JPS62134536A - Duplex pipet - Google Patents

Abstract

PURPOSE:To form a duplex pipet suitable for the measurement of ion activity, by a method wherein a pair of housing are connected in a freely revolvable manner and cylinders are provided to the lower parts of the housings to hold a pair of piston members and the housing are mutually engaged when the interval thereof reached a predetermined distance or less to be made integrally slidable. CONSTITUTION:When dripping chips 2 are mounted to mount parts 12, 32 and housings 10, 30 are revolved to an open position around a hinge 1, for example, it becomes easy that only one dripping chip is immersed in a regent bottle to absorb a reagent. Because push rods 21, 41 can be independently operated, the push rod in a sucking side is pushed down to make it possible to suck a liquid specimen or a reference liquid. Subsequently, both housings 10, 30 are revolved to be positioned in a closely contacted state and the lower ends of the dripping chips are respectively opposed to a part of liquid spot-depositing holes and, when both push rods 21, 41 are pushed down, the liquid specimen and the reference liquid can be simultaneously deposited and supplied in a spot form. When one of both push rods 21, 41 are pushed by engaging an engaging member 3 with an engaging groove 21b, both of them are simultaneously moved downwardly to make it possible to perform simultaneous spot-dripping.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a dual pipette, that is, a dual pipette capable of inhaling and discharging two types of liquids, and more particularly to a sliding pipette for measuring ion activity. The present invention relates to a dual pipette suitable for dot-feeding a sample liquid and a reference liquid to an instrument.

(Conventional technology) Aqueous liquid samples, e.g. alcoholic beverages, drinks, running water.

In particular, there is an ion activity measuring device for quantitatively analyzing the activity (or degree) of a specific ion contained in biological fluids (blood, urine, saliva, etc.) using potentiometry. JP-A-58411648@.

This method is disclosed in Japanese Patent Application Laid-Open No. 59-30055M, Japanese Patent Application No. 11744-1980, and the like.

Generally, such an ion activity measurement device is provided with at least one pair of ion-selective electrodes having an ion-selective layer as the outermost layer that selectively responds to specific ions. It is supported between an upper frame and a lower support frame.A pair of liquid spotting holes are provided in the upper frame so as to correspond to one set of the ion-selective electrode pair. A porous bridge (a preferred example is a twisted thread made of fibers) that achieves electrical continuity (liquid junction) between the sample liquid dotted to one side of the dot hole and the reference liquid dotted to the other side of the dot hole. It is usually provided on this upper frame.Also,
When there are a plurality of pairs of ion-selective electrodes, generally a pair of porous liquid distribution members connecting these pairs of ion-selective electrodes and the pair of spotting holes are connected to the upper frame and the ion-selective electrodes. It is placed between the pair.

In an ion activity measuring instrument configured in this way, for example, if three ion-selective electrode pairs are provided, each of which responds to NaΦ, Φ, and cze, the activities of these ions are known. When a reference liquid is spotted on one of a pair of liquid spotting holes, and a sample liquid whose ion activity is unknown is spotted on the other (both liquids are spotted at the same time). (preferably) both liquids permeate each porous liquid distribution member and reach the corresponding ion-selective electrode. On the other hand, the interfaces of both liquids come into contact (liquid junction) near the center of the porous bridge, establishing electrical continuity. As a result, a potential difference corresponding to the difference in activity of each ion between the sample solution and the reference solution is generated between the electrodes of each ion-selective electrode pair. The activities of NaΦ, Φ, and c9Je ions in the sample solution can be measured simultaneously, sequentially, or at any time using a calibration curve determined in advance from the activities (the principle is based on Nernst's equation).

This type of ion activity measurement device can easily measure the ion activity by simply checking a small amount of the sample solution and reference solution once, so it is useful for the analysis of aqueous liquid samples, especially blood collected from the human body. It is extremely useful in clinical analysis of samples obtained.

When spotting a sample solution and a reference solution onto such an ion activity measurement device, it is preferable that both solutions be spotted at substantially the same time, so a spotting supply means suitable for the spotting operation is desired. Ta. Particularly when performing a simple measurement of ion activity, it is convenient to use a dual pipette as a spot supply means, as it can inhale and expel both the sample solution and reference solution without mixing them. be.

The double pipette has a pair of tip parts, and the sample liquid and the reference liquid are simultaneously dripped and supplied from the pair of tip parts to the pair of liquid spotting holes of the ion activity measuring instrument. It is preferable that the configuration is as follows.

In other words, when dispensing liquid, one of the double pipettes
It is preferable that the distance between the pair of tips is approximately the same as the distance between the pair of liquid spotting holes of the ion activity measuring instrument.

However, the distance between the centers of the pair of liquid spotting holes of the ion activity measuring device is usually 10. If the pair of tips of the dual pipette have such a narrow gap, these tips will allow the sample solution and reference solution to be transferred from the blood collection tube, reagent bottle, etc. to the double pipette. It is extremely difficult to inhale into the tip.

Particularly when measuring ion activity using a biological body fluid as a sample liquid, it is preferable to drop and supply the body fluid collected from the biological body onto the ion activity measuring instrument as quickly as possible without exposing it to the outside air. In other words, the dual pipette may have a structure that allows it to directly aspirate a sample liquid from within an organism, etc., and to simultaneously drip-feed this sample liquid together with a separately aspirated reference liquid to a pair of spotting holes in the ion activity device. desirable. However, a dual pipette having such a structure has not been known to date.

(Object of the Invention) In view of the current situation, the present invention aims to provide a dual pipette suitable for measuring ion activity using the slide type ion activity measuring instrument as described above. be.

(Structure of the Invention) The double pipette of the present invention has a pair of housings connected to each other so as to be freely rotatable around an axis extending vertically, and a cylinder is provided at the lower part of each of these housings, and a lower end portion is provided with a cylinder. A pair of piston members arranged so as to be able to slide up and down within the cylinder are held by a housing or a cylinder, and a dripping tip mounting portion communicating with each cylinder is provided at the lower end of each housing or each cylinder. A locking member is attached to the pair of piston members, which locks both piston members to each other when the distance between the piston members becomes less than a predetermined distance. Both piston members are characterized in that they slide integrally.

In the present invention, the term "dropping tip" refers to a tip capable of dropping a sample solution and a reference solution with an appropriate barrier (usually several tens of μm) for measuring ion activity using a slide-type ion activity measuring device. means a distal tip with a hole. This dripping tip (hereinafter sometimes simply referred to as a tip) preferably has a shape that allows it to be freely attached to the connecting member.

In particular, since it is essential for the tip that sucks and holds the sample liquid to be clean for each sample, it is preferable that the tip required for the sample liquid side has a shape that can be detachably attached to the connecting member.

The means for operating the piston member may be manual or automatic, and for example, a known vertical movement mechanism using pneumatic pressure, hydraulic pressure, or N magnetic force (solenoid, electric motor, etc.) may be used.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 and FIG. 2 are perspective views showing an example of a double pipette of the present invention, and this double pipette has a pair of housings 10 and 10.
．． A pair of piston parts +J 20.40 are disposed within 30. As shown in the plan view of FIG. 3, both housings 10 and 30 are connected by a hinge 1 so as to be rotatable about an axis extending vertically.
On the other hand, the second housing 30 can rotate about 90' in the direction of arrow B, as shown by the solid line and chain line. FIG. 4 roughly shows this double pipette in cross section along the arrow A-A in FIG. 3, and will be described below using FIGS. 1 to 4 together.

A pair of housings 10.30 connected by the hinge 1 as described above each have a cylinder 11.30 at the bottom thereof.
31, and roughly at the lower end of this housing 10.30 there is a communication hole 11a communicating with each cylinder 11.31,
A dripping tip mounting portion 12.32 having a diameter 31a and to which the dripping tips 2, 2 can be detachably attached is formed. A pair of piston members 20.30 extend vertically within the housing 10.30. ao is placed.

This piston member 20. ao are bush rods 21 and 41 located at the upper end and protrude upward from the upper surface of the housing 10.30, and a cylinder it is located at the lower end.
, 31 to be able to slide vertically within the cylinder It, 31, and a connecting rod 22.42 that connects the bushing rod 21.41 and the piston rod 23.43, They are biased upwardly against the housing 10.30 by upper coil springs 25.45 and lower coil springs 26.4&, respectively. Note that this urging force is stopped by the contact between the step portions 21a, 41a of the bushing rod 21.41 and the contact portion 13.33 of the housing 10.30.

Further, at the lower end of the housing 10.30, there is provided a housing 10.
A chip ejector 14° 34 is provided which can move up and down inside. The tip ejectors 14, 34 are each connected to an ejector knob 15.35 mounted on the external side of the housing 10.30.
By operating the ejector knob 15.35 downward, the tip ejectors 14, 34 can be pushed down and the dripping tip 2.2 attached to the dripping tip attachment part 12.32 can be removed. This makes it possible to remove the dropper tip that is no longer needed from the pipette after dropping the sample liquid or reference liquid without touching it with your hands.

Roughly speaking, there is a locking groove 2 on the inner surface of the first bushing rod 21.
1b is formed, and a locking member 3 is attached to the inner surface of the second bushing rod 41. When the pair of housings 10 and 30 are in a position where their side surfaces are in close contact with each other as shown in FIG. In this position (hereinafter referred to as the close contact position), as shown in FIG. 4, the locking member 3 enters the locking groove 21b and both bushing rods 21, 41 are locked with each other. Therefore, in the close contact position, both bushing rods 21.41 move up and down only integrally. On the other hand, when one side of the housing 10.30 is rotated approximately 90 degrees from the closed position and opened as shown in Fig. 2 (hereinafter, this position is referred to as the open position), the latching The locking of the member 3 with the locking groove 21b is released, and the bushing rod 21 and the AI
Each can be moved up and down independently.

Note that a protrusion 10a that protrudes laterally is formed at the upper end of the first housing 10, but this is because when the pipette is held in the hand and the bushing rod 21.41 is pushed down, the hand does not touch the protrusion 10a. It comes into contact and receives a downward force,
This is to make it easier to push down the bushing rod 21.41.

The operation and operation of the dual pipette constructed as above will be explained.

When using this dual pipette, first attach it to each dripping tip mounting portion 12.32: the dripping tip 2.26 for sucking and holding the sample liquid or reference liquid. Then, the housing 10.30 is rotated about the hinge 1 from the closed position to the open position. When rotated in this way, the distance between both piston members 20 and 40 is as shown in FIG.
What was dl in the close position is dz in the open position
(>61 ), which makes it easy to immerse only one dropping tip 2 into the reagent bottle when inhaling a sample liquid or reference liquid contained in a reagent bottle, for example.

In addition, since each bushing rod 21.41 can be operated independently in the open position, after pushing down the bushing rod on the side to be inhaled, for example bushing rod 21, and moving the piston rod 23 downward, the lower end of the dripping tip 2 is inserted into the reagent bottle. When the bushing rod 21 is immersed in the sample solution or the reference solution in the dripping tip 2, and then the bushing rod 21 is released, the bushing rod 21 and the piston rod 23 move upward due to the biasing forces of the upper and lower coil springs 25 and 26, and the bushing rod 21 and the piston rod 23 move upward into the dripping tip 2. The sample solution or reference solution is aspirated. Similarly, a predetermined liquid is sucked into the other dripping tip 2, and then both housings 10, 30 are rotated to position them in close contact. The distance d1 between both piston rods 20 and 40 corresponds to the distance between the pair of liquid spotting holes of the slide type ion activity measurement device, and therefore it can be attached to the double pipette. The lower ends of the dripping tips 2, 2 are placed opposite each of the pair of liquid spotting holes, and both bushing rods 21.4
1 at the same time, the sample liquid and reference liquid can be spotted and supplied to these liquid spotting holes at the same time.

Note that this bushing rod 2L 41 is designed to move only in one piece by engagement with the locking member 3 and the locking groove 21b, so if at least one of the bushing rods 21 and 41 is pushed, both will move downward at the same time. , simultaneous arrival can be performed.

In the above, we have described the case where the sample solution and the reference solution are spotted at the same time, but it is theoretically possible to spot both solutions separately if the dual pipette is used in the open position. In addition, when spotting both solutions separately, for example, in an ion activity measuring instrument having multiple ion-selective electrode pairs, the viscosity of the sample solution is high and the diffusion speed in the liquid distribution member is slow. There are cases where only the sample solution is spotted earlier.

In addition, it is preferable to provide a locking mechanism that can securely hold the dual pipette of the present invention in the closed @ position and the open position, such as a detent mechanism using a spring or the like, so that the housing can be fixedly held in the same position. desirable.

(Effects of the Invention) As described above, according to the present invention, a pair of cylinders are formed in a pair of housings that are rotatably connected to each other by a hinge around an axis that extends vertically, and A piston member is provided that slides up and down,
When the distance between the piston members narrows as the housing rotates, the locking member locks both piston members to form a double pipette, so sample liquid or reference liquid can be collected using this pipette. When inhaling, the housing can be rotated to the open position to widen the gap between both piston members, making it easier to inhale from a reagent bottle, etc. In addition, in the open position, each piston member is independent. The sample liquid and reference liquid can be separately inhaled and collected for each piston member. Roughly speaking, when dispensing, by rotating the housing to the close contact position and locking both piston members,
Since both piston members can be operated integrally, it is easy to apply both liquids at the same time. By setting the spacing to be the same as the spacing between the liquid spotting holes, it is possible to easily apply the liquid to the liquid spotting holes at the same time.

As described above, the dual pipette according to the present invention is not only particularly suitable for measuring ion activity using a slide-type ion activity measuring instrument, but also suitable for sliding-type dry liquid colorimetric analysis instruments other than ion activity measurement, It is suitable for spotting sample solutions and standard solutions onto color test paper, colorimetric test pieces, etc., and its utility value is extremely high.

[Brief explanation of drawings]

1 and 2 are perspective views showing one embodiment of the double pipette of the present invention, FIG. 3 is a plan view of the double pipette of FIG. 1, and FIG.
FIG. 2 is a cross-sectional view of the dual pipette of the present invention taken along arrow A-A in the figure; 1... Hinge 2... Dripping tip 3...
- Locking member 10.30...Housing 11.
31... Cylinder 14.34... Chip ejector 20, 40... Piston member 21.41... Bush rod 23, 43... Piston rond Figure 1 Figure 2 Figure 3

Claims (1)

[Scope of Claims] 1 connected to each other so as to be rotatable about an axis extending vertically
a pair of housings, a pair of cylinders each provided at the lower part of the housing, and a pair of pistons each having a lower end slidable up and down within the cylinder and extending up and down and held in the housing or the cylinder. and a dripping tip attachment part provided at the lower end of each housing or cylinder so as to communicate with each cylinder, and the pair of piston members has a dripping tip attachment part provided at a lower end of each of the housings or the cylinders, and the pair of housings rotates on the pair of piston members. A locking member is attached that locks both piston members and causes both piston members to integrally slide up and down when the distance between the pair of piston members becomes equal to or less than a predetermined distance. Double pipette.