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WO2002099410A1 - Capteur et procede d'indication de la consommation d'oxygene - Google Patents

Capteur et procede d'indication de la consommation d'oxygene Download PDF

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Publication number
WO2002099410A1
WO2002099410A1 PCT/US2002/017923 US0217923W WO02099410A1 WO 2002099410 A1 WO2002099410 A1 WO 2002099410A1 US 0217923 W US0217923 W US 0217923W WO 02099410 A1 WO02099410 A1 WO 02099410A1
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WO
WIPO (PCT)
Prior art keywords
sample
electrodes
electrode
components
current
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2002/017923
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English (en)
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WO2002099410A9 (fr
Inventor
La Shaun Berrien
Gary Binyamin
Hilary S. Lackritz
Petr Vanysek
Mingqi Zhao
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Monogram Biosciences Inc
Original Assignee
Aclara Biosciences Inc
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Filing date
Publication date
Application filed by Aclara Biosciences Inc filed Critical Aclara Biosciences Inc
Publication of WO2002099410A1 publication Critical patent/WO2002099410A1/fr
Anticipated expiration legal-status Critical
Publication of WO2002099410A9 publication Critical patent/WO2002099410A9/fr
Ceased legal-status Critical Current

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G01N27/403—Cells and electrode assemblies
    • G01N27/404—Cells with anode, cathode and cell electrolyte on the same side of a permeable membrane which separates them from the sample fluid, e.g. Clark-type oxygen sensors
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/18—Water
    • G01N33/1806—Biological oxygen demand [BOD] or chemical oxygen demand [COD]

Definitions

  • the present invention relates to a method for measuring the electrochemical oxygen demand in a liquid sample, and to devices useful in practicing the method.
  • Oxygen demand is an important parameter for assessing the concentration of organic/biological compounds or components in water resources and in industrial process streams. Because the degradation of organic compounds often requires oxygen, their concentrations can be estimated by the amount of oxygen required to degrade them to a known chemical state. When this oxidation is carried out chemically, the value obtained is called chemical oxygen demand (COD).
  • COD chemical oxygen demand
  • BOD Biochemical (or biological) oxygen demand (BOD) is its counterpart, cited when the process is carried out using biological entities such as microbes.
  • the conventional methods for COD and BOD determination involve tedious and time-consuming procedures. COD is preferred for estimating organic pollution, but its conventional evaluation methods have several disadvantages such as long analysis time, hazardous reagents that must be disposed of, and high probability of error due to complex procedures dependent upon operator skill.
  • Measurement is accomplished under conditions of electron transfer to or from the components or intermediary to or from the working electrode, an electrical circuit connecting this electrode to a the counter and possibly the reference electrode and having a power source for applying a voltage potential between the working and counter electrodes, and possibly a measurement circuit for measuring the potential between the working and reference electrodes.
  • Current flow between working and counter electrodes through the sample solution is sustained by electron donation/acceptance to/from one or more sample components or intermediaries at the counter electrode and by the oxidation/reduction of said one or more bio/organic components at the working electrode.
  • This support matrix may have a relatively high surface-to-volume ratio in order to provide rapid mixing and dissolution of said chemical reagents.
  • Said support matrix may serve the additional function of the filtration of large particulate material from the liquid sample prior to its entrance into the measurement chamber.
  • a separate particulate filter can also be located prior to the chemical reagent support material in some embodiments.
  • the methods and components above yield the ability to generate quantitative measurement results rapidly for electrochemical oxygen demand, chemical oxygen demand, and/or biological/biochemical oxygen demand.
  • the overall device operation and measurement time can total less than thirty minutes, or in other embodiments be as short as five to fifteen minutes.
  • results described below indicate that after 0.5 seconds, the measurement result from analyte oxidation is similar to results obtained at significantly longer times, but allowing the oxidation to continue improves the signal-to-noise ratio and hence the measurement reliablity.
  • Figures 2a and 2b show two parts of a microfluidics device constructed in accordance with one embodiment of the present invention
  • Figure 3 is an exploded view of a microfluidics device constructed in accordance with one embodiment of the present invention.
  • Figure 4 shows the linear curve of concentration versus measured COD value, collected on a commercial system;
  • Figure 7 shows EOD measured values and a similar sample measured on a commercial system
  • the circuit may include a power source 30 for applying a potential across the two electrodes; current flow in the sample can be sustained by electron donation or acceptance to one or more sample components at the second electrode and by the oxidation or reduction of one or more organic components at the first electrode.
  • a current response element 32 may be included in the device for measuring the current flow over a given time or the total charge during a collection period in theelectrochemical cell, related to the total oxidizable or reducible components contained in the sample.
  • the circuit may be fully integrated with the device and housed within substrate 24. Assembly of device 12 is accomplished by stacking the printed circuit board substrates with pressure sensitive adhesives 28 and 29 to form a sandwich-like structure. Alignment of the layers can be achieved using an alignment mark on the substrates to mark the positions of the pressure sensitive adhesives.
  • printed circuit boards 20 and 21 are used as the substrate for connections between the electrodes and the electronics subsystem. Traces consisting of 4 ⁇ m of Ni followed by 0.1 ⁇ m of Au are plated on the circuit boards according to the designated positions of the electrodes. Fluid input/output ports can be drilled through one substrate, such that the inlet port position allows for fluid contact with the electrode on the opposing surface and the outlet port position allows for ventilation of the chambers. The geometry of the drilled port may be compatible with a syringe for use in sample introduction. A recess can be machined in both halves of the boards to accommodate a 3V coin batter for power supply of all electronics. The connections between the electrodes and the electronics and all other inter-component connection may be formed via conductive traces on the circuit boards using standard industry techniques.
  • Assembly of the circuit boards follows standard industry techniques that include the use of solder paste to attach IC components to the circuit board with pre-plated traces.
  • the boards may then be processed in a reflow IR oven, cleaned and tested.
  • the volume of the electrochemical cell and the exposed electrode area may be important for reproducibility.
  • both of these parameters are defined by the thickness and the shape of the spacer, which is also used as an active bond between the two parts of the card, holding the opposing electrodes together.
  • the spacer may be 0.1 mm to 0.7 mm thick. In a preferred embodiment, the spacer is 0.5 mm thick.
  • the spacer may have a consistent thickness.
  • the pressure used for sealing may be well controlled. Higher pressure may render the spacer thinner. Also, higher pressure may compress and expand the spacer, which upon releasing the pressure will relax and rebound.
  • the device includes a stop alignment feature. The stop alignment feature prevents lateral expansion and contraction, described below, which can compromise the function of the device.
  • reaction chamber and sample preparation chamber with connecting channel are formed, via machining, embossing, cold forming or other method common in manufacturing technology, into the device substrate material to a specified depth for control of chamber volumes.
  • a hot melt adhesive or other material known to those skilled in the art may be used to bond the formed substrate to another substrate used to seal the device. Techniques such as thermal lamination, ultrasonic welding and other methods generally practiced in the art may be used to bond the device substrates.
  • the device has a multi-chamber design.
  • Two or more chambers may be advantageous for on-card addition of reagents to the sample, wherein a plurality of reagents for catalysis, conditioning, sensitizing, stability, etc. could be placed in compartments away from the electrodes.
  • a plurality of reagents for catalysis, conditioning, sensitizing, stability, etc. could be placed in compartments away from the electrodes.
  • reagents for catalysis, conditioning, sensitizing, stability, etc. could be placed in compartments away from the electrodes.
  • via 26 or via 28, or both can contain immobilized microorganisms or enzymes that can degrade the organic analytes. Thereafter, the products of the predigestion can be introduced into said chambers.
  • the electrodes are screen printed onto the printed circuit boards over plated conductive traces described previously.
  • the electrodes can detect organic compounds in the liquid sample.
  • the electrodes may be flexible and modified to have the desired composition, resistance, and geometry, which is standard in the art.
  • One or more integrated electrocatalysts may be provided on the electrode surface to catalyze the oxidation or reduction of organic compounds in the solution.
  • the catalyst is a metal oxide.
  • the metal oxide may be selected from the group consisting of Cu 2 O, CuO, PbO 2 , RuO 2 , SnO 2 , PbO 2 , NiO, and TiO 2 .
  • the catalyst is a metal or metal oxide alloy. In yet another embodiment, the catalyst is a metal complex.
  • the catalyst can be added to the working electrode by conductive ink in a controlled manner known to those of skill in the art.
  • the reference electrode or counter electrode or both can be Ag/AgCI, Pt, Au, or other material known to those skilled in the art.
  • the electrode layout can be designed to maximize the consumption or reaction time of organic compounds in the solution. The electrode layout can also be designed to yield the desired signal level.
  • the device in the preferred embodiment consists of a three electrode sandwich-structure device 50. Two substrates 52 and 54 sandwich the device 50.
  • the electrodes may use conductive ink or conductive ink composites as the working electrode 56, reference electrode 58, and/or counter electrode 60.
  • the electrodes have conductive traces 64 and 65 in contact with the electrodes. Alternatively, the electrodes do not have conductive traces underneath.
  • Figures 2a and 2b show two parts 70 and 72 of the device 50 following assembly.
  • the electrodes can be manually or automatically printed onto a plastic substrate for catalyst screening. Insulated wires can then be attached to the electrodes and cured. Holes can then be drilled through the counter electrode. D. Electrode Coating
  • the electrodes do not have a coating, as described in Example 2.
  • the electrodes are provided with an electrode coating.
  • the electrode coating is a permeation layer that provides spacing between the electrode surface and the liquid sample and allows solvent molecules, small counter-ions, and electrolysis reaction gases to freely pass to and from the electrode surface. It is possible to include within the permeation layer substances which can reduce the adverse physical and chemical effects of electrolysis reactions, including, but not limited to, iron complexes for O 2 and peroxides.
  • the thickness of the electrode coating can range from approximately 1 nm to 100 ⁇ m, with 2 nm to 10 ⁇ m being the most preferred. Electrode coating permeation layers are discussed in U.S. Patent No. 6,238,624, which is incorporated herein by reference in its entirety.
  • the purpose of the said coating layer can be to prevent or minimize electrode fouling.
  • the electronic subsystem may consist of a potentiostat, an integration circuit, a microprocessor, a thermistor and a output display element.
  • the function of the potentiostat is to maintain a constant potential across the electrochemical cell.
  • the integration circuit builds up charge from current flow through the electrochemical cell onto a capacitor, which is then discharged and reset by the microprocessor after a specified voltage across the capacitor is reached.
  • the microprocessor also counts the number of discharge/reset cycles and sums them to determine the total charge.
  • the indicator can be based on colorimetric methods.
  • the electrochemically generated current after amplification in a current amplifier, can be routed through a wedge-shaped resistive foil heater. As the resistance of the heater varies with distance, the most resistive tip of the wedge will heat to higher temperature than the wider end.
  • a heat sensitive dye strip may be placed on top of the heater. Upon temperature increase to a certain value the color of the dye changes; the higher the current, the farther on the wedge heater the temperature will reach the dye color trigger point. Thus, current in the system will be proportional to the length of the discolored dye strip.
  • the window denudation will result in appearance change from that of a shiny mirror surface to a dull and dark color of the material inside the electrochemical charge measuring electrochemical reaction cell.
  • the indicator connected with the amplifier directly gives out the level of the COD or BOD in the solution.
  • the final data may be given in numbers or as levels, such as "very good”, “moderately clean,” “polluted,” or “very polluted.”
  • fluid delivery to the reaction and sample preparation chambers can be achieved via more novel methods using wicking and capillary action, diaphragm mechanism or other positive displacement pumping mechanism.
  • the electrochemical cell and the electronics subsystems and output display elements are separate entities.
  • the material substrates, reaction and sample preparation chambers and electrodes with conductive lead make up a single disposable device.
  • a semi-permanent handheld device houses the electronics and output display elements. These devices can be integrated into a single sensor device for the measurement of EOD, COD or BOD. Each disposable electrochemical cell would perform a single or single set of measurements and be discarded while the handheld electronic device would be used for analysis of numerous cells.
  • the invention includes a method for measuring the electrochemical, chemical, or biological oxygen demand in a liquid sample.
  • the first step of the method involves adding the sample to the reaction chamber to fill the reaction chamber in the device with the sample.
  • the sample is injected, via syringe, into the reaction chamber through the inlet port and air is expelled through the outlet.
  • a syringe may be used to introduce the liquid sample into the sample preparation chamber or reaction chamber via channel 26 or channel 28, and air is thus expelled out through channel 26 or channel 28.
  • the syringe incorporates a means for pH adjustment and filtration of the sample. Alternatively, means for sample pH adjustment and filtration are incorporated into device 12.
  • sample is introduced into the cell and possibly mixed with previously deposited reagents using a lateral flow membrane and wicking through the matrix.
  • filters can be made out of a variety of materials which are stable in the presence of the needed reaction reagents and known to people skilled in the art.
  • the cell is designed such that liquid is introduced into the cell via capillary action without the aid of a filter, having cell dimensions, channel dimensions, and possibly surface treatments known to those skilled in the art.
  • sample results may be obtained between 10 and 20 minutes. In yet another preferred embodiment, sample results may be obtained in less than 15 minutes.
  • the range of the detection can be from 10 to 15,000 ppm. In one embodiment, the range of detection is from 10 to 15,000 ppm. In another embodiment, the range of detection is between 10 and 3,000 ppm.
  • the electrode-containing cell may be disposed of, with the residing sample, when the measurements are complete while retaining the electronics component "handle".
  • the electrode-containing cell is incorporated into a system containing integrated electrodes, all of which, including the residing sample, would be disposed of when the measurements are complete.
  • an enzyme, or mixture of enzymes may be used, either in free solution or immobilized in channels (via beads, patches, sol-gels, hydrogels, etc known to those skilled in the art).
  • the enzyme system would be capable of converting (through a variety of well-known reactions including, e.g. oxidation, reduction, hydrolysis, etc.) some or all analytes in solution from non-electroactive or analytes in solution with little electroactivity into electroactive species making the device more sensitive and capable of indicating more analytes.
  • a microorganism, or mixture of microorganisms in a variety of states, e.g. active, inactive, killed, lyophilized, dormant, or the like, either in free solution or immobilized in channels, e.g. via beads, patches, sol-gels, hydrogels, etc. as is known to those skilled in the art.
  • the microorganism system would be capable of converting completely or partially, e.g. through digestion, some or all analytes in solution from non-electroactive analytes or analytes with little electroactivity into electroactive species making the device more sensitive and capable of detecting more analytes.
  • An additional embodiment allows for a partitioning of an analyte from an aqueous phase to an organic liquid or organic solid phase containing electrolyte and previously described electrodes.
  • the aprotic solvent allows for an increased potential window during electrochemical measurements, alleviating possible interference of water oxidation in aqueous solvent and the ability to oxidize a broader list of analytes.
  • Yet another embodiment allows for the generation in situ of oxidizing reagents for the chemical oxidation of analytes in solution.
  • the appropriate reactants would be in solution and species such as, but not limited to, hypochlorous acid or ozone can be generated electrochemically and then go on to react with organic analytes in solution.
  • Results obtained with the SP2 device described below were compared to COD results obtained with the commercial Orbeco-Hellige 975MP spectrophotometer in combination with the Accu-test EPA approved micro-COD reagent vials, both purchased from Bioscience, Inc. (Bethlehem, PA).
  • the sample consisted of a mixture of glucose, sucrose, glycerol, glycine, and EDA.
  • Figure 4 shows the linear curve of concentration versus measured COD value, collected on the Bioscience system. Briefly, 2.5mL of sample was added to the commercially available reagent tubes and incubated at 150°C for 2 hours. The COD value of the sample was then measured on the appropriately calibrated Orbeco-Hellige reader.
  • Figure 5 shows a linear concentration versus peak current value.
  • the currents reported are the peak currents obtained during a cyclic voltammogram for the sample in a SP2 cell.
  • the peak current is the maximum current obtained during a potential sweep of the sample in contact with said electrodes and is a common electrochemical technique.
  • the measured COD data is related to the peak current.
  • the graph shows a linear correlation between the measured, EPA- approved COD value and the EOD measurement.
  • a generation of electrochemical cells was prepared. All the cards used were prepared in the same controlled manner to give validity to the further statistical treatment needed to obtain calibration curves.
  • the working electrode was screen printed carbon ink containing an electrooxidation catalyst which is an active catalytic material.
  • Both the counter and reference electrodes were screen printed strips of silver/silver chloride, a material well suited both for making conductive paths and as a steady potential reference electrode.
  • the working electrode and counter/reference pair were printed on different circuit board pieces and assembled facing each other, separated by a defined spacer. This spacer determines the volume of liquid, which is in immediate contact with the electrodes. The shape of the spacer is the "snowman" design.
  • the purpose of the algorithm is to find an "average" function that converts the measured charge to a value of COD. Because the sensitivities for different compounds are not exactly the same and the experimental data have a degree of scatter, an exact relationship for the conversion is not possible. Instead, a calibration curve is calculated that fulfills the following conditions: (a) it is a monotonic function; and (b) the sum of errors for all points, measured as their distance from the calibration curve, is minimal. Several minimization approaches can be used; however, minimization of weighted sum of squares of the errors was selected for the final calibration. The curve to which the data points were fit was a second order polynomial. The analytical form of the line is:
  • C cod 5.31 x 10 5 Q 2 + 1.13 x 10 4 Q - 14.095
  • C ⁇ d is the calculated concentration in units of ppm COD
  • Q is the measured charge that has passed through the cell under the standard experimental conditions. The conditions in this test were applied potential 0.5 V Ag/AgCI and duration 300 sec (5 minutes).
  • FIG. 8 shows the charge v. concentration curves at various short times up to 0.5 seconds up to lOOOppm sample.
  • Fig. 9 shows the comparison of short time periods to the established five- minute test.
  • galvanostatic oxidation can yield desired dynamic ranges similar to the chronoamperometric methods, forcing a current through the cell while monitoring potential until a titration point is reached.
  • the titration point represents the exhaustion of one analyte, the sample, to an analyte with a higher oxidation potential, in this case water. The point is the time at which the analyte in solution is exhausted and to maintain current values a species with higher potential must be oxidized. It is commonly called the electrochemical titration point (shown in green in Fig. 12 for 10OOppm glucose). Lower concentrations of glucose which had been exhausted earlier in the measurement come to a similar potential value for the desired current flow near the oxidation point of aqueous solutions.

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Abstract

L'invention a trait à un capteur servant à mesurer la consommation d'un échantillon en oxygène électrochimique, chimique ou biologique. Ledit capteur comprend une chambre de mesure (14) ayant au moins une dimension de chambre inférieure à un millimètre. Il comprend également une électrode de travail (56) et une contre-électrode (60), et éventuellement une électrode de référence (58) conçue pour être en contact électrique avec le liquide contenu dans la chambre. La mesure est réalisée dans des conditions de transfert d'électrons vers les composants ou à partir d'eux, ou vers l'électrode de travail ou à partir d'elle, un circuit électrique connectant ladite électrode à la contre-électrode (60) et éventuellement à l'électrode de référence (58) et disposant d'une source d'énergie permettant d'appliquer un potentiel entre l'électrode de travail et la contre-électrode, et éventuellement entre l'électrode de travail et l'électrode de référence. Le circuit comprend un dispositif dépendant du courant qui permet de mesurer le courant électrique instantané ou moyenné dans le temps ou d'intégrer la charge circulant à travers le circuit sur une période de temps donnée, le courant ou la charge étant reliés à la totalité des composants bio/organiques oxydables ou réductibles contenus dans l'échantillon avec la chambre de mesure.
PCT/US2002/017923 2001-06-04 2002-06-04 Capteur et procede d'indication de la consommation d'oxygene Ceased WO2002099410A1 (fr)

Applications Claiming Priority (2)

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US29590801P 2001-06-04 2001-06-04
US60/295,908 2001-06-04

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WO2002099410A9 WO2002099410A9 (fr) 2004-04-15

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1611440A4 (fr) * 2003-04-04 2008-10-29 Aqua Diagnostic Pty Ltd Determination photoelectrochimique de la demande chimique en oxygene
US7666285B1 (en) * 2004-02-06 2010-02-23 University Of Central Florida Research Foundation, Inc. Portable water quality monitoring system
WO2011156854A1 (fr) * 2010-06-17 2011-12-22 Geneasys Pty Ltd Dispositif microfluidique doté d'un capteur de conductivité
US20150108009A1 (en) * 2013-10-23 2015-04-23 Hach Company Apparatus, composition and method for determination of chemical oxidation demand
WO2021163386A1 (fr) * 2020-02-11 2021-08-19 Massachusetts Institute Of Technology Dispositifs et procédés de détermination de niveaux de phosphate dans l'eau naturelle
CN116626122A (zh) * 2023-05-29 2023-08-22 重庆理工大学 水体化学需氧量的检测传感器及检测方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3676321A (en) * 1970-07-27 1972-07-11 Honeywell Inc Electrochemical oxygen demand system
US4426451A (en) * 1981-01-28 1984-01-17 Eastman Kodak Company Multi-zoned reaction vessel having pressure-actuatable control means between zones
EP0282441A2 (fr) * 1987-03-09 1988-09-14 Ulrich Dr.-Ing. Pilz Procédé de détermination de la demande chimique en oxygène de l'eau
US5426042A (en) * 1991-11-22 1995-06-20 Nakano Vinegar Co., Ltd. Klebsella oxytoca ferm BP-I/3616 and immobilization thereof with a gelating agent in pores of a membrane
US5726565A (en) * 1992-10-28 1998-03-10 Nakano Vinegar Co., Ltd. Coulometric analysis method and a device therefor
US6113762A (en) * 1995-02-22 2000-09-05 Isao Karube Microbial electrode and microbial sensor

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3676321A (en) * 1970-07-27 1972-07-11 Honeywell Inc Electrochemical oxygen demand system
US4426451A (en) * 1981-01-28 1984-01-17 Eastman Kodak Company Multi-zoned reaction vessel having pressure-actuatable control means between zones
EP0282441A2 (fr) * 1987-03-09 1988-09-14 Ulrich Dr.-Ing. Pilz Procédé de détermination de la demande chimique en oxygène de l'eau
US5426042A (en) * 1991-11-22 1995-06-20 Nakano Vinegar Co., Ltd. Klebsella oxytoca ferm BP-I/3616 and immobilization thereof with a gelating agent in pores of a membrane
US5726565A (en) * 1992-10-28 1998-03-10 Nakano Vinegar Co., Ltd. Coulometric analysis method and a device therefor
US6113762A (en) * 1995-02-22 2000-09-05 Isao Karube Microbial electrode and microbial sensor

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1611440A4 (fr) * 2003-04-04 2008-10-29 Aqua Diagnostic Pty Ltd Determination photoelectrochimique de la demande chimique en oxygene
US7666285B1 (en) * 2004-02-06 2010-02-23 University Of Central Florida Research Foundation, Inc. Portable water quality monitoring system
US8057724B2 (en) 2004-02-06 2011-11-15 University Of Central Florida Research Foundation, Inc. Portable water quality sensor fabrication method
WO2011156854A1 (fr) * 2010-06-17 2011-12-22 Geneasys Pty Ltd Dispositif microfluidique doté d'un capteur de conductivité
US20150108009A1 (en) * 2013-10-23 2015-04-23 Hach Company Apparatus, composition and method for determination of chemical oxidation demand
US10302552B2 (en) * 2013-10-23 2019-05-28 Hach Company Apparatus, composition and method for determination of chemical oxidation demand
WO2021163386A1 (fr) * 2020-02-11 2021-08-19 Massachusetts Institute Of Technology Dispositifs et procédés de détermination de niveaux de phosphate dans l'eau naturelle
CN116626122A (zh) * 2023-05-29 2023-08-22 重庆理工大学 水体化学需氧量的检测传感器及检测方法

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