flow device in the prior art, a typical structural cross-section of a flow cell, and schematic diagrams of different models of actual objects.

Figure 2 is a comparative simulation of a traditional microfluidic device flow cell and a Shear-driven microfluidics device using fluid simulation software, wherein Figure 2(a) shows the effect of flow rate on the pressure difference between the inlet and outlet of the patented method and the traditional flow cell method when other parameters are constant; Figure 2(b) shows the effect of wall gap on the pressure difference when other parameters are constant; Figure 2(c) shows the effect of wall length on the pressure difference when other parameters are constant, wherein the wall gap is 20 microns, the chip length is 7 cm, and the average flow rate is 0.16 m/s.

Figure 3 is a schematic diagram of the reagent replacement speed and reagent consumption of a traditional microfluidic device flow cell and a Couette-like flow device simulated using fluid simulation software, wherein Figure 3(a) shows a 3D graph of the concentration change of the reagent replaced from 0.16 m/s to the average speed of the Couette-like flow device, Figure 3(b) shows a side view of the concentration change, Figure 3(c) shows the effect on the replacement ratio when the flow rate is used as a variable and other constants compared with the flow cell, where the replacement ratio is defined as the ratio of the required reagent volume to the chamber volume, and Figure 3(d) shows the effect of the pipe/chamber volume ratio as a variable on the amount of dNTP used in each nanopore.

FIG. 4 is a schematic diagram of a device for applying a Couette-like flow to two planes approaching each other and moving relative to each other to save the amount of fluid consumed in the process.

FIG. 5 is a schematic diagram of a device for applying a Couette-like flow to two mutually adjacent planes to save the amount of fluid consumed in a gene sequencing process according to the embodiment of FIG. 4 .

FIG6 is a schematic diagram of a device that applies a Couette-like flow to two surfaces that are close to each other and move relative to each other to save the amount of reagents consumed in the process. FIG6(a) shows a schematic diagram of the device in this embodiment, FIG6(b) shows a schematic diagram of the working principle of this embodiment, and FIG6(c) shows an instrument schematic diagram of the Roche Cobas Liat microfluidic system in the prior art.

FIG. 7 is a schematic diagram showing the change of fluorescence intensity during the DNA amplification cycle according to the process of the embodiment of FIG. 6 .

Fig. 8 is a schematic diagram of a device for actively moving a wall surface of a Couette-like flow, which is a moving liquid that flows in layers with the liquid to be saved. Fig. 8(a) shows a real photo and an enlarged microscopic photo of a flow pool of a conventional process, Fig. 8(b) shows a 3D diagram (showing the layered flow interface between the two fluids) of a flow process in two directions including a flow velocity slice (showing the distribution of the flow velocity, indicating that the liquid to be saved is a shear flow); Fig. 8(c) shows another equivalent design of the flow field;.

Figure 9(a) shows an inlet design of a flow field according to the embodiment of Figure 8, and Figure 9(b) shows a system according to the embodiment of Figure 8, which shows a device that utilizes a macroscopically static liquid that is layered and in contact with the liquid to be saved.

Figure 10 is a schematic diagram of a device in which the type of stationary wall (second wall) of the Couette-like flow is selected to have very low affinity for the fluid between the two walls, and when the first wall moves, the fluid flowing out of the flow area will retract and always follow the movement of the wall.

FIG. 11 is a top view of another structure of the device according to the embodiment of FIG. 10 , wherein the fluid can move to one or several areas in the checkerboard structure.

12 is a schematic diagram of a device in which the wall type of active movement of Couette-like flow is selected as a strip of unwinding and winding, and the liquid inlet is kept filled so that the fluid can be directly added.

FIG. 13( a ) and FIG. 13( b ) show two implementations of bypass arrangement when the liquid inlet of the liquid path structure remains filled with excess fluid.

Figure 14(a) is a schematic diagram of a sampling method device through time discretization in the present embodiment, Figure 14(b) is a schematic diagram of a sampling method device through space discretization in the present embodiment, Figure 14(c) is a schematic diagram of a sampling method device through time and space discretization in the present embodiment, and Figure 14(d) is a schematic diagram of a sampling method device through changing the shape of one of the walls to keep the inlet full in the present embodiment.

Figure 15(a) is a schematic diagram of another sampling method device through time discreteness in the embodiment of Figure 14(a), Figure 15(b) is a schematic diagram of another sampling method device through space discreteness in the embodiment of Figure 14(b), and Figure 15(c) is a schematic diagram of another sampling method device through time and space discreteness in the embodiment of Figure 14(c).

16 is a schematic diagram of a side view and a top view of a device for maintaining a Couette-like flow in a flow domain by providing a retaining force through a hydrophobic substance at a curved liquid surface or an edge, without adding side walls on both sides of the flow direction.

Figures 17(a), 17(b), 17(c) and 17(d) are schematic diagrams of four types of devices in which the first wall and the second wall do not move, but there is a mechanism between the walls to push the liquid to form shear flow.

FIG. 18 is a schematic diagram of a device for selecting the direction of wall motion of the active motion of a Couette-like flow as up and down motion.

FIG. 19 is a schematic diagram of applying a Couette-like flow to a nucleic acid assay system according to the embodiment of FIG. 18 .

Figure 20 is a schematic diagram of an apparatus that applies Couette-like flow to two surfaces that are close to each other and move relative to each other, one selected flat surface and the other selected curved surface, to save the amount of reagents consumed in the process.

FIG. 21 is a schematic diagram of a device in which the second wall surface is set to be stationary and the first wall surface is set to rotate.

FIG. 22 is a schematic diagram of various possible forms of a thin watershed.

FIG. 23 is a flow chart for constructing a Couette-like flow field microfluidic device.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

In the description of this application, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying the function, relative importance or implicitly indicating the number of the indicated technical features.

It should be noted that when a component is referred to as being "fixed to" or "mounted on" another component, it may be directly on the other component or there may be a central component. When a component is considered to be "set on" another component, it may be directly set on the other component or there may be a central component at the same time. The term "and/or" as used herein includes all and any combinations of one or more of the relevant listed items.

In order to help better understand the solution provided by the embodiment of the present disclosure, before introducing the method provided by the embodiment of the present disclosure, the Couette-like flow field in the aforementioned embodiment and the device constructed therefrom are further explained as follows:

Couette flow is a typical shear-driven flow field in fluid mechanics. It describes the flow between two parallel walls of infinite length and width, where one wall is fixed and the other moves at a constant speed, thus forming a stable shear force. Therefore, the construction device of this type of Couette flow field should have the following elements:

1. Parallel walls: Couette flow occurs between two parallel walls, which can be flat plates, cylinders or other parallel geometric shapes.

2. Relative motion: One of the two walls remains stationary while the other moves at a constant speed. This relative motion triggers the flow of the fluid.

3. No pressure gradient: In an ideal Couette flow field, there is no pressure gradient along the flow direction (i.e. the direction parallel to the moving wall). This means that the pressure can only change in the direction perpendicular to the flow direction.

4. Viscous fluid: Couette flow usually involves viscous fluids, where viscosity plays a key role. The viscosity of the fluid leads to velocity gradients between fluid layers, creating shear forces.

5. Shear flow: Due to the movement of one wall and the stationary of the other wall, the velocity of the fluid decreases as the distance from the moving wall increases. The flow caused by this velocity gradient is called shear flow.

6. Steady-state flow: Under constant conditions, Couette flow eventually reaches a steady state, that is, the flow state of the fluid no longer changes with time.

The ideal Couette flow field is composed of two parallel walls of infinite length or width, and the pressure-free fluid fills the space between the walls from the beginning. However, the volume of the equipment in practical applications is limited, and certain technical means are required to introduce the fluid into the flow field without affecting the flow field characteristics to the greatest extent.

In this regard, the present application provides a fluid device, the technical concept of which is:

First of all, parallel walls are a major factor. In order to simulate infinite walls in a limited area, the inventors mainly considered the following three key points:

The first point is that the sidewalls perpendicular to the flow direction restrict the fluid from overflowing or can control the overflow without affecting the flow field;

The second point is to ensure that the supply volume is not less than or slightly exceeds the volume flowing through the basin in the import and export directions, and that the passage is unobstructed;

The third point is that the walls need to be close enough to each other (the scales involved in microfluidics are usually in the micrometer range) to work well, ensuring that the walls can still be parallel at such a small distance.

Among them, regarding the first key point, the inventor believes that there are at least the following practical operation methods:

1. Within the range where two walls are opposite to each other, the inventor designs the wall surface or various related properties thereof to match the flowing fluid, such as a hydrophilic wall and an aqueous fluid, or a hydrophobic substance and an oily fluid, which can confine the liquid between the two adjacent walls.

2. Design obstacles around the flow area that are difficult for the liquid to cross. For example, when the fluid is an aqueous fluid, design a hydrophobic area on the wall, and the liquid will need a lot of energy to flow through.

The result of both schemes is that the fluid at the boundary is in direct contact with the air, thus forming a slip interface, which theoretically can achieve the same effect as a wall of infinite width, thereby realizing the same characteristics as Couette flow.

3. The width of one wall (perpendicular to the flow direction) is larger than that of the other wall, so that the liquid between the walls can be constrained by the principle of pinning wire and will not exceed the narrow wall significantly. In this case, the flow at the edge is more complicated, but the overflowing fluid can eventually be carried away by the shear force, as shown in Figure 13.

4. Design a wall, such as a half wall or a liquid wall, as shown in Figure 8 or 9, to form a physical constraint, so that the velocity of the fluid contacting the wall is 0 or slower than the fluid inside, and even overflow and capillary phenomena may occur. However, if the flow domain area is large enough or the overflow is controllable, the fluid inside the thin film area can still be less affected, and the overall behavior is close to that of Couette flow.

Regarding the second key point, in order to prevent other unnecessary fluids, such as air, from being sucked in, there needs to be sufficient fluid at the inlet. In addition, the Couette field is a zero-pressure field, and the flux inside is equal to the cross-sectional area multiplied by the average velocity. Due to the deviation between reality and the ideal situation, there may be pressure, and sometimes it may fluctuate. Due to the narrow gap, it is difficult to actually measure. Therefore, the way to ensure safety is that there is always excess liquid at the inlet; in terms of operating methods, the amount of liquid should exceed the amount required by the system, and the excess liquid can be discharged from the system through the bypass, as shown in Figure 13.

There are many ways to allow fluid to enter the thin flow field at the inlet. The preferred solution proposed in the present disclosure is discrete. The specific implementation methods include:

1. Use a pipette to drip liquid into the perforations at the bottom of the chip. The discrete droplets are wrapped in air and directly enter the thin flow field. The advantage of this is that there is no common passage that needs to be cleaned and through which various reagents need to pass. Traditional pressure-driven microfluidics must seal and pressurize the equipment with pipes, which cannot achieve this.

2. Different reagents enter the thin basin separately through physical isolation, and different reagents are also discrete in space. After entering the basin, laminar flow and shear drive are still the main driving force, which can achieve better cleaning.

In the embodiments of the present application, physical isolation between different reagents can be achieved by air or an inert reagent incompatible with other reagents, or by different pipeline structures and multiple different inlets, as shown in FIG. 14 .

3. Allow the reagent to enter the thin flow area in the form of steam and solidify into liquid, or use gas to push the liquid into the thin flow area.

4. The liquid first enters a liquid storage structure, such as a liquid storage pool formed on a single wall or multiple walls close to each other, which is also part of the flow basin, and finally enters the thin flow basin.

5. The liquid first adheres to a certain wall surface, and then enters the thin flow area by the relative movement between the walls. For example, a lifting platform controls two walls to approach each other, and liquid is pre-attached to one of the walls. There are many different printing schemes that can be used to attach liquids, such as lamination, transfer, coating (or spraying, printing), mutual exclusion, coating, inkjet, etc. In short, in order to avoid cross-contamination of liquids, either the common channel is removed, or the common channel can be emptied with the assistance of gas/air pressure. The final effect is to prevent the liquids from mixing with each other before entering the flow area, or the amount of mixing is extremely low compared to the pressure-driven method through the pipeline.

The second key point is that at the outlet, the flow should be kept smooth and the pressure should be stable (for example, stable at 0), otherwise the liquid at the inlet may not flow through the thin flow basin but directly flow to the surrounding bypass. The key point here is mainly the diversion effect at the outlet, which can be achieved in the following ways:

1. The outlet has a shape that allows fluid to escape easily, such as a slope, a pointed mouth, a comb-like structure, or one side is longer than the other;

2. There are some ways to remove the accumulated liquid at the outlet, such as contact with fiber-containing water-absorbing materials or air blowing, and the waste liquid is collected by negative pressure;

3. Set up a certain flow channel at the outlet to reduce the resistance of the fluid leaving the system;

4. There is no physical obstruction at the outlet, and one sliding wall is longer than the other walls, so the liquid leaves the flow area directly following the shear force of the sliding wall;

5. Contact with other fluids such as air and use gravity to separate;

6. Pressure-assisted release.

Regarding the third key point, Couette flow requires parallel walls, which may not be achieved in reality, especially at a microscopic scale. There are the following ways:

1. Achieve roughly parallelism, and a certain inclination is also acceptable. In this case, partial reflux may occur, but the purpose of the fluid channel is also achieved;

2. Let the two walls contact directly, and the actual flow channel thickness is determined by the roughness. Because only the highest points have atomic-level contact at the microscopic level, and the fluid will flow through its microscopic gaps, regardless of whether the rough structure is artificial or natural;

3. Precise control, such as lifting platform or mechanical locking;

4. Use an object of a certain thickness as a gasket so that there is a gasket height between the walls without gaskets. The disadvantage is that part of the gasket area will be lost. Generally speaking, in order for the shear force to play a major role, the walls need to be close enough to each other;

Through the above three key points, the simulation of the flow domain within a limited area can be basically achieved.

After the simulated flow domain is realized, how to generate shear force is also a major factor. See Figure 23. In order to generate shear force by moving part of the liquid in the flow domain, the following three methods of generating shear force are mainly considered:

1. The simplest one is that the walls that make up the flow basin move relative to each other;

2. The wall can be a solid wall or a liquid wall;

3. The wall does not physically move, but the liquid close to the wall moves through some force, heat, light, electricity or magnetism.

Among them, regarding the first method of generating shear force, the inventor believes that there are at least the following practical operation methods:

1. The wall moves relative to the wall in a direction parallel to the wall. Due to the non-slip boundary condition, the fluid layer in contact with the wall moves at a constant speed. Different walls have different speeds, which generates a velocity gradient in the direction between the flow domains. For thin flow domains, a velocity gradient is generated in the height direction. Then, each particle in the viscous fluid in the height direction will be affected by this velocity gradient and start to move.

2. The relative movement of the wall is in the vertical direction or the rotational direction. At this time, in order to ensure the single direction of the liquid, auxiliary devices such as valves or gravity are required, but its essence is still to obtain shear force through the moving wall and finally convert it into the power of fluid flow, as shown in Figure 1(b).

3. The relative movement of the wall is in the form of rotation with a certain point or line as the center. At this time, the direction of the shear force is consistent with the direction of rotation, and a centripetal force is also obtained. The difference between it and the existing microfluidic turntable is that the traditional turntable rotates with the upper and lower plastics together, with only centripetal force but no shear force, and the liquid flows from the center to the outside;

The traditional method uses various structures to form resistance. Since there is no surface tension of the valve without air, air is a necessary component.

In the embodiment of the present application, one wall is configured to move, and the other wall may be stationary, with a shear force above and below, which forms the power of fluid movement, and the liquid can flow in a direction perpendicular to the diameter, as shown in Figure 6. Even if the two walls move at the same time, there is no air in the flow domain during the reaction.

Among them, regarding the second method of generating shear force, the inventor believes that there are at least the following practical operation methods:

1. Use magnetic field and magnetic fluid to form the tube wall, and the liquid flows in the tube formed in the middle of the magnetic fluid. When the wall of the magnetic fluid moves due to the movement of the magnetic field, the liquid in contact with it also flows due to the shear force;

2. In a thin flow domain, two or more immiscible and easily separable liquids are filled. During laminar flow, the two liquids may be stratified in various situations. Among them, the effective fluid at least partially contacts other auxiliary liquids that are immiscible with it. At this time, the auxiliary liquid becomes the liquid wall of the effective fluid. When the liquid wall flows, the effective liquid is also affected by the shear force and begins to flow at the same time, and the energy required is also lower.

Among them, regarding the third method of generating shear force, the inventor believes that there are at least the following practical operation methods:

1. In electrowetting, the surface tension of the interface is the Helmholtz free energy required to create a certain area of the surface. It includes two parts: chemical and electrical. By changing the electric field, the properties of the liquid itself or the hydrophilicity of the wall can be changed, and the liquid close to the wall moves and forms a velocity gradient with the liquid away from the wall.

2. Through light-induced liquid deformation, part of the liquid begins to flow, and through shear force and continuous liquid feeding, the entire system flows;

3. By controlling the movement of the magnetic fluid, other liquids in contact with the magnetic fluid in the flow area flow;

4. Through vibration (e.g., Rayleigh waves) or resonance, some liquids gain energy and begin to flow, thereby affecting the flow of other liquids.

5. Use hot bubbles to make part of the liquid move first, thereby affecting the flow of other liquids.

In short, energy is obtained within the system and shear force is generated, and then by continuous liquid supply, a relatively stable shear flow is generated in the thin flow area, thereby achieving rapid surface cleaning and liquid replacement.

After the shear force is generated, zero pressure is also a major factor considered in this application. The zero pressure gradient in the definition of the Couette flow field is an ideal situation. In reality, pressure is almost inevitable. In order to achieve a pressure drive that is several orders of magnitude smaller than the traditional microfluid pressure-driven Poisson flow, the inventors mainly made the following considerations: the inlet or outlet of the traditional pressure-driven microfluidic device is directly connected to the pump, and the inlet and outlet have a considerable pressure difference. The pressure energy of the fluid is provided by the pump, which offsets the friction of the liquid in the microchannel and is eventually converted into heat energy. The low-pressure injection pump pressure is about 50kPa. The fluid device of this application is mainly affected by the velocity gradient generated by the shear force driving the liquid on the upper and lower sides of the thin flow basin, and the shear force has nothing to do with the pump. Even if a pump is involved, it is for the purpose of more convenient automated liquid feeding. The pressure difference between the outlet and the outlet of the flow basin is less than 20kpa or may even be 0, and at least half of the energy is provided by the shear force.

Specifically, the inlet or outlet of a conventional pressure-driven microfluidic device is directly connected to a pump, the device is closed as a whole, a small inlet for inlet and a small outlet for outlet, a thin sheet flow in the middle, and requires a large pressure difference to drive. In the microfluidic device of the present application, the liquid is driven by shear force, and at least one of the inlet, outlet or flow field is open to the environment, requiring a smaller pressure.

Finally, regarding the viscous fluid element, the inventors have mainly considered the following: the greater the viscosity, the stronger the ability to resist external shear force. If the viscosity of the fluid needs to be adjusted, it can be done by mixing substances with different viscosities that are inert to the current purpose. One solution is to add glycerol to water to increase the viscosity.

In summary, the present invention creates a thin flow basin, as shown in Figure 18, which is a possible shape of the thin flow basin; by combining at least one of the key points mentioned above, a part of the liquid in the flow basin can be continuously moved due to the shear force, and other liquids are also driven to move together due to viscosity, thereby forming a continuous flow in the thin flow basin without the need for external pressure, forming a Couette-like flow field. As shown in the design mind map of this patent in Figure 23, this type of platform that realizes the flow field is called a shear-driven open microfluidic platform. It is different from the Poisson leaf flow of the traditional pressure-driven microfluidic platform. The thin flow basin here is not necessarily a regular wall surface, but can also be various curved surfaces as shown in Figure 22. As long as the key points listed above are met, a Couette-like flow field can be formed.

Please refer to FIG. 1( a ), which is a schematic diagram of a typical Couette-like flow field constructed by the shear-driven fluid platform of the present invention. The first fluid 6 is directly added into the flow field 3 through the inlet 4, and then driven by the relative movement between the first wall 1 and the second wall 2, passes through the gap between the two, and leaves the flow field 3 from the outlet 5, wherein the side wall of the flow field 3 is open, but due to the constraint of surface tension, the first fluid 6 will not overflow.

It should be noted that, when there is no relative movement between the first wall 1 and the second wall 2 , after the first fluid 6 is added to the flow basin 3 through the inlet 4 , the first fluid 6 can pass through the flow basin 3 by gravity or other effects after the flow basin 3 is filled.

In the flow field 3, the first fluid 6 forms a shear flow, see Couette flow. Furthermore, the first fluid 6 in a device can be a gas or a liquid, or multiple liquids or multiple gases. By utilizing the relative movement of the gaseous first fluid 6 and/or the first wall 1 and the second wall 2, the original liquid in the flow field 3 can be drained. By utilizing the relative movement of the liquid first fluid 6 and/or the first wall and the second wall, in combination with a full inlet and an unobstructed outlet, the flow field can be filled with new liquid to quickly replace the original liquid. In short, by controlling the type of the first fluid, the speed and mode of relative movement between the first wall and the second wall, and the gap, it is possible to:

1. Drain the original liquid in the basin;

2. Renew and/or replace the original liquid in the basin with another liquid;

3. Fill the gas-filled flow area with a first fluid 6.

4. Use another fluid to squeeze out the original fluid in the flow basin.

5. Use surface tension to draw in fluid outside the flow area.

Unless otherwise specified, generally, the wall surface with the chip structure is used as the second wall surface, and the other wall surface is used as the first wall surface.

Through the above operations, the ultimate goal is to quickly operate the fluid and save costs. The reason why these strategies can achieve the above goals is that, first of all, the pressure of the traditional solution acts on the cross section of the microfluidic channel. Because the cross-sectional area is usually very small, for example, the length and width are both tens of microns, then the pressure must be relatively large to provide sufficient energy. This poses a greater challenge to seals such as valves and seals, and performance improvement is relatively difficult. When the new solution uses shear force to drive, the entire flow area can exert an influence on the fluid, which is usually a macroscopic area, and the required pressure often drops by an order of magnitude. In particular, when we prefer a thin sheet flow area instead of a traditional microchannel, so that only one dimension is microscopic, the driving area may increase by two orders of magnitude, and the required pressure may drop by more than one order of magnitude. As shown in the simulation of Figure 2, the microfluidic chip flow cell used for gene sequencing is compared with the solution of the present invention. At the same gap and flow rate, the pressure is three orders of magnitude greater. Therefore, we can use a lower gap, thereby greatly reducing the amount of reagents, cleaning fluids or precious samples used. A faster speed can also be used. In addition, because only one dimension is microscopic, it is easier to manufacture.

Specifically, Figures 2(a), 2(b) and 2(c) respectively show the relationship between flow velocity-pressure, gap size-pressure and length-pressure within the flow area of the flow cell and the technical solution of the present application.

In particular, when the shear motion is not sufficient to discharge the fluid between the two walls (for example, the shear speed is slow or the fluid has poor affinity with the larger surface), a "pinning line" phenomenon will be formed, that is, the liquid discharged from the flow field by shear is sucked back into the flow field. In this case, the fluid between the two walls moves with one of the moving walls, and there is no fluid remaining on the other wall. Another situation is that the outlet is not smooth. In this case, the imported liquid will be directly bypassed, and most of the liquid between the two walls will be retained. In these two cases, although the flow field is still in a state of shear flow, the effect is that "the fluid between the first wall 1 and the second wall 2 always follows the wall with strong affinity." Therefore, this function can be used when you do not want it to perform fluid replacement work. The equipment or use methods formed by these different phenomena of Couette-like flow fields will be introduced in the following embodiments and descriptions.

Therefore, in an optional embodiment, by controlling the type of the first fluid, the speed, mode and gap of the relative movement between the first wall and the second wall can also:

6. Allow the fluid between the first wall 1 and the second wall 2 to continue to follow a certain wall.

When using the function of "renewing and/or replacing the original liquid in the flow field with another liquid", due to the lower gap, the diffusion of the liquid can reach equilibrium at a fast speed, making the replacement particularly rapid. As shown in Figure 3, equilibrium is reached within 1 second, achieving 99.9% replacement, thereby further reducing the amount of liquid used. As shown in the figure, compared with the comparative simulation of the flow cell of the traditional microfluidic device, the amount of liquid required is only a few times the volume of the area facing the first wall 1 and the second wall 2. The traditional flow cell requires about five times. Referring to Figure 3, combined with the lower gap and smaller replacement ratio, the amount of reagent required is generally 1/100 to 1/5 of the traditional microfluidic solution depending on the size of the chip. In contrast, although the traditional microfluidic period diffuses quickly in the microfluidic device, it needs to be connected to the microfluidic device through a pipeline. The reagent efficiency in the pipeline is very low, which greatly weakens the advantage of the microfluidic device in saving reagents. If the function "1, drain the original liquid in the flow field" is utilized, first replacing it with gas and then filling it with liquid, the required amount may be lower, but the effect of the gas on the molecules on the chip needs to be considered.

In an optional embodiment, the first fluid includes one or more reagents with different components. Different reagents enter the flow field simultaneously or in a certain order. The first fluid usually refers to a relatively precious substance that is saved by various special settings in the present invention.

In an optional embodiment, the flow domain includes more than one area with different reagents attached, wherein the different areas are discrete in space, and different kinetic reagents can enter different flow domains separately or sequentially in a certain order as they dissolve.

In an optional embodiment, at least one wall is formed by other fluids that are incompatible with the effective fluid, and friction is reduced on these walls; at the same time, because the fluid wall occupies a certain volume, the consumption of the effective fluid is further reduced. Furthermore, by adjusting the volume occupied by the fluid wall, the fluid consumption of a very thin chamber can be achieved. Increasing the shear force to move a movable part of the system with greater power (such as using a more powerful motor) is much easier in terms of engineering design and implementation difficulty than increasing the pressure of the pump that can be used in traditional microfluidic systems and the sealing of the system. Since surface reactions or actions generally do not require a lot of liquid, for this embodiment, a layer of fluid on the surface is sheared with a large velocity gradient in a smaller space, which can achieve a cleaner and more thorough fluid replacement effect than flushing and replacing with a large amount of liquid.

In an optional embodiment, the liquid path structure also includes a heater, which can be arranged on the first wall and/or the second wall to heat the flow domain so that the temperature of the flow domain can change over time, thereby realizing temporal temperature change of the flow domain, which is beneficial to the reaction of reagents under different environments.

In an optional embodiment, the liquid circuit structure further includes a cooler for accelerating cooling.

In an optional embodiment, the flow domain is heated by a heater arranged on the first wall and/or the second wall, so that more than one temperature zone is generated in the flow domain to achieve spatial temperature change of the flow domain, which is beneficial to the simultaneous implementation of different reactions or multiple reactions.

Example 1

In one embodiment, a shear-driven fluid platform as shown in FIG4 is constructed, wherein a first wall 1 is arranged parallel to a second wall 2, with a certain distance between them as a flow domain 3, wherein the movement of the first wall 1 includes: translation basically parallel to the second wall 2, translation in a direction approaching or away from the second wall 2, and rotation relative to the second wall 2.

The side view of the shear-driven fluid platform is similar to Figure 1(a), and the top view is disc-shaped, and it is ensured that every point can be traversed by the flow domain by rotation. The second wall 102 is formed by the upward surface of the silicon wafer. The robot places the silicon wafer on the vacuum suction cup 114, and the suction cup drives the second wall 102 to start rotating, and the speed can be, for example, 1000r/min. The first wall 101 is a glass grinding disc that is conveyed to a position that is, for example, 100 microns away from the second wall 102 and parallel to each other.

The first fluid 106 is added to the middle channel of the first wall 101 through the inlet 104, and forms a flow area 103 between the two walls. The first wall 101 also starts to rotate, driving the fluid to form a shear motion on the surface of the second wall 102. At this time, the fluid continuously enters from the inlet 104, leaves the flow area 103 from the surrounding outlets, and is blocked by the waste liquid cover 128 and flows into the wastewater area.

In an optional embodiment, the first fluid is various reagents of the RCA cleaning method, which allows organic matter and metal ions to enter the flow domain by etching, dissolving, reacting with wafer surface contaminants, etc. without destroying the surface features of the wafer. They are:

1. APM, commonly known as SC1 cleaning solution, has a formula of NH ₄ OH:H ₂ O ₂ :H ₂ O=1:1:5-1:2:7, which uses oxidation and micro-etching to undercut and remove surface particles;

2. HPM, commonly known as SC-2 cleaning solution, has a formula of HCl: _H2O2 : _H2O = 1:1:6 to 1:2:8, which can dissolve alkali metal ions and hydroxides of aluminum, iron and magnesium. _In addition, the chloride ions in the hydrochloric acid react with the residual metal ions to form a complex that is easily soluble in aqueous solution, which can remove metal pollutants from the bottom layer of silicon.

3. SPM, commonly known as SC3 cleaning fluid, has a volume ratio of sulfuric acid to water of 1:3, and is a typical cleaning fluid used to remove organic pollutants. Sulfuric acid can dehydrate organic matter and carbonize it, while hydrogen peroxide can oxidize the carbonization product into carbon monoxide or carbon dioxide gas.

4. Diluted hydrofluoric acid, HF:H ₂ O＝1:2:10, is mainly used to remove oxides from special areas, etch silicon dioxide and silicon oxide, reduce surface metal, form silicon-hydrogen bonds on the surface of silicon wafers, and present a hydrophobic surface.

5.Ultrapure water, using ozonated water to dilute chemicals and rinse wafers after chemical cleaning.

RCA cleaning with additional megasonic energy can reduce the consumption of chemicals and DI water.

Specifically, the reagent is added so that it overflows the channel 104 and spreads to the surface of the first wall 101. Subsequently, the center point of the first wall 101 moves from the edge to the center of the circle and then to the edge on the surface of the second wall, so that the second wall 102 is repeatedly and comprehensively cleaned. Preferably, high-pressure gas can be used to physically impact the second wall 102 while cleaning. Finally, the robot arm clamps the second wall 102 away.

When the first wall is not present, the shape of the fluid on the second wall will be completely determined by the affinity between the two, so that the fluid forms a thicker liquid layer on the second wall, similar to a dewdrop on a lotus leaf. Therefore, by setting the hydrophilicity and hydrophobicity of the first wall 101 and the distance between the second wall 102, a thinner fluid layer between the two walls can be retained, and the fluid can be further guided to form a thinner flow domain.

In an optional embodiment, the rotation process of the first wall 101 and the movement process of the first wall 101 on the surface of the second wall 102 are conducive to the uniform distribution of the new fluid in the flow field 103, rather than causing more liquid to flow to places with less flow resistance due to some uneven manufacturing gaps.

At the same time, the first wall 101 can prevent the evaporation of the fluid, thereby preventing the damage of DNA or circuits caused by the drying of the fluid during the heating process. In addition, the first wall 101 is helpful to prevent waste in the process of adding fluid. If there is no first wall, when the second wall 102 rotates, the shear force generated causes the fluid to produce centrifugal motion and leave the flow field 103.

In an optional embodiment, the second wall surface 102 remains stationary, and the first wall surface 101 moves from the edge to the center of the circle, and then to the edge on the surface of the second wall surface 102 while rotating, traversing the second wall surface 102, so that the second wall surface 102 is fully cleaned. Since the chip structure is attached to the second wall surface 102, the fluid in the flow field 103 is driven to perform shear motion by the first wall surface 101, and the chip structure and the circuit structure attached thereto are kept stationary while cleaning and replacing the liquid, thereby reducing the impact of the movement on the chip structure during the cleaning and replacement process.

In an optional embodiment, the liquid inlet can be at the edge of the first wall very close to the flow basin, for example, the liquid inlet pipe is close to the first wall 101 instead of passing through it, and the liquid can also be sucked into the flow basin. In addition, the second wall 102 mentioned above can be a surface other than the silicon wafer that needs to be replaced, for example, it can be a glass chip or a biochip surface. For example, a gene sequencing chip. In addition, the first fluid 106 can also be other fluids, such as a formula of a dilute chemical method, a formula of an IMEC cleaning method, or even a dry gaseous formula, such as a thermal chemical gas or a plasma reaction gas. In addition, the first fluid 106 can be mixed with particles, such as aluminum oxide, silicon dioxide, cerium dioxide, zirconium oxide and diamond particles, to increase the cleaning effect. The particle size of the above particles can be 1-50 microns. In addition, the first fluid can be mixed with gas and liquid to increase the cleaning effect. In addition, the material of the grinding disc can be polyurethane, non-woven fabric or other composite materials. In addition, in the above embodiment, the distance is 100 microns, but the distance can be close to the silicon wafer, or a certain angle to contact the silicon wafer, and the fluid still exists between the two surfaces that are not absolutely smooth. In addition, the two planes can also be other shapes besides disks. In addition, the function can also be other fluid operation purposes besides changing the liquid, such as allowing the reagents to react in a smaller shear flow domain, such as crystal growth. In addition, the first wall surface can be larger than, or smaller than or equal to the second wall surface. The existing solution is to directly splash the chip surface through a water pipe, and the chip is in a rotating state. The amount of ultrapure water used in this solution is quite large, for example, 50mL per second. It is reported that TSMC's Hsinchu plant requires 150,000 tons of water every day. This solution uses 1% of the reagent usage of the current solution, which is 0.5mL per second or even less. At the same time, according to the fluorescence replacement experiment, it takes less time, but the effect is better.

In an optional embodiment, the inlet 104 is not in direct contact with the flow area 103. For example, the inlet 104 can be arranged near the flow area 103, and the first fluid 106 is adsorbed by the flow area 103 after passing through the inlet 104, and then introduced into the flow area 103.

In an optional embodiment, the inlet 104 is configured to be attached to a side edge of the first wall 101 .

In an optional embodiment, as shown in FIG5 , the first wall 101 remains stationary, and the second wall 102 rotates under the drive of the vacuum chuck 114, so that every point on the second wall 102 and the first wall 101 can be in the flow region 103. The first wall 101 and the second wall 101 are coaxially arranged, and the relative rotation of the first wall 101 and the second wall 102 enables the second wall 102 to be repeatedly and comprehensively cleaned.

In an optional embodiment, as shown in FIG. 5 , the second wall surface 102 remains stationary and the first wall surface 101 keeps rotating, so that the second wall surface 102 is fully cleaned.

As just mentioned, this embodiment can be used on any chip surface that needs to change liquid. In conjunction with FIG5 , the second generation sequencing scheme using SBS (sequencing by synthesis) is used as an example to further describe the liquid path structure characteristics provided by this embodiment. The technical solution using this embodiment may include the following steps:

1. Providing a first fluid through an inlet structure, wherein the first fluid includes a reagent capable of disconnecting an azide group to cause a first reaction between the first fluid and a biomolecule;

2. providing a second first fluid through the inlet structure, the second first fluid comprising a buffer reagent for cleaning the first first fluid and the product of the first reaction;

3. Providing a third first fluid through the inlet structure, wherein the third first fluid includes reagents of four bases, ACTG, so as to cause a second reaction between the third first fluid and the biomolecule;

4. Providing a second first fluid through the inlet structure for cleaning the third first fluid;

5. Record and determine the base type of the product of the third reaction on the chip;

Repeat steps 1 to 5 multiple times to obtain the base sequence of the single-stranded DNA based on the base types of the product of the third reaction.

In an optional embodiment, the outlet structure includes an area between the periphery of the disk on the first wall and the periphery of the disk on the second wall, enabling the first fluid to be discharged through the area. The operating method of the microfluidic path structure also includes providing a waste liquid collection structure 150 for collecting the discharged first fluid.

In an optional embodiment, the third first fluid further comprises dye groups corresponding to the bases.

In an optional embodiment, step 5 includes recording the fluorescence on the chip by sensing, and determining the base type by a basecall algorithm.

In an optional embodiment, the first wall surface and the second wall surface are coaxial disc structures in the vertical direction.

In an optional embodiment, the area of the first wall surface is greater than or equal to that of the second wall surface.

In an optional embodiment, the reaction time of the first reaction is 1 minute.

In an optional embodiment, the volume of the second first fluid is three times the volume of the flow basin.

In an optional embodiment, the volume of the third first fluid is 1.5 times the volume of the flow basin.

In an optional embodiment, the second reaction is carried out at a temperature of 55° C., and the reaction time of the second reaction is 1 minute.

Specifically, the steps include:

1. Provide a patterned chip (glass or silicon chip) with a certain depth (e.g., 50 microns) as the second wall 102, wherein the pattern portion makes the second wall 102 have alternating hydrophilic and hydrophobic regions. Single-stranded DNA can be fixed on the hydrophilic region, and the DNA binds to the base with a distinguishable signal. The hydrophobic region is covered with a hydrophobic substance, such as HMDS. At this time, the first wall and the second wall are coaxial disc structures in the vertical direction, and the area of the first wall is greater than or equal to that of the second wall.

2. Drop an excision reagent 161 that can disconnect the azide group, such as a triphenylphosphine solution, from the inlet 104, with a volume equivalent to 1.5 times the volume of the basin, to clean the single-stranded DNA. The excision reagent flows from the inlet to the outlet by means of rotational centrifugation, or by means of pressure difference (for example, the gas environment at the inlet has a pressure of 50 kPa, and the outlet is open to the atmosphere and the pressure is 0), or a combination of the two. The outlet can be directly in contact with the environment without being connected to the pipeline, and the droplets dripping from the edge are collected by negative pressure.

3. The excision reagent 161 occupies the flow field 103, the chip is cleaned, and the reaction is allowed to proceed for 1 minute to prepare for the next step of synthesis. The buffer 162 enters the flow field 103 through the inlet 104, with a volume equivalent to three times the volume of the flow field, to clean the excision reagent and the reaction product. Because the area of the first wall is greater than or equal to the second wall, the excess reagent forms droplets from the joint of the two walls, drips under the action of gravity, and is collected by the waste liquid collection structure below.

4. A synthetic reagent 163 containing four bases ACTG and corresponding dye groups is passed through the inlet 104 into the flow basin 103 (each base carries a distinguishable signal, such as a fluorescent group of a different wavelength, connected by an azido group, for example, A, C, T and G are connected to the dyes ROX, CY5 from Thermo Fisher Scientific, Alexa Fluor 532 from Thermo Fisher Scientific and iFluor 700 from AAT Bioquest, respectively. At the same time, the 5' end is also modified by an azido group, so that the single-stranded DNA that the synthetase can bind to stops after synthesizing one base and cannot bind to the next one).

5. After the synthesis reagent 163, which is equivalent to 1.5 times the volume of the watershed, has traversed the chip, 99.9% of the replacement is completed, and the pressurization device and/or rotation are stopped. After the temperature rises to 55 degrees and stays for one minute, the synthesis reaction synthesizes bases with distinguishable signals onto each DNA single strand. Usually a single strand will have multiple copies in a hydrophilic area, so that a stronger fluorescent signal of a single base can be formed, for example, controlling the replication time to form 200 copies.

6. Introduce the buffer solution 162 into the flow basin 103 through the inlet 104 to clean the synthesis reagent and prevent the fluorescent signal inside from being confused with the signal synthesized on the DNA during sensing.

7. Through taking photos and other sensing methods, the fluorescence emitted by each point on the chip is recorded, and the basecall algorithm determines the type of base just synthesized.

Repeat steps 2-7 35-300 times. After the excision reagent, the 5' end can bind to a new base. After recording the different base information, the base sequence at each point is finally obtained using a software algorithm, and these sequences are finally pieced together into the base sequence of the sample.

In some optional embodiments, a step may be added between steps 6 and 7: In order to prevent some copies of the same hydrophilic region from not participating in the reaction in step 4, a synthetic reagent 163 containing four bases ACTG and corresponding dye groups is introduced into the flow field 103 through the inlet 104 (each base carries no distinguishable signal, but the 5' end is also modified with an azide group, so that the DNA single strand that the synthesizer can bind stops after synthesizing one base and cannot bind to the next one). After the synthetic reagent 163 equivalent to 1.5 times the volume of the flow field has traversed the chip, 99.9% of the replacement is completed, and the pressurizing device and/or the rotation is stopped. The buffer 162 is introduced into the flow field 103 through the inlet 104 to clean the synthetic reagent.

In some optional embodiments, a step may be added between steps 6 and 7: In order to avoid adverse effects on DNA during the photographing process, the protective reagent 164 is introduced into the flow basin 103 through the inlet 104 to replace the original reagent, and then transferred to the optical machine to start photographing.

In some optional embodiments, the buffer 162 of different steps may be composed of different components.

If there are multiple samples, each one needs to be combined with a specific DNA fragment before entering the chip to facilitate subsequent splitting.

According to the above embodiment, the gap between the first wall 101 and the second wall 102 is 10 microns, and the flow rate of the fluid in the flow field is 468uL/min. At this time, when the inlet diameter is 0.8mm, the maximum pressure is 58kpa, which is less than the system pressure limit of 100kpa.

In contrast, the traditional flow cell structure is shown in Figure 1(c), where the upper and lower surfaces are encapsulated into narrow sheets, and the inlet and outlet are connected by pipes. The gap between the surfaces is 20 microns, and the flow rate in the flow cell is 936uL/min. At this time, when the inlet diameter is also 0.8mm, the maximum pressure is as high as 316kpa, which is much greater than the maximum pressure limit of the system and is difficult to achieve. For example, the UV glue forming the flow channel may open, and the seal may also leak. Therefore, the traditional implementation method usually sets the gap at 50 microns. Compared with the present embodiment, the basin thickness differs by 5 times, has a high reagent consumption, and is not conducive to rapid liquid replacement. Therefore, when the liquid path structure according to the present embodiment is applied to the SBS method, the amount of fluid used can be reduced by at least five times, which is conducive to reducing reagent consumption and achieving rapid liquid replacement.

The above two examples are given for the cleaning of the chip during production and the replacement of reagents for the SBS reaction. In fact, it is just a platform for operating fluids. Any fluid operation that needs to reduce the amount of fluid used and the pressure requirement for surface physical or chemical reactions can similarly adopt the liquid path structure in the above embodiment, without exceeding the scope of the technical solution of the present application. The principle is that because the type of fluid used is consistent with the replaced method, it does not interfere with the original physical action (such as washing silicon wafers) or chemical action (such as SBS gene sequencing), and only allows the original reaction to be carried out under lower pressure and less reagent. Further, since the effective substances that need to act on the surface (such as corundum in water or bases in reagents) are very limited, such as gene sequencing, the substances that need to react are only equivalent to the bases contained in 2 microns of reagents. Therefore, when the traditional technical solution uses a flow cell with a thickness of 50 microns or more, the fluid with a thickness of at least 48 microns does not participate in the reaction and is wasted. The liquid path structure of this embodiment can make the liquid thickness extremely low while enabling the reagent to produce a more effective effect through the shear flow field.

Example 2

In one embodiment, a shear-driven fluid platform as shown in FIG. 6( a) is constructed, wherein the first wall 201 and the second wall 202 include curved surfaces to form a sleeve shape, wherein one of the first wall 201 and the second wall 202 forms an outer cylinder and the other forms an inner cylinder, and a flow domain is formed between the two.

The two surfaces in relative motion are changed from planes to curved surfaces to form a sleeve shape, which is also traversed by rotation. The second wall 202 is an outer cylinder, and the first wall 201 is an inner cylinder. The height of the inner cylinder is lower than that of the outer cylinder. When adding liquid, it will be thrown onto the cylinder wall and flow down into the flow basin. The spacing between the inner and outer cylinders is 2mm. The inner cylinder can be rotated by a control mechanism 212, and the temperature can be controlled by a heater 208. The magnetic rack 209, the fan 210 and the camera 211 are used to attract magnetic particles, ventilate and obtain visual information such as fluorescence intensity. Traditional equipment requires a large amount of reagents and requires professional manual intervention and a special place, such as in a wet laboratory. Although traditional microfluidic equipment uses less reagents, it is more expensive and less flexible. It can only be used for one reaction purpose, and its reliability is questionable. This embodiment allows reagents to react and replace quickly in the shear flow basin, and different reaction purposes can be achieved by replacing reagents. The instrument has high stability and both are achieved.

Specifically, since there is only relative rotation between the two walls, there is no complex operation such as transfer, splitting, merging, etc. in traditional microfluidic devices, which makes the instrument more stable.

In the device constructed in this embodiment, a curved ultra-thin chip (the chip thickness is less than 100 microns and has a soft property) can be arranged on the second wall surface 202 to implement the silicon wafer washing and gene sequencing operations as described in Example 1. In addition, the device constructed in this embodiment can also be used for other reaction processes.

In conjunction with FIG. 6 , the characteristics of the liquid path structure provided in this embodiment are further described by taking the use of the device constructed in this embodiment to replace Roche's Cobas Liat system for nucleic acid determination as an example. The specific implementation steps are as follows: the multiple reagents encapsulated are controlled by the control mechanism 212 (a memory metal that gradually restores its original shape when heated) to move the reagent bag from one direction to another, and sequentially pass through the cutter 213. The multiple first fluids 206 encapsulated in the bag flow down along the cutter 213 as the bag breaks and are thrown into the shear flow region 203 between the two walls. First, add the sample, a drop of the buffer solution containing oral epithelial cells in the matching dropper, about 20 microliters, and the sample preparation procedure is skipped here. Then, the bag of PBS buffer and proteinase K is cut by the cutter 213 and enters the flow region 203. The second wall 202 is heated to 40 degrees by the heater 208, and the control mechanism 212 (micro motor) controls the first wall 1 to mix the two with the sample at a speed of 30r/min. The control mechanism 212 controls the scratching of the lysate, incubates it at 50°C in the shear flow field for 5 minutes, and stops rotating. The motion control mechanism 212 controls the scratching of the isopropanol magnetic bead suspension, and the second wall 202 is kept at 50 degrees. The control mechanism 212 mixes at a speed of 30 r/min for 30 seconds and then stays for 5 minutes. The control mechanism 212 rotates the first wall 201 at a speed of 30 r/min and brings the magnet close, and the magnetic beads are attracted. After 1 minute, the control mechanism 212 opens the outlet 205 and keeps rotating, and the liquid flows out under gravity control. The outlet 205 is closed, and the magnetic beads are washed and eluted in the same way. The control mechanism 212 removes the magnetic rack 209.

In this process, nucleic acid is first released from the cells, then adsorbed to the magnetic beads, and separated from other liquids by the attraction of the magnetic rack 209 during elution. After other liquids are discharged, the nucleic acid material to be tested is obtained. When the volume of each reagent is at least twice the volume of the basin, it can participate in the reaction normally, and the total volume can be less than 1 mL.

Next is the amplification phase. UNG is mixed at 37°C for 5 minutes to digest the PCR contamination products. The temperature is raised to 95°C to inactivate the UNG enzyme and denature the DNA. The temperature is set to 60°C for amplification. This process is cycled and a photo is taken after each cycle. The fluorescence intensity is determined by analyzing the average grayscale of the image. Three experiments were conducted using fresh human whole blood samples treated with EDTA. The results are shown in Figure 7.

It can be seen that after 25 cycles, the positive sample and control signals are significantly different.

In an optional embodiment, the temperature of the second wall 202 can be changed over time, or multiple temperature zones can be set on the first wall 201 or the second wall 202, and spatial temperature change can be achieved by rotating the reagent to different temperature zones, as shown in Figure 6(b).

In addition to nucleic acid assay reactions, other reactions that require the addition of multiple reagents into the shear flow field are also possible.

In addition, in addition to using a knife to cut open the sealed reagent bags, some premixed liquids can also be provided.

In addition, oily reagents can be packaged in bags that are soluble in water, and aqueous reagents can be packaged in bags that are soluble in oil, and then dissolved using corresponding liquids.

Alternatively, a mechanical structure such as a perforated plate may be used to sequentially squeeze the reagents in the bag into the flow field.

In addition, freeze-dried reagents can also be added to the shear flow area in sequence according to the reaction order to save reagents and facilitate transportation.

Furthermore, by arranging a heater on the first wall 201 or the second wall 202, a plurality of temperature zones are generated in the flow basin 203. As shown in FIG6(b), different reagents are moved to different temperature zones in the flow basin by relative rotation between the inner cylinder and the outer cylinder to achieve circulation in space or time. In addition, it can also be used in other reaction or detection scenarios that meet the conditions of this patent and require reagent saving or rapid reaction, such as the detection of a certain component in sewage.

FIG6(c) is a schematic diagram of the instrument of the prior art Roche Cobas Liat system. False positives occurred during the testing of the Cobas SARS-CoV-2 and A/B influenza nucleic acid tests by the Roche Diagnostics Cobas Liat system. There are two reasons for this:

1. Test tubes may occasionally leak and cause light path obstruction in the Cobas Liat analyzer, resulting in abnormal PCR growth curves. This may lead to invalid or false positive results, especially for influenza B testing. The FDA added that if the test tube does leak, subsequent testing may increase the possibility of false positive results for influenza B.

2. Abnormal PCR cycles in the reaction tubes may produce abnormal PCR growth curves, resulting in false positives. The FDA said this problem is sporadic and may be caused by hardware positioning, volume movement, and curve interpretation. This problem may cause false positives for all analytes in the run.

In contrast, the device constructed in this embodiment has higher reliability, because Cobas Liat needs to squeeze and grind the bag storing the reagent, which not only takes a certain amount of time, but also brings reliability problems (the bag cannot be broken during grinding). Manufacturing reliability problems are common problems of microfluidic devices. In the device constructed in this embodiment, the bag is simply scratched, which reduces the probability of reliability problems and speeds up the mixing speed. In addition, in the prior art Cobas Liat, there is a need for hardware positioning due to the inconsistent functions of the reagents in each area. In the device constructed in this embodiment, the reagents are uniformly introduced into the shear flow zone and the position is controlled by rotation, without the need for hardware positioning, which further reduces the possibility of reliability problems.

In summary, in the liquid path structure of this embodiment, different flow domains are mixed and reacted through the shear flow field, and the flow domains are open systems with simple structure, high reliability and convenient manufacturing.

Example 3

Further, the shear-driven fluid platform can be in the form of FIG8 , where a moving wall is a liquid. In some current biological reactions, such as the prior art shown in FIG8 (a), the flow cell of the microfluidic device used in gene sequencing has a minimum gap of only 50 microns. Since the pressure and the gap are in a quadratic negative correlation, if the gap is further reduced, the problem of excessive fluid pressure will be faced, and only a too low flow rate can be used, which reduces the time to complete the task. But in fact, because it is a surface reaction (the reaction surface in the schematic diagram is the bottom of the channel), the chip does not need a 50-micron reagent layer. According to theoretical calculations, only 2 microns are required, so 48 microns are wasted. In order to further save reagents, the shear-driven fluid platform of FIG8 introduces a second inlet 304 and a second fluid 307, and the second fluid 307 forms a fluid wall, so that the effective reagent forms a shear flow in the thin flow domain composed of the second fluid 307 and the bottom surface, so that only a part of the area in the 50-micron channel is the effective reagent flowing, and the flowing reagent can cover the bottom of the channel, so that the purpose of speed and saving effective reagent can be achieved at the same time. As shown in Fig. 8(c), the separation interface 361 between the two fluids is drawn in both Fig. 8(b) and Fig. 8(c).

The second fluid flows into the flow domain from the second inlet, flows out from an outlet of the outlet structure, and shares an outlet with the first fluid, or flows out from another outlet of the outlet structure, and uses a different outlet with the first fluid, wherein the second fluid and the first fluid are laminar flows in the thin flow domain, and the second fluid occupies a certain space in the thin flow domain so that the required amount of the first fluid is further reduced.

In this embodiment, reactants are fixed on the bottom surface of the channel.

Furthermore, FIG8 shows the flow rate thermal diagram scales of FIG8( b) and FIG8( c), wherein the flow rate magnitudes of the various sections in FIG8( b) and FIG8( c) are shown in different colors, wherein each section is an isosurface of the volume fraction of the first fluid 306.

Taking the use of the device to replace Illumina's flow cell system for DNA sequencing as an example, the specific implementation plan is as follows: in a 50-micron microchannel, there is an upper inlet 304 in the 3D figure that pumps 98 gasoline produced by Sinopec to form a second fluid 307, and the hydraulic environment satisfies the Reynolds number of less than 1000. The lower inlet introduces the first fluid 306, which is fluorescent dNTP. It is located below the second fluid 307 and close to the bottom of the pipe with DNA attached, which is convenient for reaction. Under the scale of microflow and laminar flow conditions, the two liquids flow clearly with a clear interface in the middle. As shown in FIG8(b), the separation interface 361 in the figure is the interface between the first fluid 306 and the second fluid 307. The flow rate of the second fluid 307 is adjusted to, for example, 9 times the flow rate of the first fluid 306, and the flow drives the first fluid 306 in the thin flow domain to perform shear motion, and provides much smaller friction resistance than the solid wall, so that the energy required for the flow of the first fluid 306 is reduced. The second fluid 307 occupies most of the volume, making the total amount of the first fluid 306 required smaller. However, because the thickness of the first fluid is greater than 2 microns, it does not affect the reaction. After two seconds of liquid feeding to complete 99.9% of the reagent replacement, both are controlled by the solenoid valve to stop liquid feeding, and the first fluid 306 reacts with the bottom surface of the tube (biochip) for 1 minute. Both resume liquid feeding at the same time, the first fluid 306 flows into the waste liquid tank, and the second fluid 307 is recovered from another outlet because it is incompatible with the aqueous reagent. The cleaning buffer is introduced into the pipeline for cleaning. The second wall 302 (chip) is taken to the optical machine for photography. The reagent is removed by another first fluid 306, and the next cycle is carried out to test the type of the next base. The amount of reagent used in this method is only 10% of the original amount, because the pumping volume ratio of the incompatible fluid to the first fluid is 9:1.

Since the fluorescent dNTP reagent is the most worth saving reagent in the SBS sequencing process, this embodiment is described in detail using this as an example. Further, the types of reagents, conditions, and sequence of the reaction can all refer to the step description in Example 1 above. The SBS reaction principle itself does not fall within the scope of protection of this patent and will not be repeated.

From the perspective of the flow field space that constrains the first fluid, the second fluid can be regarded as a "wall" or a "fluid wall". The principle and advantage of this embodiment is that when at least one wall is formed by other fluids that are incompatible with the effective fluid (i.e., the first fluid), friction is reduced on these walls. At the same time, because the fluid wall occupies a certain volume, the consumption of the effective fluid is further reduced. According to the method of this embodiment, the chamber does not need to be made very thin. By adjusting the volume occupied by the fluid wall, the fluid consumption of a very thin chamber can be achieved. When the chamber can be very thin, the pressure increases in geometric series, which brings more problems to the system that cannot be solved. Then, increasing the shear force requires greater power (such as using a more powerful motor), which is much easier and more reliable in terms of engineering design and implementation difficulty than increasing the sealing of the system that can be used for traditional microfluidic systems. Finally, this control method is more intuitive, reduces the threshold for research and development and use, and does not require major changes to the system. This is feasible in principle because surface reactions or actions usually do not require a lot of liquid, only a layer of fluid on the surface, and shearing with a large velocity gradient in a small space is cleaner and more thorough than flushing and replacing with a large amount of liquid. According to the improvement of this embodiment, when the chamber is made thinner and requires a large pressure, which exceeds the sealing degree of the microfluidic system (for example, 100Kpa for the sequencing system), a "fluid wall" can be used to define a smaller flow domain, thereby reducing manufacturing costs, releasing system performance, and making microfluidic devices easier to manufacture and use.

In an optional embodiment, the inlet structure, outlet structure and flow field 303 (reaction chamber) may not be channels, but other equivalent flow fields, or structures or components with similar fluid behavior, such as the part connected by the two inlets 341 and 342 shown in FIG9 (a), and the outlet 305 are all thin sheet structures. In addition, the inert second fluid 307 may not undergo macroscopic flow, but only occupy a certain volume of the flow field. This makes it possible to form a very fine liquid path without requiring too high a manufacturing process. However, the interface is still in a flowing state, and the movement of the first fluid 306 is still a shear movement. In addition, the outlet can be connected to the same container, and the reagent and the second fluid are separated by density difference at a later stage. In addition, each inlet or outlet of the device can be a microfluidic chip, or similarly, a baffle 319 is set in the middle of the original chip to achieve better hydraulic conditions and form a clear laminar flow. As shown in FIG9 (b). In addition, the reaction can be other reactions that require saving reagents and emphasize surface replacement effects. In addition, the second fluid 307 can also be a relatively cheap liquid, such as other oils. It can also be a liquid that is miscible with the first fluid, such as pure water, to form a laminar flow. In addition, the second fluid 307 can also be other pump speeds, so as to occupy different volume fractions in the pipeline or thin sheet flow field, and achieve different degrees of reagent saving effects. In addition, in order to speed up, both the first fluid 306 and the second fluid 307 can be connected to a pump. In addition, there can be multiple inlets. If biomolecules are fixed on the upper and lower surfaces of the channel, three inlets can be used, with the upper and lower being reaction reagents, and the middle being the second fluid 307 occupying a certain volume.

Specifically, as shown in FIG9(b), the first fluid 306 enters the flow domain through the first inlet 341 and flows out from the first outlet 351, and the second fluid 307 enters the flow domain through the second inlet 342 and flows out from the second outlet 352. The first fluid 306 and the second fluid 307 form a phase-separated laminar flow under the action of the density difference and the baffle 319. The second fluid 307 does not undergo macroscopic flow, and the first fluid 306 performs shear motion driven by the second fluid 307.

This embodiment describes how to save a certain reagent by way of example. The specific reagent type, conditions, and sequence vary according to the needs. For example, it can be a synthetic reagent containing fluorescent bases in SBS. The open system makes these operations simpler, saves precious reagents and samples, and does not require major changes to the original system or increase the upper limit of the system pressure.

The above-mentioned technical solution of forming the fluid wall by the second fluid is suitable for both closed pipelines and open flow domains formed by the first wall and the second wall. For the latter, as long as the pressure of the introduced fluid is not greater than the surface tension.

Example 4

In one embodiment, a shear-driven fluid platform as shown in FIG. 10 is constructed, and the characteristic of the Couette-like flow field that "the fluid between the first wall and the second wall follows the moving wall" is utilized. Similar to Example 2, the first fluid 406 reagent can be mutually translated between different temperature zones by the translation of the first wall 401. There are insulation blocks 418 (for example, made of ceramics) between the partitions, and the places without insulation blocks 418 can be set to different temperatures by the heater below. And at least part of the surface of the second wall 402 is made into a hydrophobic form (for example, silicon wafers are treated with silane, the first wall 401 is made of PET, and aqueous reagents are used in the flow field 403), so as to form a phenomenon similar to "pinning line", so that the liquid can be confined to a certain area near the first wall 401, and the liquid pushed out of the flow field 403 by the shear flow field will be sucked back into the flow field 403 by the surface tension. With the movement of the first wall 401, it moves completely without remaining on the surface. As shown in FIG. 11, the fluid can move like a chess piece on the frame line of the chessboard. The first wall 401 and the second wall 402 may have a larger area, with more functional partitions, on which different freeze-dried reagents are fixed to achieve different reactions, or multiple reactions can be performed simultaneously.

In an optional embodiment, as shown in FIG. 11 , the second wall surface 402 is divided into a plurality of functional partitions, and the functional partitions of the second wall surface 402 are distributed in two dimensions.

The difference between this embodiment and embodiment 2 is that the liquid in the flow domain 403 can not only move along with the movement of the first wall, but also form a phenomenon similar to a "pinning line", so that the liquid can be confined to a certain area near the first wall 401, and the liquid pushed out of the flow domain 403 by the shear flow field will be sucked back into the flow domain 403 or near 403 by the surface tension.

Specifically, different freeze-dried reagents are fixed on each different functional partition on the second wall 402, and different reactions can be achieved when the flow field 403 moves above different functional partitions. Alternatively, the flow field 403 is located above multiple different functional partitions at the same time, so that multiple reactions are carried out simultaneously. Taking the QPCR process as an example, the timing and dosage of the reagents are similar to those in Example 2. The difference is that in Example 2, the liquid reagent is added to the flow field and then the excess reagent is removed. In this case, the liquid is moved to the functional area to dissolve the freeze-dried reagent fixed on the functional area for reaction. A similar solution now is digital microfluidics. In comparison, the equipment of this solution is simpler, and can also achieve the purpose of being fast and saving more reagents.

The difference between this embodiment and the existing digital microfluidics is that the digital microfluidics does not have a moving "chess", but is driven by electrical energy. This method is relatively expensive, the droplets are relatively large, and the chip gap is also relatively large. The current may also cause unnecessary effects on the reaction, and the life span is also limited.

Taking the use of the device to replace Roche's Cobas Liat system for nucleic acid determination as an example, the specific implementation scheme is that the second wall 402 uses a silicon wafer treated with hydrophobic material silane, and the first wall 401 uses a PET surface. The distance between the two is 50 microns, and a 50-micron gasket is placed on the first wall 401 to raise the PET surface to a suspended state. The size of the first wall 401 is 1cm×1cm, the size of the second wall 402 is 5cm×5cm, and the size of each functional area is 1cm×1cm. All movements are controlled by the control mechanism 412. First, add the sample, and a drop of the buffer solution containing oral epithelial cells in the matching dropper is placed in the sample addition area of the second wall 402, and the first wall 401 is moved past, and the sample is sucked into the flow basin. The sample preparation procedure is skipped here. Next, move the first wall 401 to the initialization area containing PBS buffer and proteinase K premix, and the liquid enters the flow basin. The first wall 401 is heated to 40 degrees by the heater 408 and stays for one minute. Next, move the first wall 401 to the lysis area containing the lysate freeze-dried powder. Move the first wall 401 clockwise in the surrounding four squares to mix it and then heat it to keep it at 50 degrees for 5 minutes (there are no functional divisions in the surrounding four squares). Next, move the first wall 401 to the synthesis area containing the isopropanol magnetic bead freeze-dried powder. Move it clockwise in the surrounding four squares to mix it and then stay for 5 minutes. Next, move the first wall 401 to the magnetic area, and the magnetic beads are attracted. After 1 minute, move the first wall 401 to the waste liquid area. The waste liquid has fibers that absorb the original reagents, while the magnetic beads remain in the magnetic area. Then go to the cleaning liquid area to inhale 50 microliters of liquid (similar to the sample addition process). After repeating several times to wash the magnetic beads, go to the elution area to inhale the liquid, and return to the magnetic area to wash and elute the magnetic beads. Move the first wall 401 to the UNG area, mix it at 37°C for 5 minutes to digest the PCR contaminated products. Move the first wall 401 to the 95°C zone to inactivate the UNG enzyme and denature the DNA. Move the first wall 401 to the 60°C zone for amplification. Cycle this process and take pictures after each cycle or multiple consecutive cycles to determine the fluorescence intensity by analyzing the average grayscale of the picture.

In addition, other liquid operation methods that can be used for digital microfluidics, such as "mixing", "reaction", "detection", and "separation", can be used in this technology. The methods are basically the same and will not be repeated here. In addition, the surface can also use other surfaces that can achieve the same purpose, such as glass with hydrophobic treatment as the second wall 402, aluminum as the first wall, and an aqueous reagent in the flow field. In addition, the suspension height can be other heights, and a gasket can be used without the need for a gasket. A gap of about 50 microns can be obtained by using the force of the liquid itself, or a gap can be obtained by using other mechanical positioning structures.

This embodiment describes the features of the liquid circuit structure provided by this embodiment by way of example through the PCR process, wherein the reaction process and reaction timing are irrelevant to the fluid operation (for the fluid operation, other reagents can be used instead without affecting the final operation effect). Other devices using digital microfluidics or microfluidics can also be substituted if the process is compatible with the setting of this embodiment, such as environmental detection or SBS gene sequencing.

The technical solution of this embodiment adopts an open system, which will not cause the liquid to be difficult to move due to excessive pressure caused by viscous liquid, which is conducive to simplifying the equipment and making the liquid layer thinner, thereby achieving the purpose of speed and saving reagents.

Example 5

In one embodiment, a shear driven fluid platform as shown in FIG. 12 is constructed.

Example 6

In one embodiment, a shear-driven fluid platform as shown in FIG. 13 is constructed. First, there needs to be sufficient fluid at the inlet, otherwise other unnecessary fluids, such as air, will be sucked in. The Couette field is a zero-pressure field, so the flux inside is equal to the cross-sectional area multiplied by the average velocity. In reality, there is a deviation from the ideal situation, and there may be pressure, and sometimes fluctuations. When the gap is too narrow, it is difficult to actually measure. Therefore, the way to ensure safety is that there is always excess liquid at the inlet. In terms of operation method, the amount of liquid must exceed the amount required by the system, and the excess liquid can be discharged from the system by bypass. One way of bypassing is to connect the liquid at the inlet or outlet to the waste liquid bucket along the device or by suction, as shown in FIG. 13 (a). The second way is that one wall is wider than the other wall, and the excess liquid can eventually leave the shear flow domain through the relative movement of the wall, as shown in FIG. 13 (b). The advantages of this solution are saving reagents, fast and cheap equipment, and no expensive and complex pipeline design is required.

Specifically, as shown in FIG. 13( a ), the excess first fluid leaves the flow field 603 at the inlet 604 through the bypass device 617 and enters the waste liquid barrel 615 .

Figure 13(b) shows a top view of a portion of the flow basin 603, wherein the widths of the first wall 601 and the second wall 602 are different, and excess first fluid leaves the flow basin 603 through the bypass device 617 with the help of the relative movement between the first wall 601 and the second wall 602, flows to the outlet and enters the waste liquid barrel 615.

This embodiment can be used alone or as a supplement to the above embodiments. For the technical solution of this application, embodiments 1, 2, 3, and 5 can be used in combination with embodiment 6 to drain the excess reagents in the flow basin. The open system makes it easier to discharge reagents, and there is no need to make major changes to the original system. Because the number of channels in the discharge system has increased, the pressure generated in the system is lower at the same flow rate, and there is no need to increase the upper limit of the system pressure.

Example 7

In one embodiment, a shear-driven fluid platform as shown in FIG. 14 is constructed, and fluid is introduced in a time- or space-discrete manner through an inlet structure, including:

In an optional embodiment, the inlet structure includes an inlet, into which each first fluid is introduced at different times, such as 761, 762 and 763 in Figure 14(a).

Alternatively, when each first fluid is introduced into the inlet at the same time, an incompatible fluid is used to separate each first fluid so that each first fluid will not mix with each other before entering the flow domain, as shown in 764, 765 and 766 in Figure 14(b).

In an optional embodiment, the inlet structure includes more than one inlet, and each first fluid is introduced through a different inlet so that the first fluids will not mix with each other before entering the flow field, such as 741, 742 and 743 in Figure 14(b).

The shear-driven fluid platform device can be in the form of Figure 14. The fluid supply method is changed to different fluids being discrete in space or time. Many medical instruments require a long time (e.g., half an hour) and a large amount of reagents/buffers to clean the pipelines. The reason is that the velocity of the fluid layer in contact with the tube wall is 0. Therefore, to completely replace this layer of fluid, it can only be done by diffusion. Therefore, although the reagents required inside the microfluidic device are very few, the reagents entering the microfluidic device are impure due to the mutual mixing of reagents in the pipeline of the microfluidic chip. The pipeline needs to be cleaned first, so the vision of saving reagents in the microfluidic chip cannot be well realized. In the shear-driven open microfluidic platform, we do not need a pump to directly provide pressure for the microfluidic chip, so the common pipeline connected to the flow field is not necessary. Therefore, we designed a spatially discrete liquid supply method, the purpose of which is to prevent different types of liquids from mixing in space before entering the microfluidic chip, so as to avoid cross-contamination and cleaning of the system common channel to the greatest extent, making the reagent economy better. As shown in FIG14( a ), the injection is carried out in a time-discrete manner, FIG14( b ) the injection is carried out in a space-discrete manner, and FIG14( c ) the injection is carried out in both a time-discrete and a space-discrete manner.

Specifically, as shown in FIG. 14( a ), reagent 761 , reagent 762 , and reagent 763 are allowed to enter the flow basin 703 in sequence through the same inlet 704 .

As shown in FIG. 14( b ), reagent 764 , reagent 765 , and reagent 766 are allowed to enter the flow field 703 simultaneously through the same inlet 704 , wherein reagent 764 , reagent 765 , and reagent 766 are gases or immiscible liquids.

As shown in FIG. 14( c ), reagent 767 is allowed to enter the flow basin 703 through inlet 741 , reagent 768 is allowed to enter the flow basin 703 through inlet 742 , and reagent 769 is allowed to enter the flow basin 703 through inlet 743 .

According to this embodiment, it is necessary to ensure that the inlet liquid supply is not too much without pressure and sealing, otherwise it will cause accumulation; it cannot be too little, otherwise it will cause the chip to dry out and air to mix in, unless the air is mixed in for the purpose of achieving more thorough cleaning. And ensure that the outlet is unobstructed, otherwise the liquid at the inlet has no way to enter the flow basin. Usually, the inlet needs to be supplied with a slightly excessive amount of liquid. As shown in Figure 14 (d), the inlet 704 can be widened.

In an optional embodiment, as shown in Figures 15(a), 15(b) and 15(c), one end of the pipeline in the flow field is an open pipeline and the other end is a closed pipeline. The pipeline with one end closed is conducive to increasing the pressure inside the pipeline and reducing the amount of reagent introduced at the inlet structure.

The present embodiment can be used alone, and can also be a supplementary means of the above embodiments. Embodiments 1, 2, 3, and 5 can be combined with embodiment 7 for application. In combination with the introduction method of reagents in the shear-driven fluid platform constructed by embodiment 7, the liquid inlet in the river basin becomes more efficient. The open system makes it simpler for reagents to enter the river basin, and there is no need to make major changes to the original system. For an open river basin, when the channels for fluid introduction increase, reagents can be added directly through different entrances to avoid large-scale use and cleaning of common pipelines, which consumes time and reagents. When it is not directly added dropwise but through a dedicated pipe, the sample volume in the river basin can be controlled by pressurizing the inlet (for example, maintaining an air pressure of 50kpa), and the metering pump at the outlet sucking a certain amount of liquid, and there is no need to set multiple pumps at the inlet, which is conducive to the reduction of reagent usage and pressure, and reduces the use of common pipelines.

Example 8

In one embodiment, a shear-driven fluid platform as shown in FIG. 16 is constructed, in which the sum of the cosine values of the contact angles of the first wall 801 and the second wall 802 with the first fluid 806 is greater than or equal to zero.

The shear-driven fluid platform device can be in the form of Figure 16, so the system packaging can be omitted, and different walls can be directly manipulated to approach or even contact each other, and the fluid can be constrained in the system through surface tension or other means. The advantage of this design is that it avoids the high cost of packaging, and the liquid channel is formed by the surface shape, properties or manipulation of the gap between the approaching walls. Because the movement of the liquid is controlled by shear force rather than the pressure or capillary force of traditional microfluidics, it is no longer necessary for the system to have dimensional stability under high pressure and very strict dimensional consistency of the passage to make the liquid reach the specified place at the specified time to ensure the consistency of the product results. Instead, it can be controlled by controlling the movement of the wall to control the start and stop of the shear force, so that it is more fault-tolerant. This improvement reduces the difficulty of manufacturing and quality control, which is a key obstacle to the popularization of microfluidic devices.

To achieve this, the first wall 801 and the second wall 802 need to have the property of retaining the reagent. If it is a liquid, the sum of the cosines of the contact angles of the liquid on the two walls needs to be greater than 0, as shown in Figure 16. When the sum of the cosines of the contact angles of the liquid on the two walls is greater than 0, and the affinity to one of the walls is very poor and/or the shear rate is not high, such as a hydrophobic surface and an aqueous reagent, the liquid squeezed out of the flow field by the shear force will be sucked back into the flow field.

Specifically, FIG. 16( a ) shows a side view of the flow domain 803, where the contact angle between the first fluid 806 and the first wall 801 is α, and the contact angle between the first fluid 806 and the second wall 802 is β. The sum of the cosines of the contact angles of the first fluid 806 on the two walls is cosα+cosβ≥0. FIG. 16( b ) shows a top view of the flow domain 803, where the width of the first wall 801 is greater than that of the second wall 802, and when cosα+cosβ≥0, the range of the flow domain 803 is limited to the range of the first wall 801.

This embodiment can be used alone or as a supplement to the above embodiments. Embodiments 1, 2, 3, and 5 can be used in combination with Embodiment 8. The shear-driven fluid platform constructed based on Embodiment 8 makes the assembly of the device cheaper and more fault-tolerant. Traditional microfluidic devices usually use capillary action to manipulate liquids, which requires micron-level precision and is difficult to operate. According to the technical solution of this embodiment, micron-level precision is not required, but the operation of fluid movement is achieved through a moving surface.

Example 9

In one embodiment, a shear-driven fluid platform as shown in FIG. 17 is constructed, wherein the first fluid 906 can be subjected to shear flow by energy applied based on force, heat, light, electrical effects, etc.

The shear-driven fluid platform device can be in the form of Figure 17. In the above embodiments, there are always two walls in relative motion, but this is not a necessary condition. The wall can also be static, and the liquid is sheared by the mechanism of force, heat, light, and electricity. These solutions can make the system smaller and more intelligent, and do not require a control device for wall movement, so as to achieve the purpose of saving reagents and rapid reaction.

In the first method of driving flow, by setting a thermocouple on the wall, hot bubbles can be quickly generated. Hot bubbles are generated and/or transmitted from one end to the other, pushing the liquid in the thin flow field in the form of shear. The liquid passes through pipe A with a one-way valve, pushing the original liquid to the waste liquid pool. The liquid cools, the bubbles disappear, and the liquid flows back into the flow field through pipe B with a one-way valve to achieve liquid replacement. Pipes A and B can belong to the two ends of the surface and contain different liquids. Bubbles can also be input externally, such as an external air pipe.

Specifically, as shown in FIG. 17( a ), a thermocouple 921 is provided on the first wall 901, which can quickly generate hot bubbles 922. The hot bubbles 922 are generated and transmitted from one end to the other end, pushing the liquid in the thin flow area 903 in the form of shear. The liquid is pushed away from the flow area 903 through the outlet pipe 931 with a one-way valve. After cooling, the bubbles 922 disappear, and the liquid flows back into the flow area through the inlet pipe 932 with a one-way valve, thereby achieving liquid replacement.

Similarly, in the second method of driving flow, by forming a magnetic field on the wall, the movement of the magnetic field can quickly push the elliptical magnetic fluid to form in the flow field, and the magnetic fluid then pushes the liquid to form shear flow. The liquid passes through the pipeline A with a one-way valve, pushing the original liquid to the waste liquid pool. At the same time, the new liquid flows into the flow field through the pipeline B with a one-way valve. The magnetic field disappears or changes, and the magnetic fluid flows back in a dispersed form and proceeds to the next cycle.

Specifically, as shown in FIG17( b), a moving magnet 923 is provided on the first wall 901. The movement of the magnet 923 can quickly push the magnetic fluid 924 to form in the flow area 903, and the magnetic fluid 924 pushes the liquid to form shear flow. The original first fluid 906 is pushed away from the flow area 903 through the outlet pipe 931 with a one-way valve. At the same time, the new liquid flows into the flow area 903 through the inlet pipe 932 with a one-way valve to achieve liquid replacement.

Similarly, in the third method of driving flow, green light passes through the pipe wall and solidifies naphthalene and the coupling molecule triazole dione. The solidification process can promote shear flow in the flow area. The liquid passes through the pipe A with a one-way valve, pushing the original liquid to the waste liquid pool. At the same time, new liquid flows into the flow area through the pipe B with a one-way valve. The green light disappears, and the naphthalene and the coupling molecule triazole dione become soft and liquefied, which is convenient for the next cycle.

Specifically, as shown in FIG. 17( c ), the green light 925 passes through the tube wall and solidifies the naphthalene and the coupling molecule triazole dione 926, and the solidification process promotes shear flow in the flow field 903. The liquid passes through the outlet pipe 931 with a one-way valve, pushing the original liquid away from the flow field 903. At the same time, the new liquid flows into the flow field 903 through the inlet pipe 932 with a one-way valve. When the green light 925 disappears, the naphthalene and the coupling molecule triazole dione 926 become soft and liquefied again.

Similarly, in the fourth method of driving flow, the immiscible liquid in the flow domain or the miscible liquid separated by bubbles is transported through the principle of electrowetting, and the movement of the liquid promotes the shear flow in the flow domain. The liquid passes through pipeline A with a one-way valve, pushing the original liquid to the waste liquid pool. At the same time, the new liquid flows into the flow domain through pipeline B with a one-way valve. When the voltage is removed, the heterogeneous liquid flows back in a non-plunger form, facilitating the next cycle. For gas, it can be released outside the flow domain, for example, through bypass and liquid logic control, and new separation bubbles are introduced.

Specifically, as shown in FIG17( d ), the movement of the heterogeneous liquid or gas 927 in the flow field 903 is driven by electrowetting to form a shear flow in the flow field 903. The liquid passes through the outlet pipe 931 with a one-way valve, pushing the original liquid away from the flow field 903. At the same time, new liquid flows into the flow field 903 through the inlet pipe 932 with a one-way valve.

Example 10

In one embodiment, a shear-driven fluid platform as shown in FIG. 18 is constructed, wherein the height of the first wall 1001 is higher than the second wall 1002 , and the first wall 1001 moves axially relative to the second wall 1002 .

The shear-driven fluid platform device can be in the form of Figure 18. Here, the shear flow direction of the quattrotype is changed to the first wall 1001 moving up and down for shearing. Obviously, when moving upward, the fluid in the reactor is sucked in, and when moving downward, the fluid is squeezed out. Because both are not absolutely smooth, when the conditions of the aforementioned embodiment 6 are met and the flow domain is not filled with liquid, the liquid at the edge of the flow domain will also be sucked in.

Taking the use of the device to replace Roche's Cobas Liat system for nucleic acid determination as an example, the specific implementation scheme is that the second wall 1002 is a plane made of hydrophobic glass, and the first wall 1001 is a cylindrical material made of aluminum. The aluminum cylinder is placed on the hydrophobic glass. All movements are controlled by the control mechanism 1012. First, add the sample, drop a buffer solution containing oral epithelial cells in the matching dropper on the second wall 1002, move the first wall 1001 to the edge of the sample to contact the sample, and the sample is sucked into the flow basin. The sample preparation procedure is skipped here. Then, similarly, drop the initialization area containing PBS buffer and proteinase K premix, and the liquid is sucked into the flow basin. Then, the first wall 1001 moves up and down several times to mix the sample. Because of the power of the liquid itself, although there is no gasket, the distance between the aluminum cylinder and the glass is still about 50 microns. At this time, the first wall 1001 is heated to 40 degrees by the heater and stays for one minute. Next, the lysis solution is added dropwise, and the first wall 1001 is moved up and down several times, and then heated and maintained at 50 degrees for incubation for 5 minutes. Next, the isopropanol magnetic bead suspension is added dropwise, and the first wall 1001 is moved up and down several times and then stays for 5 minutes. Next, the control mechanism 1012 controls the magnetic rack 1009 to approach, and the magnetic beads are attracted. After 1 minute, a large amount of cleaning solution is added dropwise, and the first wall 1001 is moved up and down 20 times to wash the magnetic beads. After that, the first wall 1001 is in close contact with the second wall 1002. Tilt at 45 degrees to allow excess cleaning solution to drain. Add 50 microliters of cleaning solution, move the first wall 1001 up, and the eluent enters the basin. After moving up and down several times, the control mechanism 1012 removes the magnetic rack 1009. Add UNG enzyme, and the first wall 1001 is moved up and down several times and then maintained at 37°C for 5 minutes to digest the PCR contaminated products. The first wall 1001 is heated to the 95°C zone to inactivate the UNG enzyme and denature the DNA. The first wall 1001 is cooled to 60° C. for amplification. This process is repeated, and after each cycle (or after multiple consecutive cycles), a picture is taken to determine the fluorescence intensity by analyzing the average grayscale of the picture.

In an optional embodiment, as shown in FIG19 , the inlet 1004 includes a channel provided on the second wall 102 for introducing fluid into the flow field. Different components in the first fluid 1006 are contained in a plurality of containers, and the rotary valve 1015 introduces the first fluid 1006 of different components into between the first wall 1001 and the second wall 1002 through the inlet 1004 .

In addition, the device can be used for other biochemical reactions to achieve different purposes. In addition, the device can use common medical device automation solutions, such as stepper motors or pneumatic control of the movement of the first wall 1001. In addition, a limit device can be added to control the movement distance of the first wall 1001. In addition, a ventilation device can be added for drying. If the droplet device performs automated sampling. Compared with traditional microfluidic devices such as Cobas Liat, the stability of this case is greatly improved, reducing the problem of false positive results due to unreliable packaging of Cobas Liat. At the same time, it has a simple structure, low cost, fast reaction speed, and uses less reagents.

Embodiment 11

In one embodiment, a shear-driven fluid platform as shown in FIG. 20 is constructed, and a Couette-like flow is applied to two surfaces that are close to each other and move relative to each other, one of which is a plane and the other is a curved surface, to save the amount of reagent consumed in the process. The shear-driven fluid platform is shown in FIG. 20, and it can be seen that one of its two sleeves, such as the inner sleeve, is in the form of a multi-prism, such as a hexagonal prism shown in FIG. 20. The purpose and timing are similar to the sleeve of Example 2, and can be used for PCR, DNA sequencing, chip cleaning, etc.

In an optional embodiment, the inner cylinder is in the form of a cylinder, and the outer cylinder is in the form of a polygonal column.

Specifically, referring to Fig. 20, the first wall 1101 rotates and the second wall 1102 remains fixed. The first fluid 1106 enters the flow domain between the first wall 1101 and the second wall 1102 from the inlet 1104 and leaves the flow domain from the outlet 1105. Vice versa.

In an optional embodiment, the process of cleaning a chip using a shear-driven fluid platform comprises the following steps:

1. Insert six chips into the slot to form a second wall surface 1102 with a hexagonal cross-section close to the first wall surface 1101.

2. The first fluid 1106 is added to the opening of the first wall 1101 and fills the thin flow region 1103 until the space between the first wall 1101 and the second wall 1102 is filled with liquid. The first liquid 1106 can be pure water, IPA, or Acetone.

3. The first wall 1101 starts to rotate and axially reciprocate, while the first fluid 1106 is continuously added, and the first fluid 1106 continuously flows out from the outlet 1105 of the second wall.

4. As the first wall 1101 rotates, the first fluid 1106 moves. Where the first wall 1101 and the second wall 1102 are close, the liquid approaches laminar flow. As the cross section increases, the liquid transitions to turbulent flow and may form a vortex.

5. Add high-pressure gas and/or surfactant to clean the second wall surface 1102 together.

6. The first wall 1101 descends to expose the chip surface, and the surface is dried with high-pressure air.

7. Remove the chip.

Example 12

In one embodiment, a shear-driven fluid platform as shown in FIG. 21 is constructed.

Specifically, referring to FIG. 21 , the first wall 1201 is connected to the rotating mechanism 1273 through a fixed position 1272, a rotating filling head 1271 is provided on the gantry 1274, and the first fluid 1206 flows out of the rotating filling head 1271 and enters the flow field 1203 through the inlet 1204 on the first wall 1201. The second wall 1202 is fixed on the gantry 1274 and remains stationary, and the first wall rotates under the drive of the rotating mechanism 1273, so that the first fluid 1206 traverses the entire second wall 1202.

By using the shear-driven fluid platform of this embodiment, the fluid in the liquid path structure can have a lower thickness and, at the same time, can cause the reagent to produce a more efficient reaction through the shear flow field.

It can be known from the description of the above implementation mode that those skilled in the art can clearly understand that all or part of the steps in the above-mentioned embodiment method can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product can be stored in a storage medium such as ROM/RAM, a disk, an optical disk, etc., including several instructions for enabling a computer device (which can be a personal computer, a server, or a network communication device such as a media gateway, etc.) to execute the methods described in the various embodiments of the present application or certain parts of the embodiments.

It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other. For the method disclosed in the embodiment, since it corresponds to the system disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the system part description.

It should also be noted that, in this article, the term "comprises", "includes" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

The above description of the disclosed embodiments will enable professionals in the field to implement or use the various modifications of these embodiments to be apparent to professionals in the field, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

This application further includes the following examples:

A method of designing a flow basin that contains multiple walls, inlets, outlets, and sides of the flow basin.

1) Multiple walls are close to or in contact with each other, and the space facing each other forms a flow basin.

2) The watershed contains at least one thin watershed.

3) There is viscous fluid in the flow domain, which is driven by shear force.

4) According to the direction of the average flow velocity, a fluid inlet and an outlet are formed.

In some possible embodiments, the height of at least a portion of the area of the thin flow basin is one order of magnitude smaller than the length or width, and the height is preferably sub-millimeter level.

In some possible embodiments, the inlet is a free surface, or the fluid connected to the inlet has at least one free surface. The outlet is a free surface, or the fluid connected to the outlet has at least one free surface.

In some possible embodiments, the sides of the flow area are not sealed between the walls, and the fluid overflows.

In some possible embodiments, the static pressure of the fluid connected to the inlet and outlet is equivalent to that of the external environment, or the pressure is no more than 1/5 of the pressure required for pure pressure drive under the same flow conditions (speed, spacing, length, liquid type, etc.), or/and has a constant speed.

In some possible embodiments, at the inlet, different types of fluids are not mixed before reaching the vicinity of the inlet area.

In some possible embodiments, at the inlet, an excess of fluid connected to the flow field can be seen.

In some possible embodiments, in the flow basin, the energy that can be provided by the fluid pressure difference between the inlet and the outlet of the flow basin is less than half of the energy consumed by the fluid flowing in the flow basin.

In some possible embodiments, the flow rate of the fluid entering the flow basin from the inlet is greater than or equal to the product of the smallest cross-sectional area in the direction of the average flow velocity in the flow basin and the average flow velocity at the inlet. The flow rate flowing out from the outlet is less than or equal to the product of the largest cross-sectional area in the flow basin and the average flow velocity at the outlet.

In some possible embodiments, the shape of the flow domain includes at least one thin-sheet flow domain.

In some possible embodiments, the thin flow area is in a laminar flow state except for the edge of the flow area and discontinuous places (such as places where the height is 0).

In some possible embodiments, the thin-sheet flow basin has unique upper and lower walls that are parallel to each other, or the formed inclination angle is no greater than 30 degrees.

In some possible embodiments, the upper and lower walls of the thin-sheet flow basin are curved surfaces, and the tangent lines or tangent planes at two opposite points are parallel, or the formed inclination angle is not greater than 30 degrees. In special cases, the thin-sheet flow basin is two concentric cylinders.

In some possible embodiments, the direction of movement of each point on the wall of the flow domain that constitutes the thin flow domain is the tangent direction of the point on the wall. Therefore, when the wall moves, its shape coincides with its shape at the previous moment. In special cases, the wall is a plane (translation), a cylinder or a disk (rotation).

In some possible embodiments, the flow domain, the direction of movement of each point on the wall constituting the thin-sheet channel, is consistent with the direction of movement of the liquid in the fluid channel. When the wall moves, it is parallel to its shape at the last moment.

In some possible embodiments, the design of the walls of at least part of the area on the upper and lower sides of the flow domain is matched with the liquid properties or flow process, so that the liquid can be confined in the thin sheet flow domain without side walls. Preferably, the sum of the cosine values of the contact angles of the upper wall and the lower wall opposite to the fluid on at least part of the flow domain area is greater than or equal to 0.

In some possible embodiments, at least a portion of the area does not match the liquid property or flow process, making it difficult for the liquid to overflow across this portion of the area. Preferably, for at least a portion of the flow area, the sum of the cosine values of the contact angles of the upper wall and the lower wall opposite thereto with the fluid is less than or equal to 0.

In some possible embodiments, in actual operation, the liquid in the flow area may exceed the designed sheet flow area and overflow, and the overflowed liquid can be carried away by the shear force.

In some possible embodiments, the wall of the moving sheet channel, at least in part, is a flexible but non-stretchable membrane.

In some possible embodiments, the flow field wall is a liquid wall or a gas wall formed by immiscible liquid or gas.

In some possible embodiments, the flow field and shear force are formed by the liquid in the thin sheet being driven by physical methods such as force, heat, light, electricity, and magnetism, such as electrowetting, acoustic energy drive, bubble drive, photodeformation, and magnetic fluid.

In some possible embodiments, in the flow field, the distance between at least some points of the upper and lower surfaces of the thin-sheet channel is 0. In this case, the liquid flows through the gaps between natural microscopic non-smooth surfaces or the gaps between artificially prepared non-smooth surfaces.

In some possible embodiments, the flow field can form a stable or substantially stable flow field within one minute.

In some possible embodiments, in the viscous flow field, a substance for viscosity adjustment, preferably glycerol, is added to the fluid, and/or a surfactant, preferably Tween, is added.

According to the above-mentioned method for constructing a Couette-like flow field, the present application also provides a method for using a hardware platform related to the construction method, and the method for using includes:

The fluid is filled into the inlet of the flow field, and the fluid is connected with the flow domain and fills at least the thin flow domain.

If necessary, fill the flow field with auxiliary fluid.

If necessary, open the auxiliary outflow mechanism and/or fluid outlet device of the outlet.

Apply shear forces to the system.

The hardware platform for constructing a Couette-like flow field is called a shear-driven fluid platform, and includes:

The solid wall is in contact with the fluid and plays a role in constraining the fluid, and the fluid contains the fluid wall. The space between the walls is the flow domain.

The inlet can be the inlet of the flow field, where the free surface of the fluid is visible; or it can be a shape that has a liquid retention function and is connected to the liquid in the flow field, such as a pipe or a funnel. The surface properties of the device can prevent liquid adhesion. Before reaching the inlet area, different fluids are physically isolated from each other. After reaching the inlet area, the fluids are affected by shear forces.

The driving device includes at least one energy conversion method that can generate shear force on the liquid in the flow area, so that the fluid speed close to a wall is faster than the fluid speed close to other walls. The driving device includes an energy supply device, which can be manpower or power supply.

The flow domain contains material that interacts with the material in the fluid, which can be the solid wall itself or a material fixed to the solid wall. It can be stored in a storage chamber that the liquid will contact, or added from an inlet.

When shear force is applied, at least the thin areas in the basin are filled.

In some possible embodiments, the driving device and the wall include:

The moving tensioned membrane serves as the moving wall. The electric energy system is used as the energy supply device, including a reducer, a motor, and a power supply.

In some possible embodiments, a bypass device is also included;

The bypass device is used to discharge excess liquid from the basin to prevent the entire mechanism from being contaminated or liquid accumulation.

In some possible embodiments, the positioning device includes: a mechanical device that fixes the relative position of the moving wall to other walls but weakly constrains the moving direction. In particular, if the moving wall is a liquid wall, the device can be a solid container.

In some possible embodiments, the liquid circuit system, the positioning device further includes a gap locking mechanism;

The gap locking mechanism includes a gap enlarging mechanism and a gap reducing mechanism. The gap locking mechanism is connected to different walls, the gap reducing mechanism controls the distance between different walls to prevent further distance, and the gap enlarging mechanism adjusts the distance between the walls to prevent further approach.

In some possible embodiments, a fluid introduction device is further included;

The fluid introduction device is used to add fluid to the inlet of the flow field. The fluid introduction device may have a certain anti-pollution function or be disposable. The fluid introduction device may be other microfluidic chips or microfluidic structures.

In some possible embodiments, the fluid introduction device includes at least one of coating, transfer, coating (or spraying, printing), mutual exclusion, coating, inkjet, pipette, hollow fiber catheter or guidewire.

In some possible embodiments, a temperature control device is further included;

The temperature control device is used to control the temperature of the reaction.

Furthermore, more than one temperature control device is included to control the temperature of different areas of the basin respectively.

Further, the inlet adds fluid to more than one temperature zone in the flow domain, respectively.

In some possible embodiments, a detection device is further included;

The detection device is used to detect post-reaction indicators, such as fluorescence, color development, gas production, luminescence, changes in the concentration of at least one product, etc., and/or the absence of a reaction.

In some possible embodiments, a control unit is also included;

The control unit is respectively connected to the signals of the electrical components in the hardware platform to control the electrical components and/or read or transmit relevant signals/instructions.

The present application also provides a method for using a shear-driven fluid platform, the method comprising:

Add fluid to the inlet of the hardware platform;

When the drive is turned on, shear forces cause the fluid near one wall to flow faster than the fluid near the other walls.

The fluid fills at least the thin flow area in the flow domain.

When necessary, different types of fluids are added to the inlet, and the different types of fluids do not mix before reaching the inlet area.

When necessary, stop adding fluid to the inlet and pause the drive unit.

The present application also provides a microfluidic chip system, comprising any one of the flow field construction methods described above or any one of the hardware platforms described above.

Various types of microfluidic chips are currently widely used, such as blood gas chips, sequencing flow pools, and in vitro diagnostic markers (such as myocardial markers) detection chips. The fluid is introduced into a thinner pipe or a thinner flow basin, and then the fluid reacts in the chip to perform various index detection, chemical synthesis, gene detection, PCR, separation, mixing, droplet formation, active substance cultivation, etc. In this process, the reactants may exist in the chip, such as freeze-dried powder being carried away by the fluid or fixed somewhere on the chip. However, the current mainstream method of using pressure to drive the fluid is more advantageous in laboratory scenarios, and in reality, requiring all testers to use pumps to intervene in the chip increases the requirements for users. At the same time, the external equipment needs to be continuously sampled, and the external equipment is considerable in size, which also increases the difficulty of deploying the microfluidic system and the insufficient saving of reagents. Especially in some cases containing enzymes, bases, precious samples or fluids, reagents often become the largest cost. The microfluidic chip is very small in size, but the attached equipment is large in size, which also makes the entire system lose the advantage of portability.

In order to solve the above technical problems, the present application provides a pressure-independent Couette-like flow field construction method and a shear fluid hardware platform. Specifically, the liquid path includes a first surface and a second surface.

The first surface at least includes an exposed chip surface. Specifically, the exposed chip surface refers to the surface of the chip to be sequenced that is loaded with a DNB (DNA nanoball) library and is used for reaction.

It should be noted that the exposed chip surface may also be the surface of the chip to be sequenced that is loaded with other substances.

It should also be noted that the first surface may be a completely exposed chip surface, or may include, in addition to the exposed chip surface, a circumferential protective surface for protecting the chip surface that is arranged at a position that does not participate in the reaction.

A reagent liquid is disposed at a preset position of the second surface, and the reagent liquid can move along with the movement of the second surface.

The second surface can move in a preset direction and drive the reagent solution at a preset position to at least be injected into the gap between the chip surface and the second surface. In the present application, the reagent solution is injected into at least the gap between the chip surface and the second surface so that the reagent solution can at least flow through the chip surface to complete sequencing.

It should be noted that the reagent liquid at the preset position of the second surface can be coated at the preset position by a liquid loading device. The types of the reagent liquids coated are sequentially loaded to the preset position according to the reaction sequence, and each reagent liquid can be cleaned and replaced by the next reagent liquid entering the liquid path through the movement of the second surface.

Please refer to the fact that the first surface can be located above the second surface or below the second surface. The drawings provided in the embodiments of the present application and any description of the first and second are only for the purpose of introducing exemplary positions, and the embodiments of the present application are not limited here. The reagent solution in the gap between the first surface and the second surface is used to detect the gene sequence. Specifically, the reagent solution contacts and reacts with the exposed chip surface to realize the recognition of the base sequence in the gene.

In the gene sequencing process, the reagent solution flows through different positions of the chip surface as the second surface moves to react. As an example, the sequencing process may need to replace multiple reagent solutions in the gap to achieve up to 200 "reaction-photographing" cycles. In the embodiment of the present application, a reagent solution is applied to the preset position of the second surface, and then the second surface moves in the preset direction V, so that the reagent solution at the preset position is injected into the gap between the first surface and the second surface, i.e., the gap. At the same time, the second surface originally located above the first surface moves out of the first surface, so that the reagent solution in the gap attached to the second surface is extracted from the gap as the second surface moves. With the continuous injection of the new reagent solution at the preset position and the continuous extraction of the original reagent solution in the gap, the reagent solution in the gap is gradually replaced by the new reagent solution to complete the cleaning and filling of the liquid path, thereby realizing the displacement of the reagent solution contacted by the sequencing chip. For ease of expression, the original reagent solution is named the first reagent solution, and the new reagent solution is named the second reagent solution.

In the embodiment of the present application, when the first reagent liquid in the gap between the first surface and the second surface is completely displaced by the second reagent liquid, the first reagent liquid has reacted, and the reaction result has been photographed and recorded. At this time, other reagent liquids can be provided, the second surface continues to move, and the second reagent liquid will replace the first reagent liquid in the gap between the first surface and the second surface, thus achieving multiple "reaction-photographing" cycles and obtaining multiple gene sequencing results.

In order to ensure that the gap between the first surface and the second surface is filled with reagent liquid, the gap height between the first surface and the second surface is less than or equal to twice the thickness of the reagent liquid at the preset position. It should be noted that, during the movement of the second surface, the flow rate entering the gap is the moving speed of the second surface multiplied by the liquid thickness and liquid width at the preset position on the first surface. Since the first surface is stationary, the average flow rate of the reagent liquid in the gap is half of the moving speed of the second surface, therefore, the flow rate of the reagent liquid in the gap is the moving speed of the second surface multiplied by the gap height and the reagent liquid width. Therefore, in order to make the flow rate of the reagent liquid 05 in the gap less than or equal to the liquid inlet flow rate, that is, the gap between the first surface and the second surface is filled with reagent liquid, the gap height between the first surface and the second surface is less than or equal to twice the thickness of the reagent liquid at the preset position.

In the embodiment of the present application, the hydrophilicity of the first surface and the second surface meets the requirements of the reagent solution entering the gap, the cosine value of the contact angle between the first surface and the reagent solution is greater than 0, and the cosine value of the contact angle between the second surface and the reagent solution is greater than 0.

It can be known from the description of the above implementation mode that those skilled in the art can clearly understand that all or part of the steps in the above-mentioned embodiment method can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product can be stored in a storage medium such as ROM/RAM, a disk, an optical disk, etc., including several instructions for enabling a computer device (which can be a personal computer, a server, or a network communication device such as a media gateway, etc.) to execute the methods described in the various embodiments of the present application or certain parts of the embodiments.

The present invention also discloses the following technical solutions:

In order to solve the above-mentioned problems of microfluidic technology, the present application provides a technology, which includes a Couette-like flow field construction method, a construction device and an application in the field of microfluidics. Considering a product is usually divided into several main aspects such as reliability, performance, and cost. Traditional biochemical electromechanical equipment usually uses macroscopic amounts of fluid when it comes to fluids. For example, medical equipment uses a whole tube of reagents to detect a sample, or the chip is directly connected to pure water with a water pipe to rinse the surface and the chip is soaked in the chemical reagents of the entire pool to react and clean, which causes two problems: 1. The cost is expensive and a large amount of reagents are required; 2. The performance may be low because the mass transfer in bulk liquids is always slow. Microfluidic technology confines the reaction to a chip because the channel is micron-scale, consumes less reagents, has fast mass transfer, and reacts quickly. However, traditional microfluidic technology requires the construction of a three-dimensional liquid channel to constrain the flow of the liquid. The height and width of the channel are both microscopic scales, and the flow direction is macroscopic scales. In order to provide energy to offset the friction of the liquid moving in the microchannel, it is usually necessary to encapsulate the entire system and use a pump-type fluid device to continuously provide pressure to push the fluid and prevent leakage. This makes the system have many components, and the pipeline is difficult to clean, resulting in an increase in reagent consumption. There are also passive methods such as capillary force, but this method is more difficult to control and is usually used in simpler detection. Therefore, microfluidic devices 1 save reagents, but the chip cost is high; 2 R&D and production are difficult, and have not yet been widely popularized; 3 The pipeline connecting the chip is macroscopic, and this part of the reagent consumption is large. There is now a technology of "open microfluidics", but it is mainly to remove the upper cover plate from the microchannel, and at the same time, the channel is treated by hydrophilic and hydrophobic modification, so that the liquid can flow along the microchannel without the upper cover. Although this method makes manufacturing simpler, it still cannot completely get rid of the problems of the above-mentioned traditional microfluidic devices, and it is difficult to actively control, and it can usually only be used in simple usage scenarios. The technology of the present invention draws on the advantages of traditional biochemical electromechanical equipment and microfluidic equipment, achieves the effects of saving reagents, rapid response, stable and reliable, and abandons the shortcomings of both, so that it is expected to replace the two.

Method for constructing Couette-like flow field

In order to solve at least one of the above problems and/or other potential problems of the prior art, it is necessary to invent a new fluid driving method and its hardware platform. Our technology is called the Couette-like flow field construction method, and the related hardware platform is called the shear-driven fluid platform. It mainly uses the shear force of the fluid to construct a flow field similar to the Couette flow field, which is used to replace the traditional method-the Poisson leaf flow field that uses pure pressure drive to overcome the friction between the fluid and the solid wall surface that constitutes the thin flow domain. The purpose of this design is first to use a small amount of fluid to achieve rapid surface cleaning and replace the liquid originally existing in the flow domain, saving costs. Secondly, there are fewer parts involved, eliminating complex seals and pipeline valves, and increasing reliability. Third, the quality control of the device becomes simpler because the number of parts is greatly reduced. Fourth, operation and development become simple and low-cost because no packaging or fluid knowledge background is required.

To construct a Couette-like flow field, the present application first provides a liquid path structure, including

The first wall,

The second wall surface is configured to be disposed close to or at least partially in contact with the first wall surface, and the space facing each other forms a flow basin, and the flow basin includes a thin flow basin;

an inlet structure configured to include one or more inlets, which are in communication with the flow basin when in operation, so that a fluid including at least a first fluid can be introduced into the flow basin; wherein the fluid of the first fluid can be directly introduced into the flow basin without passing through a common pipeline;

An outlet structure is configured to include one or more outlets and is in communication with the flow basin during operation so that the fluid passing through the flow basin is discharged;

Wherein, during operation, the first fluid is configured to be able to be applied with energy, and the energy can be converted into fluid kinetic energy, thereby forming a shear flow of the first fluid in the flow domain.

Optionally, during operation, the first wall surface is configured to be able to move relative to the second wall surface, thereby applying energy to the first fluid to drive the shear flow of the first fluid.

Optionally, the first wall and the second wall include substantially parallel planes, preferably with an angle of no more than 30 degrees;

Optionally, the movement of the first wall includes a translation substantially parallel to the second wall, a translation in a direction approaching or moving away from the second wall, and a rotation relative to the second wall.

Optionally, the first wall surface includes a bendable film material.

Optionally, the first fluid is configured to be capable of shear flow when energy is applied thereto based on one of force, heat, light, and electrical effects.

Optionally, the inlet structure includes a first inlet and a second inlet,

wherein the first fluid flows from the first inlet through the flow field and flows out from an outlet of the outlet structure,

The second fluid flows into the flow domain from the second inlet and flows out from one outlet of the outlet structure, sharing an outlet with the first fluid, or flows out from another outlet of the outlet structure, using different outlets with the first fluid, wherein the second fluid and the first fluid are laminar flows in the thin flow domain, and the second fluid occupies a certain space in the thin flow domain so that the required amount of the first fluid is further reduced.

Optionally, the second fluid contacts the first fluid in the thin region, and its flow region does not overlap with the first fluid.

Optionally, the fluid is introduced in a temporally or spatially discrete manner through an inlet structure, including:

The inlet structure includes an inlet, into which the first fluids are introduced at different times, or when the first fluids are introduced at the same time, an incompatible fluid is used to separate the first fluids, so that the first fluids will not mix with each other before entering the thin flow area; or

The inlet structure includes a plurality of inlets, and each first fluid is introduced through a different inlet, so that each first fluid will not mix with each other before entering the thin flow area.

Optionally, the inlet structure further includes a liquid storage structure for storing a predetermined amount of the first fluid to ensure that a sufficient amount of the first fluid fills the flow basin through the inlet and prevents air from being brought in; wherein the predetermined amount is slightly larger than the fluid capacity required by the flow basin.

Optionally, the first wall surface and the second wall surface include curved surfaces to form a sleeve shape, wherein one of the first wall surface and the second wall surface forms an outer cylinder, and the other forms an inner cylinder, and a flow domain is formed between the two.

Optionally, the outlet structure is configured to enable the fluid from the thin flow area to be discharged freely and unobstructed to avoid blockage affecting the fluid introduction inlet.

Optionally, the materials of the first wall and the second wall are selected such that their hydrophilicity and hydrophobicity enable the first fluid to be located between the first wall and the second wall in a free state without being expelled by surface tension.

Optionally, the material of the second wall is selected such that it has poor affinity with the first fluid in the flow domain, so that the first fluid flowing out of the flow domain by shear motion will be sucked back into the flow domain.

Optionally, the sum of cosine values of contact angles of the first wall and the second wall with the first fluid is greater than or equal to zero.

Optionally, the inlet includes a free surface, or the fluid connected to the inlet has at least one free surface; the outlet includes a free surface, or the fluid connected to the outlet has at least one free surface.

Optionally, the thick dimension of the thin watershed is an order of magnitude smaller than the long and/or wide dimensions of the thin watershed.

Optionally, there is a velocity gradient for the first fluid between the first wall and the second wall, and the first fluid has a faster flow rate on the side affected by energy or with less resistance.

Optionally, the first fluid includes a liquid, specifically a medicine.

Optionally, the thickness scale is sub-millimeter.

The operating method of the aforementioned liquid circuit structure comprises:

providing a first wall surface,

Providing a second wall surface, which is configured to be disposed close to or at least partially in contact with the first wall surface, and the space facing the second wall surface forms a flow domain, and the flow domain includes a thin flow domain;

Providing an inlet structure, configured to include one or more inlets, which are in operative communication with the flow basin, so that a fluid including at least a first fluid can be introduced into the flow basin; wherein the fluid of the first fluid can be directly introduced into the flow basin without passing through a common pipeline;

Providing an outlet structure, which is configured to include one or more outlets and is in communication with the flow basin during operation so that the fluid passing through the flow basin is discharged;

Wherein, during operation, the first fluid is configured to be able to be applied with energy, and the energy can be converted into fluid kinetic energy, thereby forming a shear flow of the first fluid in the flow domain.

Optionally, during operation, the first wall surface is configured to be able to move relative to the second wall surface, thereby applying energy to the first fluid to drive the shear flow of the first fluid.

Optionally, the first wall and the second wall include substantially parallel planes, preferably with an angle of no more than 30 degrees;

Optionally, the movement of the first wall includes a translation substantially parallel to the second wall, a translation in a direction approaching or moving away from the second wall, and a rotation relative to the second wall.

Optionally, the first wall surface includes a bendable film material.

Optionally, the first fluid is configured to be capable of shear flow when energy is applied thereto based on one of force, heat, light, and electrical effects.

Optionally, the inlet structure includes a first inlet and a second inlet,

wherein the first fluid flows from the first inlet through the flow field and flows out from an outlet of the outlet structure,

The second fluid flows into the flow field from the second inlet and flows out from an outlet of the outlet structure, and the first fluid and the second fluid share one outlet, or flows out from another outlet of the outlet structure, and the first fluid and the second fluid use different outlets respectively.

The second fluid and the first fluid are laminar flows in the thin flow area, and the second fluid occupies a certain space in the thin flow area so that the required amount of the first fluid is further reduced.

Optionally, the second fluid contacts the first fluid in the thin region, and its flow region does not overlap with the first fluid.

Optionally, the fluid is introduced in a temporally or spatially discrete manner through an inlet structure, including:

The inlet structure includes an inlet, into which the first fluids are introduced at different times, or when the first fluids are introduced at the same time, an incompatible fluid is used to separate the first fluids, so that the first fluids will not mix with each other before entering the thin flow area; or

The inlet structure includes a plurality of inlets, and each first fluid is introduced through a different inlet, so that each first fluid will not mix with each other before entering the thin flow area.

Optionally, the inlet structure further includes a liquid storage structure for storing a predetermined amount of the first fluid to ensure that a sufficient amount of the first fluid fills the flow basin through the inlet and prevents air from being brought in; wherein the predetermined amount is slightly larger than the fluid capacity required by the flow basin.

Optionally, the first wall surface and the second wall surface include curved surfaces to form a sleeve shape, wherein one of the first wall surface and the second wall surface forms an outer cylinder, and the other forms an inner cylinder, and a flow domain is formed between the two.

Optionally, the outlet structure is configured to enable the fluid from the thin flow area to be discharged freely and unobstructed to avoid blockage affecting the fluid introduction inlet.

Optionally, the materials of the first wall and the second wall are selected such that their hydrophilicity and hydrophobicity enable the first fluid to be located between the first wall and the second wall in a free state without being expelled by surface tension.

Optionally, the material of the second wall is selected such that it has poor affinity with the first fluid in the flow domain, so that the first fluid flowing out of the flow domain by shear motion will be sucked back into the flow domain.

Optionally, the sum of cosine values of contact angles of the first wall and the second wall with the first fluid is greater than or equal to zero.

Optionally, the inlet includes a free surface, or the fluid connected to the inlet has at least one free surface; the outlet includes a free surface, or the fluid connected to the outlet has at least one free surface.

Optionally, the thick dimension of the thin watershed is an order of magnitude smaller than the long and/or wide dimensions of the thin watershed.

Optionally, there is a velocity gradient for the first fluid between the first wall and the second wall, and the first fluid has a faster flow rate on the side affected by energy or with less resistance.

Optionally, the first fluid includes a liquid, specifically a medicine.

Optionally, the thickness scale is sub-millimeter.

The Couette-like flow field construction method provided in the present application injects the fluid into the inlet and starts the shear force driving device, so that the fluid is injected into at least the thin area in the flow domain, so that the interaction occurs. In the present application, since the pressure drive or surface tension drive of the traditional microfluidic platform is replaced by shear force drive, on the one hand, the improvement of energy input and performance optimization are more convenient, and there is no problem of pressure over limit; in addition, the structure is simple, avoiding the learning and use obstacles caused by a large number of external equipment; thirdly, a large number of external pipelines are eliminated, saving cleaning time and cost. Fourth, sealing is not required, avoiding the cost and inconsistency of packaging.

Therefore, this application overcomes the problems of high cost, difficulty in using, and low performance of traditional microfluidic devices, making its market penetration prospect more prominent.

In addition, this application also includes a supplement recording the following technical solutions:

1. A method for designing a watershed, characterized by comprising a plurality of walls, an inlet, an outlet and a side of the watershed.

The multiple walls are close to or in contact with each other, and the space facing each other forms a flow domain, and the flow domain includes at least one thin flow domain.

There is a viscous fluid in the thin flow domain, which moves under the drive of shear force. The fluid in contact with at least one wall moves faster than the fluid in contact with other walls.

According to the direction of the average flow velocity, the fluid inlet and outlet are formed. The energy provided by the pressure difference between the inlet and the outlet is less than the energy required for the fluid to flow through a channel composed of solid walls under the same conditions.

2. The thin basin is characterized in that the height of at least part of the basin area is one order of magnitude smaller than the length or width, and the height is preferably sub-millimeter level.

3. The inlet is characterized in that the inlet is a free surface or a fluid connected to the inlet has at least one free surface. The outlet is a free surface or a fluid connected to the outlet has at least one free surface.

4. The inlet and outlet are characterized in that the static pressure of the fluid connected thereto is equal to or close to that of the external environment.

5. The inlet and outlet are characterized in that the fluid connected thereto has a constant pressure or velocity.

6. The side of the flow basin is characterized in that there is no encapsulation between the walls, and the fluid overflows.

7. The inlet is characterized in that an excess of fluid connected to the flow basin is visible.

8. The described flow basin is characterized in that the energy provided by the fluid pressure difference between the inlet and outlet of the flow basin is less than 2/3 of the energy consumed by the fluid flowing in a flow basin of the same size under the same conditions without the existence of shear force.

9. The flow basin is characterized in that the flow rate of the fluid entering the flow basin from the inlet is greater than or equal to the product of the smallest cross-sectional area in the direction of the average flow velocity in the flow basin and the average flow velocity at the inlet. The flow rate flowing out from the outlet is less than or equal to the product of the largest cross-sectional area in the flow basin and the average flow velocity at the outlet.

10. The watershed described above is characterized in that its shape includes at least one thin-sheet watershed.

11. The thin-sheet flow basin is characterized in that, except for the edge of the flow basin and discontinuous places (such as places where the height is 0), the inside of the thin-sheet flow basin is in a laminar state.

12. The thin sheet flow basin is characterized in that the upper and lower walls of the flow basin are unique and parallel to each other, or the inclination angle formed is not greater than 30 degrees.

13. The thin sheet flow basin is characterized in that the upper and lower walls of the flow basin are curved surfaces, and the tangent lines or tangent planes of the two facing points are parallel, or the formed inclination angle is not greater than 30 degrees. In special cases, it is two concentric cylinders.

14. The flow field is characterized in that the direction of movement of each point on the wall constituting the thin flow field is the tangent direction of the point on the wall. Therefore, when the wall moves, it coincides with its shape at the last moment. In special cases, the wall is a plane (translation), a cylinder or a disk (rotation).

15. The flow field is characterized in that the direction of movement of each point on the wall constituting the thin channel is consistent with the direction of movement of the liquid in the fluid channel. When the wall moves, it is parallel to its shape at the last moment.

16. The flow basin is characterized in that the design of at least part of the area of the walls on the upper and lower sides matches the liquid properties or flow process, so that the liquid can be confined in the thin sheet flow basin without side walls. Preferably, for at least part of the flow basin area, the sum of the cosine values of the contact angles of the upper wall and the lower wall opposite thereto on the fluid is greater than or equal to 0.

17. The flow basin is characterized in that at least a portion of the area does not match the liquid properties or flow process, making it difficult for the liquid to overflow across this portion of the area. Preferably, for at least a portion of the flow basin area, the sum of the cosine values of the contact angles of the upper wall and the lower wall opposite thereto with the fluid is less than or equal to 0.

18. The flow basin is characterized in that, in actual operation, the liquid may exceed the designed thin-sheet flow basin and overflow, and the overflowed liquid can be carried away by shear force.

19. The flow field described is characterized in that the shear force is generated due to the relative movement of the walls forming the flow domain.

20. The movement described above is characterized in that at least part of the wall forming the thin-film channel is a flexible but non-stretchable membrane.

21. The flow field described above is characterized in that the wall is a liquid wall or a gas wall formed by immiscible liquid or gas.

22. The flow field is characterized in that the shear force is generated by a portion of the liquid in the sheet being driven by physical methods such as force, heat, light, electricity, or magnetism, such as electrowetting, acoustic energy drive, bubble drive, photodeformation, and magnetic fluid.

23. The flow field is characterized in that the distance between at least some points of the upper and lower surfaces of the thin-sheet channel is 0. In this case, the liquid flows through the gaps between natural microscopic non-smooth surfaces or the gaps between artificially prepared non-smooth surfaces.

24. The flow field can form a stable or substantially stable flow field within one minute.

25. The viscous flow field is characterized in that a substance for viscosity adjustment, preferably glycerol, and/or a surfactant, preferably Tween, is added to the fluid.

26. Different types of fluids are not mixed before they reach the vicinity of the inlet area.

27. A method for using a Couette-like flow field, characterized in that the liquid circuit described in any one of the above, the method for using the flow field comprises:

Fill the inlet of the flow field with fluid.

Apply shear forces to the system.

The fluid remains connected to the fluid outside the flow domain and fills at least the thin flow domain

If necessary, fill the flow field with auxiliary fluid.

If necessary, open the auxiliary inlet/outlet devices at the inlet and outlet.

28. A hardware platform for constructing a Couette-like flow field, named a shear-driven fluid platform, characterized in that it includes:

The solid wall is in contact with the fluid and plays a role in constraining the fluid, and the fluid contains the fluid wall. The space between the walls is the flow domain.

The inlet can be the inlet of the flow field, where the free surface of the fluid is visible; or it can be a shape that has a liquid retention function and is connected to the liquid in the flow field, such as a pipe or a funnel. The surface properties of the device can prevent liquid adhesion. Before reaching the inlet area, different fluids are physically isolated from each other. After reaching the inlet area, the fluids are affected by shear forces.

The driving device includes at least one energy conversion method that can generate shear force on the liquid in the flow area, so that the fluid speed close to a wall is faster than the fluid speed close to other walls. The driving device includes an energy supply device, which can be manpower or power supply.

The flow domain contains material that interacts with the material in the fluid, which can be the solid wall itself or a material fixed to the solid wall. It can be stored in a storage chamber that the liquid will contact, or added from an inlet.

When shear force is applied, at least the thin areas in the basin are filled.

29. The hardware platform, characterized in that the driving device and the wall include:

The moving tensioned membrane serves as the moving wall. The electric energy system is used as the energy supply device, including a reducer, a motor, and a power supply.

30. The hardware platform, characterized in that it also includes a bypass device;

The bypass device is used to discharge excess liquid from the basin to prevent the entire mechanism from being contaminated or liquid accumulation.

31. The hardware platform is characterized in that the positioning device comprises: a mechanical device that fixes the relative position of the moving wall to other walls but weakly constrains the moving direction. In particular, if the moving wall is a liquid wall, the device can be a solid container and certain auxiliary fluid conditions (speed, liquid properties, etc.).

32. The fluid circuit system, characterized in that the positioning device further comprises a gap locking mechanism;

The gap locking mechanism includes a gap enlarging mechanism and a gap reducing mechanism. The gap locking mechanism is connected to different walls, the gap reducing mechanism controls the distance between different walls to prevent further distance, and the gap enlarging mechanism adjusts the distance between the walls to prevent further approach.

33. The platform, characterized in that it also includes a fluid introduction device;

The fluid introduction device is used to add fluid to the inlet of the flow field. The fluid introduction device may have a certain anti-pollution function or be disposable. The fluid introduction device may be other microfluidic chips or microfluidic structures.

34. The platform described above is characterized in that the fluid introduction device includes at least one of coating, transfer, coating (or spraying, printing), mutual exclusion, coating, inkjet, pipette, hollow fiber catheter or guidewire.

35. The platform, characterized in that it also includes a temperature control device;

The temperature control device is used to control the temperature of the reaction.

36. The platform, characterized in that it also includes a detection device;

The detection device is used to detect post-reaction indicators, such as fluorescence, color development, gas production, luminescence, changes in the concentration of at least one product, etc., and/or the absence of a reaction.

37. The fluid circuit system, characterized in that it also includes a control unit;

The control unit is respectively connected to the signals of the electrical components in the hardware platform to control the electrical components and/or read or transmit relevant signals/instructions.

38. A method for using a Couette-like flow field, characterized in that it includes any of the hardware platforms described above, and the method for using the method includes:

Add fluid to the inlet of the hardware platform;

When the drive is turned on, shear forces cause the fluid near one wall to flow faster than the fluid near the other walls.

The fluid fills at least the thin flow area in the flow domain.

When necessary, different types of fluids are added to the inlet, and the different types of fluids do not mix before reaching the inlet area.

When necessary, stop adding fluid to the inlet and pause the drive unit.

39. A microfluidic chip platform, characterized in that it comprises any of the flow fields described above or any of the hardware platforms described above.

The present invention also discloses the following supplementary note 1, including:

Item 1. A liquid path structure, characterized in that it includes

The first wall,

The second wall surface is configured to be disposed close to or at least partially in contact with the first wall surface, and the space facing each other forms a flow domain, wherein the flow domain includes a thin flow domain;

an inlet structure, configured to include one or more inlets, which are in communication with the flow basin when in operation, so that a fluid including at least a first fluid can be introduced into the flow basin; wherein the fluid of the first fluid can be directly introduced into the flow basin without passing through a common pipeline;

An outlet structure, configured to include one or more outlets, which is in communication with the flow field during operation so that the fluid passing through the flow field is discharged;

Wherein, during operation, the first fluid is configured to be able to be applied with energy, and the energy can be converted into fluid kinetic energy, thereby forming a shear flow of the first fluid in the flow domain.

Item 2. The liquid path structure according to Item 1 is characterized in that, during operation, the first wall surface is configured to be able to move relative to the second wall surface, thereby applying energy to the first fluid to drive the shear flow of the first fluid.

Clause 3. The liquid path structure according to clause 2, characterized in that the first wall surface and the second wall surface comprise substantially parallel planes, preferably with an angle of no more than 30 degrees;

Item 4. The liquid path structure according to Item 2 is characterized in that the movement of the first wall surface includes a translation substantially parallel to the second wall surface, a translation in a direction approaching or moving away from the second wall surface, and a rotation relative to the second wall surface.

Item 5. The liquid path structure according to Item 3, characterized in that the first wall surface comprises a bendable film material.

Item 6. The fluid path structure according to Item 1 is characterized in that the first fluid is configured to be able to perform shear flow based on energy applied to it based on one of the effects including force, heat, light, and electricity.

Clause 7. The liquid circuit structure according to clause 1 or 2, characterized in that the inlet structure comprises a first inlet and a second inlet,

wherein the first fluid flows from the first inlet through the flow field and flows out from an outlet of the outlet structure,

The second fluid flows into the flow domain from the second inlet, flows out from one outlet of the outlet structure, and shares an outlet with the first fluid, or flows out from another outlet of the outlet structure, and uses a different outlet with the first fluid, wherein the second fluid and the first fluid are laminar flows in the thin flow domain, and the second fluid occupies a certain space in the thin flow domain so that the required amount of the first fluid is further reduced.

Item 8. The liquid path structure according to Item 7 is characterized in that the second fluid contacts the first fluid in the thin area, and its flow area does not overlap with the first fluid.

Clause 9. The fluid path structure according to clause 1, characterized in that the fluid is introduced through the inlet structure in a time or space discrete manner, comprising:

The inlet structure includes an inlet, into which the first fluids are introduced at different times, or when the first fluids are introduced at the same time, an incompatible fluid is used to separate the first fluids, so that the first fluids will not mix with each other before entering the thin flow area; or

The inlet structure includes a plurality of inlets, and each first fluid is introduced through a different inlet, so that each first fluid will not mix with each other before entering the thin flow area.

Item 10. The liquid path structure according to Item 1 is characterized in that the inlet structure further includes a liquid storage structure for storing a predetermined amount of the first fluid to ensure that a sufficient amount of the first fluid fills the flow domain through the inlet and prevents air from being brought in; wherein the predetermined amount is slightly larger than the fluid capacity required by the flow domain.

Item 11. The liquid path structure according to Item 2 is characterized in that the first wall surface and the second wall surface include curved surfaces to form a sleeve shape, wherein one of the first wall surface and the second wall surface forms an outer tube and the other forms an inner tube, and a flow domain is formed between the two.

Item 12. The fluid path structure according to Item 1 is characterized in that the outlet structure is configured to enable the fluid from the thin flow area to be discharged freely and unobstructed to avoid blockage that affects the introduction of the fluid into the inlet.

Item 13. The liquid path structure according to Item 1 is characterized in that the materials of the first wall and the second wall are selected so that their hydrophilicity and hydrophobicity enable the first fluid to be located between the first wall and the second wall in a free state without being expelled by surface tension.

Item 14. The fluid path structure according to Item 1 is characterized in that the material of the second wall is selected so that it has poor affinity with the first fluid in the flow domain, so that the first fluid flowing out of the flow domain through shear movement will be sucked back into the flow domain.

Item 15. The liquid path structure according to Item 13, characterized in that the sum of the cosine values of the contact angles of the first wall surface and the second wall surface with the first fluid is greater than or equal to zero.

Item 16. The liquid path structure according to Item 1 is characterized in that the inlet includes a free surface, or the fluid connected to the inlet has at least one free surface; the outlet includes a free surface, or the fluid connected to the outlet has at least one free surface.

Clause 17. The liquid path structure according to Clause 1 is characterized in that the thickness dimension of the thin flow domain is one order of magnitude smaller than the length and/or width dimension of the thin flow domain.

Item 18. The liquid path structure according to Item 1 is characterized in that the first fluid between the first wall and the second wall has a velocity gradient, and the first fluid has a faster flow rate on the side affected by energy or with less resistance.

Item 19. The liquid circuit structure according to Item 1 is characterized in that the first fluid includes a liquid, specifically a reagent.

Clause 20. The liquid path structure according to Clause 17 is characterized in that the thickness dimension is sub-millimeter level.

Item 21. A device comprising the fluid path structure of items 1-19.

Clause 22. A method for operating a fluid circuit structure, comprising:

providing a first wall surface,

Providing a second wall surface, which is configured to be disposed close to or at least partially in contact with the first wall surface, and the space facing the second wall surface forms a flow domain, wherein the flow domain includes a thin flow domain;

Providing an inlet structure, configured to include one or more inlets, which are in communication with the flow field when in operation, so that a fluid including at least a first fluid can be introduced into the flow field; wherein the fluid of the first fluid can be directly introduced into the flow field without passing through a common pipeline;

Providing an outlet structure, which is configured to include one or more outlets and is in communication with the flow area during operation so that the fluid passing through the flow area is discharged;

Wherein, during operation, the first fluid is configured to be able to be applied with energy, and the energy can be converted into fluid kinetic energy, thereby forming a shear flow of the first fluid in the flow domain.

Item 23. The operating method of the liquid path structure according to Item 21 is characterized in that, during operation, the first wall surface is configured to be able to move relative to the second wall surface, thereby applying energy to the first fluid to drive the shear flow of the first fluid.

Clause 24. The method for operating the liquid path structure according to clause 22, characterized in that the first wall surface and the second wall surface comprise substantially parallel planes, preferably with an angle of no more than 30 degrees;

Item 25. The method for operating the liquid path structure according to Item 23 is characterized in that the movement of the first wall surface includes a translation substantially parallel to the second wall surface, a translation in a direction approaching or moving away from the second wall surface, and a rotation relative to the second wall surface.

Item 26. The method for operating the liquid path structure according to Item 23, characterized in that the first wall surface comprises a bendable film material.

Item 27. The method for operating a fluid path structure according to Item 21, characterized in that the first fluid is configured to be capable of shear flow when energy is applied based on one of force, heat, light, and electrical effects.

Clause 28. The method for operating the fluid path structure according to clause 21 or 22, wherein the inlet structure comprises a first inlet and a second inlet,

wherein the first fluid flows from the first inlet through the flow field and flows out from an outlet of the outlet structure,

wherein the second fluid flows into the flow field from the second inlet and flows out from the one outlet of the outlet structure, the first fluid and the second fluid share the same outlet, or flows out from another outlet of the outlet structure, the first fluid and the second fluid use different outlets respectively,

The second fluid and the first fluid are laminar flows in the thin flow area, and the second fluid occupies a certain space in the thin flow area so that the required amount of the first fluid is further reduced.

Item 29. The method for operating a liquid path structure according to Item 27, wherein the second fluid contacts the first fluid in the thin region, and its flow region does not overlap with the first fluid.

Clause 30. The method for operating the fluid circuit structure according to clause 21, characterized in that the fluid is introduced through the inlet structure in a time or space discrete manner, comprising:

The inlet structure includes an inlet, into which the first fluids are introduced at different times, or when the first fluids are introduced at the same time, an incompatible fluid is used to separate the first fluids, so that the first fluids will not mix with each other before entering the thin flow area; or

The inlet structure includes a plurality of inlets, and each first fluid is introduced through a different inlet, so that each first fluid will not mix with each other before entering the thin flow area.

Item 31. The operating method of the liquid path structure according to Item 21 is characterized in that the inlet structure further includes a liquid storage structure for storing a predetermined amount of the first fluid to ensure that a sufficient amount of the first fluid fills the flow domain through the inlet and prevents air from being brought in; wherein the predetermined amount is slightly larger than the fluid capacity required by the flow domain.

Item 32. The operating method of the liquid path structure according to Item 22 is characterized in that the first wall surface and the second wall surface include curved surfaces to form a sleeve shape, wherein one of the first wall surface and the second wall surface forms an outer tube and the other forms an inner tube, and a flow domain is formed between the two.

Clause 33. The method for operating the fluid path structure according to Clause 21 is characterized in that the outlet structure is configured to enable the fluid from the thin flow area to be discharged freely and unobstructed to avoid blockage that affects the introduction of the fluid into the inlet.

Item 34. The operating method of the liquid path structure according to Item 21 is characterized in that the materials of the first wall and the second wall are selected so that their hydrophilicity and hydrophobicity enable the first fluid to be located between the first wall and the second wall in a free state without being expelled by surface tension.

Item 35. The fluid path structure according to Item 21 is characterized in that the material of the second wall is selected so that it has poor affinity with the first fluid in the flow domain, so that the first fluid flowing out of the flow domain by shear movement will be sucked back into the flow domain.

Item 36. The method for operating a liquid path structure according to Item 33, wherein the sum of the cosine values of the contact angles of the first wall surface and the second wall surface with the first fluid is greater than or equal to 0.

Item 37. The operating method of the liquid path structure according to Item 21 is characterized in that the inlet includes a free surface, or the fluid connected to the inlet has at least one free surface; the outlet includes a free surface, or the fluid connected to the outlet has at least one free surface.

Clause 38. The method for operating the liquid path structure according to Clause 21 is characterized in that the thickness dimension of the thin flow domain is one order of magnitude smaller than the length and/or width dimension of the thin flow domain.

Item 39. The operating method of the liquid path structure according to Item 21 is characterized in that the first fluid between the first wall and the second wall has a velocity gradient, and the first fluid has a faster flow rate on the side affected by energy or with less resistance.

Clause 40. The method for operating the fluid path structure according to Clause 21, characterized in that the first fluid comprises a liquid, specifically a medicine.

Item 41. The liquid path structure according to Item 37 is characterized in that the thickness dimension is sub-millimeter level.

It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other. As for the method disclosed in the embodiment, since it corresponds to the system disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the system part description.

Claims (80)

A liquid path structure, characterized in that it comprises The first wall, The second wall surface is configured to be disposed close to or at least partially in contact with the first wall surface, and the space facing each other forms a flow domain, wherein the flow domain includes a thin flow domain; an inlet structure configured to include one or more inlets, which are in communication with the flow field when in operation, so that a fluid including at least a first fluid can be introduced into the flow field; an outlet structure configured to include one or more outlets, which are in communication with the flow field when in operation, so that the fluid passing through the flow field can be discharged; wherein the first fluid comprises a liquid; Among them, when working: The fluid at at least one inlet position of the inlet structure can be directly exposed to the environment outside the flow field without passing through a pipeline; and/or The fluid at at least one outlet position of the outlet structure can be directly exposed to the environment outside the flow field without passing through a pipeline, and/or The fluid at at least one location in the flow basin can be directly exposed to the environment outside the flow basin; The first fluid is configured to be able to be applied with energy during operation, and the energy can be converted into fluid kinetic energy, thereby forming a shear flow of the first fluid in the flow domain, and the thin flow domain can be emptied or filled with the fluid during operation. The fluid path structure according to claim 1, wherein, during operation, the first wall surface is configured to be able to move relative to the second wall surface, thereby applying energy to the first fluid to drive the shear flow of the first fluid. The liquid path structure according to claim 2, wherein the relative movement of the first wall surface includes a translation in a direction substantially parallel to the second wall surface, a translation in a direction approaching or moving away from the second wall surface, and a rotation relative to the second wall surface. The liquid path structure according to claim 3, wherein the first wall surface rotates relative to the second wall surface comprises the first wall surface rotating and the second wall surface being stationary. The liquid path structure according to claim 4, wherein the first wall surface and the second wall surface include a disc shape, the first wall surface is substantially flat, the second wall surface is substantially flat, and the first wall surface is substantially parallel to the second wall surface; During operation, the first wall surface is configured to rotate so as to apply energy to the first fluid and drive the first fluid to traverse the second wall surface. The fluid path structure according to claim 1, wherein the first fluid is configured to be capable of shear flow when energy is applied based on one of force, heat, light, and electrical effects. The liquid circuit structure according to claim 1, wherein the inlet structure comprises a first inlet and a second inlet, The first fluid flows into the flow basin from the first inlet, passes through the flow basin, and flows out from an outlet of the outlet structure, and the second fluid flows into the flow basin from the second inlet, passes through the flow basin, flows out from the one outlet of the outlet structure, and shares an outlet with the first fluid, or flows out from another outlet of the outlet structure, and uses different outlets with the first fluid, wherein the second fluid and the first fluid are laminar flows in the thin flow basin, and the second fluid occupies a certain space in the thin flow basin so that the required amount of the first fluid is further reduced. The liquid path structure according to claim 7, wherein the second fluid contacts the first fluid in the thin flow region, and its flow area does not overlap with the first fluid. The fluid path structure according to claim 7, wherein the movement of the second fluid can drive the first fluid to perform shear flow. The liquid circuit structure according to claim 1, wherein the fluid can be introduced in a temporally or spatially discrete manner through the inlet structure, wherein: The inlet structure includes an inlet, into which the first fluids are introduced at different times, or when the first fluids are introduced at the same time, an incompatible fluid is used to separate the first fluids, so that the first fluids will not mix with each other before entering the thin flow area; or The inlet structure includes a plurality of inlets, and each first fluid is introduced through a different inlet, so that each first fluid will not mix with each other before entering the thin flow domain. The fluid path structure according to claim 1, wherein the inlet structure further comprises a liquid storage structure for storing a predetermined amount of the first fluid to ensure that a sufficient amount of the first fluid fills the flow area through the inlet and prevents air from being brought into the flow area; Wherein, the predetermined amount is configured to be slightly larger than the fluid capacity required by the flow domain. The liquid path structure according to claim 1, wherein the first wall surface and the second wall surface include curved surfaces to form a sleeve shape, wherein one of the first wall surface and the second wall surface forms an outer cylinder, and the other forms an inner cylinder, and a flow domain is formed between the two. When working, at least one of the outer cylinder and the inner cylinder can move, and the movement includes: rotation or axial linear motion or axial linear motion while rotating. The liquid path structure according to claim 12, wherein the first wall surface forms an outer cylinder, the second wall surface forms an inner cylinder, the inner cylinder moves, and the outer cylinder is stationary, including: rotating and/or axially moving. The liquid path structure according to claim 13, wherein the height of the inner cylinder is lower than that of the outer cylinder. The liquid path structure according to claim 12 or 14, wherein The inner cylinder and the outer cylinder both comprise cylinders; or The inner cylinder comprises a multi-faceted cylindrical cylinder, and the outer cylinder comprises a cylindrical cylinder; or The outer cylinder comprises a multi-faceted cylindrical cylinder, and the inner cylinder comprises a cylindrical cylinder. The fluid path structure according to claim 1, wherein the outlet structure is configured to enable the fluid from the thin flow region to be discharged freely and unobstructed to avoid blockage that affects the introduction of the fluid into the inlet. The liquid path structure according to claim 1, wherein the materials of the first wall surface and the second wall surface are selected so that their hydrophilicity and hydrophobicity enable the first fluid to be located between the first wall surface and the second wall surface in a free state without being expelled by surface tension, for example, the hydrophilic and hydrophobic material comprises an HMDS coating. The fluid path structure according to claim 1, wherein the material of the second wall is selected so as to have poor affinity with the first fluid in the flow domain, so that the first fluid flowing out of the flow domain by shear flow will be sucked back into the flow domain. The liquid path structure according to claim 17, wherein the sum of cosine values of contact angles of the first wall surface and the second wall surface with the first fluid is greater than or equal to 0. The fluid path structure according to claim 1, wherein the inlet includes a free surface, or the fluid connected to the inlet has at least one free surface; the outlet includes a free surface, or the fluid connected to the outlet has at least one free surface. The liquid path structure according to claim 1, wherein the thickness dimension of the thin flow domain is at least one order of magnitude smaller than the length and/or width dimension of the thin flow domain. The liquid path structure according to claim 21, wherein the thickness of the thin flow domain is 2-100 microns. The liquid path structure according to claim 1, wherein the first fluid between the first wall surface and the second wall surface has a velocity gradient, and the first fluid has a faster flow velocity on the side affected by energy or with less resistance. The liquid circuit structure according to claim 1, wherein the liquid circuit structure further comprises a heater; The heater is configured to perform heat transfer with the first wall surface and/or the second wall surface for heating the flow area. The liquid path structure according to claim 24, wherein the flow domain includes a plurality of temperature zones, and the plurality of temperature zones are respectively separated by at least one insulating block arranged on the second wall surface, wherein the temperatures of the plurality of temperature zones are the same or different. The fluid path structure according to claim 1, wherein the first wall and the second wall comprise a disc shape, and during operation, the second wall is configured to be able to rotate, thereby applying energy to the first fluid to drive the shear flow of the first fluid. The liquid path structure according to claim 26, wherein the first wall surface is configured to be stationary, or to rotate, or to make a linear motion in a direction substantially parallel to the second wall surface, or to rotate and make a linear motion in a direction substantially parallel to the second wall surface. The liquid path structure according to claim 26, wherein: The inlet structure includes a channel provided at a predetermined position of the first wall surface and/or the second wall surface, for introducing the fluid into the flow domain. The liquid path structure according to claim 28, wherein the channel includes a through hole arranged on the first wall surface and/or the second wall surface at a position close to the center of the disk. The liquid path structure according to claim 28, wherein the channel includes a liquid inlet pipe attached to the first wall and/or the second wall, so that the first fluid is sucked into the flow domain. The fluid path structure according to claim 26, wherein the outlet structure comprises an area between the disc periphery of the first wall surface and the disc periphery of the second wall surface, and the first fluid can be discharged through the area. A device comprising the liquid path structure according to any one of claims 1 to 31. A method for operating a liquid circuit structure, comprising: providing a first wall surface, Providing a second wall surface, which is configured to be disposed close to or at least partially in contact with the first wall surface, and the space facing the second wall surface forms a flow domain, wherein the flow domain includes a thin flow domain; Providing an inlet structure configured to include one or more inlets, which are in operative communication with the flow field so that a fluid including at least a first fluid can be introduced into the flow field; Providing an outlet structure, which is configured to include one or more outlets and is in communication with the flow area during operation so that the fluid passing through the flow area is discharged; wherein the first fluid comprises a liquid; Among them, when working: The fluid at at least one inlet position of the inlet structure can be directly exposed to the environment outside the flow field without passing through a pipeline; and/or The fluid at at least one outlet position of the outlet structure can be directly exposed to the environment outside the flow field without passing through a pipeline, and/or The fluid at at least one location in the flow basin can be directly exposed to the environment outside the flow basin; The first fluid is configured to be able to be applied with energy, and the energy can be converted into fluid kinetic energy, thereby forming a shear flow of the first fluid in the flow domain, and the thin flow domain can be emptied or filled with the fluid during operation. The operating method according to claim 33, wherein, during operation, the first wall surface is configured to be able to move relative to the second wall surface, thereby applying energy to the first fluid to drive the shear flow of the first fluid. The operating method according to claim 34, wherein the relative movement of the first wall surface includes translation in a direction substantially parallel to the second wall surface, translation in a direction approaching or moving away from the second wall surface, and rotation relative to the second wall surface. The operating method according to claim 35, wherein the first wall surface rotates relative to the second wall surface comprises the first wall surface rotating and the second wall surface being stationary. The operating method according to claim 36, wherein the first wall surface and the second wall surface comprise a disc shape, the first wall surface is substantially planar, the second wall surface is substantially planar, and the first wall surface is substantially parallel to the second wall surface; During operation, the first wall surface is configured to rotate so as to apply energy to the first fluid and drive the first fluid to traverse the second wall surface. The operating method according to claim 33, wherein the first fluid is configured to be capable of shear flow when energy is applied based on one of force, heat, light, and electrical effects. The operating method according to claim 33, wherein the inlet structure comprises a first inlet and a second inlet, wherein the first fluid flows from the first inlet through the flow field and flows out from an outlet of the outlet structure, The second fluid flows into the flow field from the second inlet and flows out from the one outlet of the outlet structure, and the first fluid and the second fluid share one outlet, or flows out from another outlet of the outlet structure, and the first fluid and the second fluid use different outlets respectively. The second fluid and the first fluid are laminar flows in the thin flow area, and the second fluid occupies a certain space in the thin flow area so that the required amount of the first fluid is further reduced. The operating method according to claim 39, wherein the second fluid contacts the first fluid in the thin flow region, and its flow area does not overlap with the first fluid. The operating method according to claim 39, wherein the movement of the second fluid can drive the first fluid to perform shearing movement. The operating method according to claim 33, wherein the fluid is introduced through the inlet structure in a temporally or spatially discrete manner, wherein: The inlet structure includes an inlet, into which the first fluids are introduced at different times, or when the first fluids are introduced at the same time, an incompatible fluid is used to separate the first fluids, so that the first fluids will not mix with each other before entering the thin flow area; or The inlet structure includes a plurality of inlets, and each first fluid is introduced through a different inlet, so that each first fluid will not mix with each other before entering the thin flow domain. The operating method according to claim 33, wherein the inlet structure further includes a liquid storage structure for storing a predetermined amount of the first fluid to ensure that a sufficient amount of the first fluid fills the flow basin through the inlet and prevents air from being brought in; wherein the predetermined amount is slightly larger than the fluid capacity required by the flow basin. The operating method according to claim 33, wherein the first wall surface and the second wall surface include curved surfaces to form a sleeve shape, wherein one of the first wall surface and the second wall surface forms an outer cylinder, and the other forms an inner cylinder, and a flow domain is formed between the two. During operation, at least one of the outer cylinder and the inner cylinder can move, and the movement includes: rotation or axial linear motion or axial linear motion while rotating. The operating method according to claim 44, wherein the first wall surface forms an outer cylinder, the second wall surface forms an inner cylinder, the inner cylinder moves, and the outer cylinder is stationary, and the movement includes: rotation and/or axial movement. The operating method according to claim 45, wherein the inner cylinder is configured to be lower in height than the outer cylinder. The operating method according to claim 45 or 46, wherein: The inner cylinder and the outer cylinder both comprise cylinders, or The inner cylinder comprises a multi-faceted cylinder and the outer cylinder comprises a cylinder, or The outer cylinder comprises a multi-faceted cylinder and the inner cylinder comprises a cylindrical cylinder. The operating method according to claim 47, wherein the inner cylinder comprises a multi-faceted cylinder and the outer cylinder comprises a cylinder, further comprising the steps of: S1. A chip is disposed on the cylindrical surface of the multifaceted cylinder, the chip facing the outer cylinder and being located in the flow field between the inner cylinder and the outer cylinder; S2. providing a first first fluid through the inlet until the space between the inner cylinder and the outer cylinder is filled with the first first fluid, wherein the first first fluid is a liquid, preferably, pure water, or IPA, or Acetone; S3. The outer cylinder starts to rotate and axially reciprocate, while the first first fluid is continuously added, and the first first fluid continuously flows out from the outlet. S4. As the outer cylinder moves, the first first fluid moves, and the first first fluid approaches laminar flow where the inner wall of the inner cylinder and the outer cylinder are close to each other; S5. Provide a second first fluid into the flow field through the inlet to clean the chip on the surface of the inner cylinder; the second first fluid includes a high-pressure gas and/or a surfactant; S6. Lower the inner cylinder to expose the chip surface, and dry the surface with high-pressure air. S7. Take out the chip, This completes the cleaning of the chip. The operating method according to claim 33, wherein the outlet structure is configured to enable the fluid from the thin flow basin to be discharged freely and unobstructed to avoid blockage that affects the introduction of the fluid into the inlet. The operating method according to claim 33, wherein the materials of the first wall and the second wall are selected such that their hydrophilicity and hydrophobicity enable the first fluid to be located between the first wall and the second wall in a free state without being expelled by surface tension, for example, the hydrophilic and hydrophobic material comprises an HMDS coating. The operating method according to claim 33, wherein the material of the second wall is selected so that it has poor affinity with the first fluid in the flow domain, so that the first fluid flowing out of the flow domain by shear flow will be sucked back into the flow domain. The operating method according to claim 50, wherein the sum of cosine values of contact angles of the first wall surface and the second wall surface with the first fluid is greater than or equal to 0. The operating method according to claim 33, wherein the inlet includes a free surface, or the fluid connected to the inlet has at least one free surface; the outlet includes a free surface, or the fluid connected to the outlet has at least one free surface. The operating method according to claim 33, wherein the thick dimension of the thin flow basin is at least one order of magnitude smaller than the long and/or wide dimensions of the thin flow basin. The operating method according to claim 54, wherein the thickness of the thin flow domain is 2-100 microns. The operating method according to claim 33, wherein the first fluid between the first wall and the second wall has a velocity gradient, and the first fluid has a faster flow rate on the side affected by energy or with less resistance. The operating method according to claim 33, wherein the liquid path structure further comprises a heater, and the heater is configured to transfer heat with the first wall surface and/or the second wall surface to heat the flow domain. The operating method according to claim 33, wherein the flow domain includes a plurality of temperature zones, and the plurality of temperature zones are respectively separated by at least one insulating block arranged on the second wall surface, wherein the temperatures of the plurality of temperature zones are the same or different. The operating method according to claim 33, wherein the first wall surface and the second wall surface comprise a disc shape, the first wall surface is substantially planar, the second wall surface is substantially planar, and the first wall surface is substantially parallel to the second wall surface; During operation, the second wall surface is configured to be able to rotate relative to the first wall surface, thereby applying energy to the first fluid and driving the shear flow of the first fluid. The operating method according to claim 58, wherein the first wall surface is configured to be stationary, or to rotate, or to make a linear motion in a direction substantially parallel to the second wall surface, or to rotate and make a linear motion in a direction substantially parallel to the second wall surface. The operating method according to claim 59, wherein the second wall surface includes a chip, the second wall surface is configured to have hydrophilic regions and hydrophobic regions arranged alternately, wherein biomolecules are fixed on the hydrophilic regions, the biomolecules include single-stranded DNA, the hydrophobic regions are covered with hydrophobic substances, and the area of the first wall surface is greater than or equal to the area of the second wall surface; the operating method further comprises: S1. providing a first first fluid through the inlet structure, wherein the first first fluid comprises a reagent capable of disconnecting an azide group, so that a first reaction between the first first fluid and the biomolecule occurs; S2. providing a second first fluid through the inlet structure, wherein the second first fluid comprises a buffer reagent for cleaning the first first fluid and the product of the first reaction; S3. providing a third first fluid through the inlet structure, wherein the third first fluid comprises a synthetic reagent containing four bases ACTG and corresponding dye groups, so as to cause a second reaction between the third first fluid and the biomolecule; S4. Providing the fourth first fluid through the inlet structure, the fourth first fluid comprising a buffer reagent for cleaning the third first fluid, wherein the fourth first fluid and the second first fluid are buffer reagents of the same or different components; S5. recording and determining the base type of the product of the third reaction on the chip by sensing; Repeat steps S1-S5 multiple times to obtain the base sequence of the DNA single strand based on the base types of the product of the third reaction. The operating method according to claim 61, wherein between step S4 and step S5, further comprising the step of: S4.1. providing a fifth first fluid through the inlet structure, wherein the fifth first fluid comprises a synthetic reagent containing four bases ACTG and corresponding dye groups, so that a fourth reaction of the fifth first fluid with the biomolecule occurs; S4.2. The sixth first fluid is provided through the inlet structure, wherein the sixth first fluid includes a buffer reagent for cleaning the fifth first fluid, wherein the sixth first fluid and the second first fluid and the fourth first fluid are buffer reagents of the same or different components. According to the operating method according to claim 61 or 62, the operating method further includes: immediately before step S5, it also includes the step of: providing a seventh first fluid through the inlet structure, the seventh first fluid including a protective reagent to avoid the recording process causing adverse effects on the DNA. The operating method according to claim 61, wherein the first fluid comprises a triphenylphosphine solution. According to the operating method of claim 64, the recording by sensing in step S5 includes: taking pictures to record the fluorescence on the chip, and determining the type of the base by a basecall algorithm. The operating method according to claim 65, wherein the outlet structure includes an area between the disc periphery of the first wall and the disc periphery of the second wall, enabling the first fluid to be discharged through the area, and the operating method further comprises: A waste liquid collecting structure is provided for collecting the discharged first fluid. The operating method according to claim 61, wherein in step S2, the reaction time of the first reaction is 1 minute. The operating method according to claim 61, wherein in step S2, the volume of the second first fluid is 3 times the volume of the flow basin. The operating method according to claim 61, wherein in step S3, the volume of the third first fluid is 1.5 times the volume of the flow basin, The operating method according to claim 61, wherein in step S3, the second reaction is carried out at a temperature of 55°C, and the reaction time of the second reaction is 1 minute. The operating method according to claim 59, wherein the inlet structure includes a channel arranged at a predetermined position of the first wall and/or the second wall, for introducing the fluid into the flow field. An operating method according to claim 71, wherein the channel comprises a through hole arranged on the first wall surface and/or the second wall surface at a position close to the center of the disk. An operating method according to claim 71, wherein the channel comprises a liquid inlet pipe attached to the first wall and/or the second wall, so that the first fluid is sucked into the flow domain. The operating method according to claim 71, wherein the outlet structure includes an area between the disc periphery of the first wall and the disc periphery of the second wall, enabling the first fluid to be discharged through the area. A method for operating a liquid circuit structure, comprising: Providing a conduit, the conduit comprising an inlet structure and an outlet structure, the inlet structure comprising at least one inlet, the outlet structure comprising at least one outlet; In operation, a first fluid and a second fluid incompatible with the first fluid are introduced into the pipeline through different inlets of the at least one inlet, respectively, wherein the first fluid and the second fluid are discharged through the at least one outlet, and a flow domain is formed between the inlet structure and the outlet structure; The second fluid occupies a certain volume of the flow domain to form a thin flow domain of the first fluid. The operating method according to claim 75, wherein the second fluid flows in the pipe, driving the first fluid to shear flow in the pipe. The operating method according to claim 75, wherein the second fluid is configured so as not to undergo macroscopic flow. The operating method according to claim 75, wherein the thickness of the thin flow region is at least 2 microns. The operating method according to claim 75, wherein the inlet structure includes a solenoid valve configured to control the introduction of the first fluid and the second fluid into the pipeline. The liquid path structure according to any one of claims 1-31, wherein the liquid path structure is a microfluidic liquid path structure.