CN110044982B

CN110044982B - Preparation method of porous membrane layer, electrochemical sensor and preparation method of electrochemical sensor

Info

Publication number: CN110044982B
Application number: CN201910287083.XA
Authority: CN
Inventors: 周连群; 李金泽; 张芷齐; 李传宇; 姚佳; 张威; 郭振
Original assignee: Suzhou Institute of Biomedical Engineering and Technology of CAS
Current assignee: Suzhou Institute of Biomedical Engineering and Technology of CAS
Priority date: 2019-04-10
Filing date: 2019-04-10
Publication date: 2022-04-29
Anticipated expiration: 2039-04-10
Also published as: CN110044982A

Abstract

The invention discloses a preparation method of a porous membrane layer, which comprises the step of placing a precursor solution in a closed reaction chamber to gelatinize the precursor solution so as to obtain porous gel. According to the preparation method, the sol solution is gelatinized in the closed reaction chamber, so that the collapse of the pores of the gel can be avoided, and the porous film layer with uniform pores and high porosity can be obtained. The invention discloses an electrochemical sensor which comprises a first electrode array and a second electrode array, wherein the first electrode array and the second electrode array share a first reference electrode, and the outer side surfaces of the first reference electrode and an enzyme electrode are coated with a hydrophobic porous membrane. The electrochemical sensor is high in integration level, the two electrode arrays share the first reference electrode, and the first reference electrode can be arranged in the same detection channel, so that the electrode structure of the sensor is simplified. The invention discloses a preparation method of the electrochemical sensor, which has the advantages of simplified preparation process and high preparation efficiency.

Description

Preparation method of porous membrane layer, electrochemical sensor and preparation method of electrochemical sensor

Technical Field

The invention relates to the technical field of electrochemical detection, in particular to a preparation method of a porous membrane layer, an electrochemical sensor and a preparation method of the electrochemical sensor.

Background

Point Of Care Testing (POCT), also known as Point Of bed Testing, is a new field Of medical Testing technology development. The POCT saves the complex processing procedure of laboratory inspection, can be carried out on the sampling site, and can quickly obtain the detection result by utilizing a portable analysis instrument and a matched reagent. POCT does not need fixed places, and is suitable for different application scenes such as emergency rooms, outpatients, patient beds, accident sites, fields and the like; the system can obviously shorten the inspection period, diagnose and treat patients in time, and has huge application space in the aspects of field first aid, hospital emergency treatment, chronic disease prevention and treatment, family monitoring and the like.

The development of instant detection depends on a portable small-sized detection instrument capable of realizing rapid detection, and the electrochemical sensor has higher occupation ratio and faster development speed in the POCT field due to the advantages of simple equipment, high sensitivity and specificity and low cost. The membrane electrode such as an ion selective electrode, an enzyme electrode, an immunity electrode and the like is used as an electrochemical sensor electrode, and can realize the detection of different indexes such as blood gas, blood biochemical substances, blood electrolyte, pregnancy, disease markers and the like. The membrane electrode has a porous membrane layer structure and is used as a surface modification layer or an electrolyte layer of the electrode. The sol-gel method is suitable for forming a gel network structure by various materials due to strong controllability and rich sol-gel systems, and is commonly used for preparing a porous membrane layer with a certain pore structure. However, in the reaction process of sol solution gelation, the increase of the internal surface tension of the gel due to the volatilization of the solvent causes the cracking of the gel network, the collapse of the pore structure of the gel, the reduction of the porosity and the specific surface area, the reduction of the mechanical property and the electrical property of the porous membrane layer and the influence on the normal use of the membrane electrode. In order to maintain the pore structure of the porous membrane layer, a pore-forming agent is usually added into the sol solution, so that the system components of the sol solution are complex, and the optimal adjustment of the component ratio in the sol solution is not facilitated.

Disclosure of Invention

Therefore, the technical problem to be solved by the invention is to overcome the defects that the gel structure is easy to crack, the pores of the gel collapse and the porosity is reduced in the preparation process of the porous membrane layer in the prior art.

Therefore, the invention provides the following technical scheme:

in a first aspect, the present invention provides a method for preparing a porous membrane layer, comprising the steps of:

(1) preparing a sol solution, wherein the sol solution is a precursor solution of a solid electrolyte layer or a hydrophobic porous membrane; (2) placing the precursor solution in a closed reaction chamber, and gelatinizing the precursor solution to obtain porous gel; (3) and drying the porous gel to obtain the porous membrane layer.

Preferably, the above preparation method, wherein the step (3) comprises: forming an opening communicated with the outside in the reaction chamber, and then carrying out drying treatment on the porous gel in the reaction chamber;

preferably, before the drying treatment, the method further comprises a step of purifying the porous hydrogel.

Preferably, the above preparation method, wherein the step (1) comprises:

mixing graphene oxide with vitamin C in water to make the graphene oxide: vitamin C: the mass ratio of water is (10-5): (1-5): (90-95) obtaining a graphene sol solution, wherein the graphene sol solution is a precursor solution of the solid electrolyte layer; or,

mixing aniline with ammonium persulfate in water to make the aniline: ammonium persulfate: the mass ratio of water is (10-5): (1-5): (90-95) obtaining a polyaniline sol solution, wherein the polyaniline sol solution is a precursor solution of the solid electrolyte layer; or,

mixing pyrrole with ferric chloride in water such that the ratio of pyrrole: ferric chloride: the mass ratio of water is (10-5): (1-5): (90-95) obtaining a polypyrrole sol solution, wherein the polypyrrole sol solution is a precursor solution of the solid electrolyte layer; or,

mixing a photoinitiator with polydimethylsiloxane in a first solvent such that the photoinitiator: polydimethylsiloxane: the mass ratio of the first solvent is (0.5-2): (10-20): (70-90) obtaining a polydimethylsiloxane sol solution, wherein the polydimethylsiloxane sol solution is a precursor solution of the hydrophobic porous membrane; or,

mixing polyvinylidene fluoride, a second solvent and a third solvent to make the polyvinylidene fluoride: a second solvent: the mass ratio of the third solvent is (5-10): (70-80): (5-20) obtaining a polyvinylidene fluoride sol solution, wherein the polyvinylidene fluoride sol solution is a precursor solution of the hydrophobic porous membrane; or,

mixing a cellulose triacetate polymer, a fourth solvent, and a fifth solvent such that the cellulose triacetate polymer: a fourth solvent: the mass ratio of the fifth solvent is (5-10): (70-80): (5-20) obtaining a sol solution of cellulose triacetate polymer, wherein the sol solution of cellulose triacetate polymer is a precursor solution of the hydrophobic porous membrane;

preferably, the first solvent is selected from toluene or cyclohexanone, the second solvent is selected from N, N-dimethylformamide or acetic acid, the third solvent is selected from dimethylacetamide or formic acid, the fourth solvent is selected from N, N-dimethylformamide or ethyl acetate, and the fifth solvent is selected from dimethylacetamide or chloroform.

Further preferably, in the preparation method, the reaction temperature for gelation of the graphene sol solution is 15-70 ℃, and the reaction time is 0.5-2 h; the reaction temperature of the polyaniline sol solution gelation is 0-4 ℃, and the reaction time is 0.5-1 h; the reaction temperature of the gelation of the polypyrrole sol solution is 0-4 ℃, and the reaction time is 0.5-1 h;

the sol solution of the polydimethylsiloxane is irradiated for 5-100 seconds by ultraviolet light to carry out a gelation reaction; heating the polyvinylidene fluoride sol solution to 75-90 ℃, then cooling to 20-30 ℃, and carrying out a gelation reaction; the sol solution of cellulose triacetate polymer is heated to 75-90 ℃, and then cooled to 20-30 ℃ to carry out gelation reaction.

Preferably, in the above preparation method, the purification treatment comprises: replacing the solvent of the porous gel with deionized water; the drying treatment is selected from one of atmospheric drying, freeze drying and supercritical drying.

In a second aspect, the invention provides an electrochemical sensor electrode, which comprises a porous membrane layer prepared by the preparation method, wherein the porous membrane layer is a solid electrolyte layer or a hydrophobic porous membrane of the electrochemical sensor electrode.

In a third aspect, the present invention provides an electrochemical sensor comprising:

the first electrode array is provided with at least one enzyme electrode and counter electrodes which are arranged in one-to-one correspondence with the enzyme electrodes;

a second electrode array having at least one ion measuring electrode;

the first electrode array and the second electrode array share a first reference electrode, the outer side surfaces of the first reference electrode and the enzyme electrode are coated with a hydrophobic porous membrane, and the hydrophobic porous membrane is a porous membrane layer prepared by the method of any one of claims 1 to 5.

Preferably, in the electrochemical sensor, the enzyme electrode includes an electrode substrate layer and an oxidase layer which are stacked, and the hydrophobic porous membrane is coated on the outer surface of the enzyme electrode; the ion measuring electrode comprises an electrode substrate layer, a solid electrolyte layer and an ion selective membrane, wherein the electrode substrate layer and the solid electrolyte layer are arranged in a stacked mode, and the ion selective membrane is coated on the outer surface of the ion measuring electrode; the first reference electrode comprises an electrode substrate layer and a reference electrolyte layer which are arranged in a stacked mode, and the hydrophobic porous membrane is coated on the outer surface of the first reference electrode; the solid electrolyte layer is a porous membrane layer prepared by the method;

preferably, the enzyme electrode is selected from at least one of a glucose oxidase electrode and a lactate oxidase electrode, and the oxidase layer is selected from at least one of a glucose oxidase layer and a lactate oxidase layer; the ion measuring electrode is selected from at least one of a calcium ion electrode, a potassium ion electrode, a sodium ion electrode, and a chloride ion electrode, and the ion selective membrane is selected from at least one of a calcium ion selective membrane, a potassium ion selective membrane, a sodium ion selective membrane, and a chloride ion selective membrane.

Preferably, the electrochemical sensor further comprises a third electrode array and/or a fourth electrode array sharing the first reference electrode, the third electrode array comprises a pH electrode, and the fourth electrode array comprises a hematocrit electrode;

preferably, the third electrode array further comprises O₂Electrode with said O₂A counter electrode corresponding to the electrode; and/or the third electrode array further comprises CO₂Electrode, with said CO₂A second reference electrode corresponding to the electrode;

preferably, the pH electrode comprises an electrode substrate layer and a solid electrolyte layer which are arranged in a stacked manner, and a hydrogen ion selective membrane coated on the outer surface of the pH electrode.

Preferably, said O is₂The electrode comprises an electrode base layer and an electrode O₂An electrolyte layer and coating the O₂O of the outer surface of the electrode₂A gas permeable membrane; the CO is₂The electrode comprises an electrode basal layer and a solid electrolyte layer which are arranged in a laminated manner, and the electrode is sequentially coated with the CO₂Hydrogen ion selective membrane and CO on the outer surface of the electrode₂A gas permeable membrane; the second reference electrode comprises an electrode substrate layer and a reference electrolyte layer which are arranged in a stacked mode, and a hydrophobic breathable film and CO which are sequentially coated on the outer surface of the second reference electrode₂And (3) a breathable film.

In a fourth aspect, the present invention provides a method for preparing an electrochemical sensor, comprising: a first reference electrode, an enzyme electrode, an ion measuring electrode, and a counter electrode are prepared simultaneously on a substrate.

Preferably, the preparation method comprises the following steps:

s1, preparing at least 4 electrode base layers arranged at intervals on the substrate;

s2, preparing a solid electrolyte layer on at least 1 of the electrode base layers by the above method;

s3, preparing an oxidase layer on at least 1 of the electrode base layers; preparing a reference electrolyte layer on at least 1 of said electrode substrate layers; coating an ion selective membrane on the outer surface of the electrode for preparing the solid electrolyte layer to form the ion measuring electrode;

s4, coating the hydrophobic breathable film prepared by the method of any one of claims 1 to 5 on the outer surface of the electrode for preparing the oxidase layer to form the enzyme electrode; coating the outer surface of the electrode for preparing the reference electrolyte layer with the hydrophobic gas-permeable membrane prepared by the method of any one of claims 1 to 5 to form the first reference electrode; and at least 1 electrode substrate layer is remained on the substrate to form the counter electrode, so that the electrochemical sensor is obtained.

Further preferably, the preparation method comprises the following steps:

s1, preparing at least 9 electrode base layers arranged at intervals on the substrate;

s2, preparing solid electrolyte layers on the 4 electrode base layers;

s3, preparing a glucose oxidase layer and a lactate oxidase layer on the 2 electrode substrate layers respectively; preparing a reference electrolyte layer on at least 1 of said electrode substrate layers; respectively coating a chloride ion selective membrane, a calcium ion selective membrane, a potassium ion selective membrane and a sodium ion selective membrane on the outer surface of the electrode for preparing the solid electrolyte layer to form a chloride ion electrode, a calcium ion electrode, a potassium ion electrode and a sodium ion electrode;

s4, respectively coating hydrophobic breathable films on the outer surfaces of the electrodes for preparing the glucose oxidase layer and the lactate oxidase layer to form a glucose oxidase electrode and a lactate oxidase electrode; coating a hydrophobic breathable film on the outer surface of the electrode for preparing the reference electrolyte layer to form the first reference electrode; and at least 2 electrode substrate layers are remained on the substrate to form a counter electrode corresponding to the glucose oxidase electrode and the lactate oxidase electrode, so that the electrochemical sensor is obtained.

Preferably, the preparation method comprises the following steps:

s1, preparing 14 electrode base layers arranged at intervals on the substrate;

s2, preparing a solid electrolyte layer on at least 6 of the electrode base layers;

s3, preparing a glucose oxidase layer and a lactate oxidase layer on the 2 electrode substrate layers respectively; preparing a reference electrolyte layer on 2 of said electrode substrate layers; preparing 0 on 1 of the electrode base layers₂The electrolyte layer is formed by respectively coating a chloride ion selective membrane, a calcium ion selective membrane, a potassium ion selective membrane, a sodium ion selective membrane and a hydrogen ion selective membrane on the outer surface of the electrode for preparing the solid electrolyte layer to form 1 chloride ion electrode, 1 calcium ion electrode, 1 potassium ion electrode, 1 sodium ion electrode and 2 pH electrodes;

s4, respectively coating hydrophobic breathable films on the outer surfaces of the electrodes for preparing the glucose oxidase layer and the lactate oxidase layer to form a glucose oxidase electrode and a lactate oxidase electrode; in the preparation of said 0₂The outer surface of the electrode of the electrolyte layer is coated with 0 prepared by the method₂A gas permeable film of form 0₂An electrode; coating a hydrophobic breathable film on the outer surface of the electrode for preparing the reference electrolyte layer to form 2 first reference electrodes; coating the outer surface of any one of the first reference electrodes with CO prepared by the method₂A gas permeable membrane forming a second reference electrode; coating the CO on the outer surface of any pH electrode₂Gas permeable membrane to form CO₂An electrode; the rest 4 electrode basal layers on the substrate respectively correspond to the counter electrode of the glucose oxidase electrode, the counter electrode of the lactate oxidase electrode and the electrode 0₂A counter electrode of the electrode and a hematocrit electrode to obtain the electrochemical sensor.

The technical scheme of the invention has the following advantages:

1. the preparation method of the porous membrane layer provided by the invention comprises the following steps: (1) preparing a sol solution, wherein the sol solution is a precursor solution of a solid electrolyte layer or a hydrophobic porous membrane; (2) placing the precursor solution in a closed reaction chamber, and gelatinizing the precursor solution to obtain porous gel; (3) and drying the porous gel to obtain the porous membrane layer.

According to the preparation method of the porous membrane layer, the precursor solution is subjected to a gelation process in a closed environment, so that the problem that the surface tension of a gas-liquid interface is improved due to solvent volatilization in the gelation process of converting the precursor solution from a liquid state to a solid state is avoided, the problems of gel network cracking and pore collapse in the gelation process are effectively solved, and the porous gel with controllable morphology is obtained. And finally, drying the porous gel, and removing the solvent in the porous gel to obtain the porous membrane layer. The porous film layer prepared by the method has the advantages of high porosity, high specific surface area, good pore diameter uniformity of pores and the like, and is suitable for preparing the porous film layer with 5-1000 nm of macroporous and mesoporous structures. The preparation process of the porous film layer does not need to add a pore-foaming agent, reduces the system components of the sol solution and is beneficial to the optimization of the solution system proportion. The porous membrane layer can improve the stable potential as the solid electrolyte layer, and the high specific surface area of the porous membrane layer is beneficial to improving the capacitance performance of the electrode. In addition, the solid electrolyte layer is suitable for carrying bioactive substances such as protein and enzyme, and the high porosity of the porous membrane layer is beneficial to improving the carrying rate of biomolecules such as protein and enzyme and improving the detection performance. When the porous membrane layer is used as a hydrophobic porous membrane to cover the surface of the electrode, the porous structure with uniform structure and high porosity is beneficial to improving the transmission capability of target molecules, so that the influence capability of the membrane electrode is improved; due to the good controllability of the porous membrane layer, the interference of other molecules can be effectively reduced by setting the pore diameter of the hydrophobic porous membrane.

2. The preparation method of the porous membrane layer provided by the invention comprises the following steps (3): and forming an opening communicated with the outside in the reaction chamber, and then carrying out the drying treatment on the porous gel in the reaction chamber. Solvent components in the porous gel are discharged through the opening in the drying process, and the solvent components in the porous gel are uniformly removed by drying in the limited reaction chamber, so that the damage of the drying process to a gel network structure is effectively reduced. In the process of purifying the porous hydrogel, the ionic components in the porous hydrogel are removed through purification treatment, so that the electrical property and the anti-interference performance of the porous hydrogel are improved.

3. The preparation method provided by the invention provides a preparation system of the precursor solution of the solid electrolyte layer and gelation reaction conditions, the precursor solution of the solid electrolyte layer comprises a graphene sol solution, a polyaniline sol solution and a polypyrrole sol solution, and the potential stability and the capacitance performance of the solid electrolyte layer obtained by adopting the solution system and the gelation conditions are improved. The preparation method provided by the invention provides a preparation system of a precursor solution of the hydrophobic porous membrane and gelation reaction conditions, wherein the precursor solution of the hydrophobic porous membrane comprises a polydimethylsiloxane sol solution, a polyvinylidene fluoride sol solution and a cellulose triacetate polymer sol solution, and the transmission capability and anti-interference performance of target molecules are improved by adopting the hydrophobic porous membrane obtained by the solution system and the gelation conditions.

4. The present invention provides an electrochemical sensor comprising: the first electrode array is provided with at least one enzyme electrode and counter electrodes which are arranged in one-to-one correspondence with the enzyme electrodes; a second electrode array having at least one ion measuring electrode; the first electrode array and the second electrode array share a first reference electrode, the outer side surfaces of the first reference electrode and the enzyme electrode are coated with a hydrophobic porous membrane, and the hydrophobic porous membrane is a porous membrane layer prepared by the method.

The electrochemical sensor can react with a substance to be detected in blood and generate an electric signal by using the enzyme electrode in the first electrode array, and is used for detecting biochemical substance components such as glucose, lactic acid and the like in the blood; ca in blood can be treated by using the ion electrodes in the second electrode array²⁺、Na⁺、K⁺、Cl^－And (4) detecting plasma components. In the existing electrochemical sensor for blood multi-parameter integrated detection, because the reaction between enzyme and the object to be detected is easy to affect the detection of ion components, in order to avoid the interference between detection electrodes with different parameters, an enzyme electrode and ions need to be usedThe measuring electrodes are arranged in different detection channels. According to the electrochemical sensor provided by the invention, the hydrophobic porous membrane is coated on the outer surface of the enzyme electrode, so that the phenomenon that reaction liquid in the enzyme electrode diffuses outwards to influence the detection of the ion measuring electrode can be effectively avoided, the first electrode array and the second electrode array can be arranged in the same detection channel, the first electrode array and the second electrode array share the first reference electrode, and the structure and the manufacturing difficulty of the electrochemical sensor are effectively simplified. The hydrophobic porous membrane is prepared by the preparation method of the porous membrane layer, has high porosity, good pore diameter controllability and high transmission rate to target molecules, and can prevent a large amount of liquid from flowing into the electrode through pores and maintain the working environment in the enzyme electrode. The outer surface of the first reference electrode is coated with the hydrophobic porous membrane, so that the interference of environmental factors is reduced, and a stable reference potential is provided.

5. The solid electrolyte layer in the electrochemical sensor, the ion measuring electrode and the first reference electrode is the porous membrane layer prepared by the method provided by the invention, and the solid electrolyte layer has good performance of converting ion conduction into electron conduction, can provide stable potential, has high capacitance performance, and enables the electrode to have the advantages of high response speed, high stability, high signal-to-noise ratio and the like.

The electrochemical sensor also comprises a third electrode array and/or a fourth electrode array, and the pH and O in blood can be treated by using the third electrode array and/or the fourth electrode array₂、CO₂And the integration detection of different parameters such as hematocrit and the like, the integration level of the electrochemical sensor is high, various detection parameters can be obtained in the detection process of a blood sample, and the detection efficiency is effectively improved. Meanwhile, the third electrode array and/or the fourth electrode array can share the first reference electrode, so that the structure of the electrochemical sensor is simplified, and the manufacturing difficulty is reduced.

6. The preparation method of the electrochemical sensor provided by the invention comprises the following steps: a first reference electrode, an enzyme electrode, an ion measuring electrode, and a counter electrode are prepared simultaneously on a substrate. The synchronous preparation process of the electrochemical sensor effectively simplifies the preparation steps of the electrochemical sensor integrated by multiple parameters and has high preparation efficiency.

In the above-mentioned production method, the production process in each step of S1 to S4 may be performed by the same production process, the electrode base layer in the step of S1 may be performed by a screen printing process, the solid electrolyte layer in the step of S2 may be performed by a production method of a porous membrane layer, the oxidase layer, the reference electrolyte layer, and the ion-selective membrane in the step of S3 may be performed by a screen printing process, and the hydrophobic gas-permeable membrane in the step of S4 may be performed by a production method of a porous membrane layer. By optimizing the preparation sequence and the preparation process of each electrode functional layer of the electrochemical sensor, the preparation process of the electrochemical sensor for detecting various parameters can be completed only by 4 operation steps, and the preparation process of the electrochemical sensor integrated by multiple parameters is effectively simplified.

Further, 0 in step S4₂Breathable film and CO₂The gas-permeable membrane adopts the same preparation method of the porous membrane layer, so that the integrated detection of the blood gas (pH, 0)₂、CO₂) Blood ion (Ca)²⁺、Na⁺、K⁺、Cl^－) 10 parameters of hematogenous substance (glucose, lactic acid) and hematocrit can be integrated to form the electrochemical sensor through 4 steps of preparation process.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic structural diagram of a mold for manufacturing a porous membrane layer according to embodiment 1 of the present invention;

fig. 2 is a schematic structural diagram of a mold for manufacturing another porous membrane layer according to embodiment 1 of the present invention;

FIG. 3 is a schematic diagram of an electrode arrangement of an electrochemical sensor provided in example 14 of the present invention;

FIG. 4 is a schematic diagram showing an electrode structure of an electrochemical sensor provided in example 14 of the present invention;

FIG. 5 is a schematic diagram of an electrode arrangement of an electrochemical sensor provided in example 15 of the present invention;

FIG. 6 is a schematic view of an electrode structure of an electrochemical sensor provided in example 15 of the present invention;

FIG. 7 is a graph showing response time and potential stability of a pH electrode obtained by the method provided in example 2 in Experimental example 1 of the present invention;

FIG. 8 is a voltage-concentration standard curve of a pH electrode obtained by the method provided in example 2 in Experimental example 1 of the present invention;

FIG. 9 is a voltage-concentration standard curve of a pH electrode obtained in Experimental example 1 of the present invention by the method provided in comparative example 1; description of reference numerals:

1-mould, 11-preparation layer, 12-base layer, 111-cover plate, 112-groove layer;

2-an electrochemical sensor; 20-a first reference electrode, 21-a first electrode array, 22-a second electrode array, 23-a third electrode array, 24-a fourth electrode array;

211-glucose oxidase electrode, 212-lactate oxidase electrode, 213-first pair of electrodes, 214-second pair of electrodes; 221-sodium ion electrode, 222-potassium ion electrode, 223-calcium ion electrode, 224-chloride ion electrode; 231-pH electrode, 232-O2 electrode, 233-CO 2 electrode, 234-second reference electrode, 235-third counter electrode; 241-hematocrit electrode.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example 1

The present embodiment provides a mold 1 for manufacturing a porous membrane layer, as shown in fig. 1, including a preparation layer 11 and a substrate layer 12 which are stacked. One side of the preparation layer 11 facing the substrate layer 12 is recessed inwards to form a pattern groove for preparing the porous film layer, and one side of the preparation layer 11 facing away from the substrate layer 12 is provided with at least one injection port for sol solution, and the injection port is communicated with the pattern groove. The pattern grooves in the preparation layer 11 are formed by Micro Electro Mechanical Systems (MEMS) or numerically controlled precision machining (CNC) and other methods. After the preparation layer 11 is obtained, the contact surfaces of the preparation layer 11 and the substrate layer 12 are respectively subjected to surface treatment, then the preparation layer 11 is bonded on the substrate layer 12, and the pattern groove in the preparation layer 11 is used as a reaction chamber for preparing the porous membrane layer, so that the manufacturing mold 1 of the porous membrane layer is obtained. The surface treatment method includes but is not limited to: surface treatment plasma etching, ion beam etching, chemical agent treatment, vapor deposition, sputtering, anodic oxidation, and the like. The material for forming the preparation layer 11 is selected from phase-change paraffin, polydimethylsiloxane, acrylate polymer, polyurethane and the like. The material forming the substrate layer 12 is selected from plastic, glass, ceramic, silicon, metal, etc. The base layer 12 may be an electrode base layer, and a porous film layer prepared on the electrode base layer may be directly formed by the manufacturing mold 1.

As an alternative embodiment, as shown in fig. 2, the preparation layer 11 is composed of a trench layer 112 and a cover plate 111 covering a side of the trench layer 112 away from the substrate layer, wherein a pattern groove for preparing the porous film layer is formed in the trench layer 112, and the cover plate 111 is bonded to a side of the trench layer 112 away from the substrate layer 12 by a double-sided tape or the like.

Example 2

The embodiment also provides a preparation method of the porous membrane layer, wherein the porous membrane layer is prepared by using the mold 1 of the embodiment 1, and the preparation method specifically comprises the following steps:

(1) taking 1mL of graphene oxide aqueous solution (5mg/mL), adding 1mg of vitamin C into the aqueous solution, and fully dissolving the vitamin C to obtain a graphene sol solution;

(2) injecting the graphene sol solution into the pattern groove through a sample inlet of the mold 1, and then sealing the sample inlet to form a closed reaction chamber; placing the mold 1 in a water bath, and keeping the temperature at 50 ℃ for 2h to obtain graphene porous gel;

(3) opening the sealed sample inlet to enable the reaction chamber to form an opening communicated with the outside, and performing solvent replacement on the graphene porous gel for 6-9 times by using deionized water through the sample inlet to obtain purified graphene porous gel; and (3) freeze-drying the graphene porous gel to obtain the porous membrane layer.

Example 3

This example provides a method for preparing a porous membrane layer, which differs from the preparation method provided in example 2 in that:

in the step (1), 1mL of graphene oxide aqueous solution (10mg/mL) is taken, 5mg of vitamin C is added into the aqueous solution, and the graphene sol solution is obtained after the vitamin C is fully dissolved; in the step (2), the mold 1 is placed in a water bath and kept at the temperature of 70 ℃ for 0.5h to obtain the graphene porous gel.

Example 4

in the step (1), aniline and ammonium persulfate are added into water, so that the mass ratio of aniline to ammonium persulfate to water is 10: 1: 95, fully dissolving to obtain polyaniline sol solution; in the step (2), the mould 1 is placed in a water bath and kept at the temperature of 4 ℃ for 0.5h to obtain the polyaniline porous gel.

Example 5

in the step (1), aniline and ammonium persulfate are added into water, so that the mass ratio of aniline to ammonium persulfate to water is 5: 5: 90, fully dissolving to obtain polyaniline sol solution; in the step (2), the mould 1 is placed in a water bath and kept at the temperature of 0 ℃ for 1h to obtain the polyaniline porous gel.

Example 6

in the step (1), pyrrole and ferric trichloride are added into water, so that the mass ratio of the pyrrole to the ferric trichloride to the water is 10: 5: 95, fully dissolving to obtain polypyrrole sol solution; in the step (2), the mould 1 is placed in a water bath and kept at the temperature of 0 ℃ for 1h to obtain the polypyrrole porous gel.

Example 7

in the step (1), pyrrole and ferric trichloride are added into water, so that the mass ratio of the pyrrole to the ferric trichloride to the water is 5: 1: 90, fully dissolving to obtain polyaniline sol solution; in the step (2), the mould 1 is placed in a water bath and kept at the temperature of 4 ℃ for 0.5h to obtain the polypyrrole porous gel.

Example 8

in step (1), a photoinitiator (e.g., 2, 4, 6 (trimethylbenzoyl) diphenylphosphine oxide) is mixed with polydimethylsiloxane in toluene so that the ratio of the photoinitiator: polydimethylsiloxane: the mass ratio of toluene is 0.5: 20: 70, uniformly mixing the solution to obtain a polydimethylsiloxane sol solution; in the step (2), the polydimethylsiloxane sol solution in the mold 1 is irradiated by ultraviolet light for 100s to obtain polydimethylsiloxane porous gel.

Example 9

in step (1), a photoinitiator (e.g., 2, 4, 6 (trimethylbenzoyl) diphenylphosphine oxide) is mixed with polydimethylsiloxane in toluene so that the ratio of the photoinitiator: polydimethylsiloxane: the mass ratio of toluene is 2: 10: 90, uniformly mixing the solution to obtain a polydimethylsiloxane sol solution; in the step (2), the polydimethylsiloxane sol solution in the mold 1 is irradiated by ultraviolet light for 5s to obtain the polydimethylsiloxane porous gel.

Example 10

in the step (1), polyvinylidene fluoride, acetic acid and Dimethylacetamide (DMAC) are mixed so that polyvinylidene fluoride: acetic acid: the mass ratio of the dimethylacetamide is 10: 80: 20, uniformly mixing the solution to obtain a polyvinylidene fluoride sol solution; in the step (2), heating the polyvinylidene fluoride sol solution in the die 1 to 75 ℃, and then cooling to 30 ℃ to obtain the polyvinylidene fluoride porous gel.

Example 11

in the step (1), polyvinylidene fluoride, N-Dimethylformamide (DMF) and formic acid are mixed to make polyvinylidene fluoride: n, N-dimethylformamide: the mass ratio of formic acid is 10: 80: 20, uniformly mixing the solution to obtain a polyvinylidene fluoride sol solution; in the step (2), heating the polyvinylidene fluoride sol solution in the die 1 to 90 ℃, and then cooling to 20 ℃ to obtain the polyvinylidene fluoride porous gel.

Example 12

in step (1), cellulose triacetate polymer, ethyl acetate and Dimethylacetamide (DMAC) are mixed such that the ratio of cellulose triacetate polymer: ethyl acetate: the mass ratio of the dimethylacetamide is 10: 80: 20, uniformly mixing the solution to obtain a sol solution of cellulose triacetate polymer; in the step (2), the cellulose triacetate ester polymer in the mold 1 is heated to 90 ℃ and then cooled to 30 ℃ to obtain the porous gel of the cellulose triacetate ester polymer.

Example 13

in step (1), cellulose triacetate polymer, N-Dimethylformamide (DMF) and chloroform are mixed such that the cellulose triacetate polymer: n, N-dimethylformamide: the mass ratio of the trichloromethane is 10: 80: 20, uniformly mixing the solution to obtain a polyvinylidene fluoride sol solution; in the step (2), the cellulose triacetate polymer sol solution in the mold 1 is heated to 75 ℃, and then cooled to 20 ℃ to obtain the porous gel of the cellulose triacetate polymer.

Example 14

The present embodiment provides an electrochemical sensor 2 comprising a first electrode array 21 and a second electrode array 22 located in the same detection channel, the first electrode array 21 and the second electrode array 22 sharing a first reference electrode 20. Wherein the first reference electrode 20 comprises an electrode substrate layer and a reference electrolyte layer which are stacked and arranged basically, the outer surface of the first reference electrode 20 is coated with the prepared hydrophobic porous membrane, and the hydrophobic porous membrane is the porous membrane layer prepared by any one of the methods of examples 8 to 13.

As shown in fig. 3 and 4, the first electrode array 21 includes two enzyme electrodes, specifically, a glucose oxidase electrode and a lactate oxidase electrode 212, and two counter electrodes provided in one-to-one correspondence with the two enzyme electrodes, and for convenience of description, the counter electrode corresponding to the glucose oxidase electrode 211 is referred to as a first counter electrode 213, and the counter electrode corresponding to the lactate oxidase electrode 212 is referred to as a second counter electrode 214. The glucose oxidase electrode 211 includes an electrode base layer and a glucose oxidase layer stacked on the substrate, and the outer surface of the glucose oxidase electrode 211 is coated with a hydrophobic porous membrane. The lactate oxidase electrode 212 includes an electrode base layer and a lactate oxidase layer stacked on the substrate, and the outer surface of the lactate oxidase electrode 212 is covered with a hydrophobic porous membrane. The two counter electrodes are respectively formed by electrode base layers arranged on the substrate. The glucose oxidase electrode 211, the first counter electrode 213 and the first reference electrode 20 form a glucose detection unit, the first reference electrode 20 provides a stable potential, and glucose in the sample to be detected reacts in a glucose oxidase layer in the glucose oxidase electrode 211 to generate an electric signal for detection, so that the detection of the glucose concentration is realized. The lactate oxidase electrode 212, the first counter electrode 213 and the first reference electrode 20 form a lactate detection unit, the first reference electrode 20 provides a stable potential, and the lactate in the sample to be detected reacts in a lactate oxidase layer in the lactate oxidase electrode 212 to generate an electric signal for detection, so that the detection of the concentration of the lactate is realized. The glucose oxidase electrode 211 and the lactate oxidase electrode 212 were coated with a hydrophobic porous membrane layer prepared by any one of the methods of examples 8-13.

The second electrode array 22 comprises 4 ion measurement electrodes, specifically a sodium ion electrode 221, a calcium ion electrode 223, a potassium ion electrode 222 and a chloride ion electrode 224. The sodium ion electrode 221 includes an electrode base layer and a solid electrolyte layer stacked on a substrate, and the outer surface of the sodium ion electrode 221 is coated with a sodium ion selective membrane. The calcium ion electrode 223 includes an electrode base layer and a solid electrolyte layer which are stacked on the substrate, and the outer surface of the calcium ion electrode 223 is coated with a calcium ion selective membrane. The potassium ion electrode 222 includes an electrode base layer and a solid electrolyte layer stacked on a substrate, and the outer surface of the potassium ion electrode 222 is coated with a potassium ion selective membrane. The chloride ion electrode 224 includes an electrode base layer and a solid electrolyte layer stacked on a substrate, and the outer surface of the chloride ion electrode 224 is coated with a chloride ion selective membrane. The sodium ion electrode 221 and the first reference electrode 20 form a sodium ion detection unit, the first reference electrode 20 provides a stable potential, sodium ions in a sample to be detected enter a solid electrolyte layer of the sodium ion electrode 221 through a sodium ion selective membrane, ion conduction is converted into electron conduction through the solid electrolyte layer, an electric signal for detection is generated, and the detection of the solubility of the sodium ions in the sample to be detected is realized. Similarly, the calcium ion electrode 223 and the first reference electrode 20 form a calcium ion detection unit, the potassium ion electrode 222 and the first reference electrode 20 form a potassium ion detection unit, and the chloride ion electrode 224 and the first reference electrode 20 form a chloride ion detection unit, so that the detection of calcium ions, potassium ions and chloride ions in the sample to be detected is realized. The solid electrolyte layer in the sodium ion electrode 221, the calcium ion electrode 223, the potassium ion electrode 222, and the chloride ion electrode 224 is any one of the porous membrane layers prepared in examples 2 to 7, respectively.

In the electrochemical sensor 2, the outer surfaces of the glucose oxidase electrode 211 and the lactate oxidase electrode 212 are coated with the hydrophobic porous membrane, and when glucose components in a sample (such as blood) to be detected enter the electrodes through the pores, an oxidation-reduction reaction is generated to realize the detection of the glucose and the lactic acid, so that the normal detection of the enzyme electrode is prevented from being influenced by the large amount of sample solution flowing into the enzyme electrode. Meanwhile, the hydrophobic porous membrane is favorable for isolating the reaction environment of the enzyme electrode from the reaction environment of the ion measurement electrode, so that the chemical reaction in the enzyme electrode is prevented from influencing the components of the sample solution, and the calcium ion electrode 223, the sodium ion electrode 221, the potassium ion electrode 222 and the chloride ion electrode 224 are dried for normal detection. Through the arrangement, the enzyme electrode and the ion measuring electrode can be arranged in the same detection channel, and the structure and the preparation difficulty of the electrochemical sensor 2 are effectively simplified. On the other hand, the hydrophobic porous membrane is a porous membrane layer prepared by a gelation reaction in the closed reaction chamber, so that gel cracking and pore collapse are effectively prevented, the hydrophobic porous membrane has the advantages of high porosity, high specific surface area, uniform pore diameter and the like, the transport capacity of the hydrophobic porous membrane to a target substance is increased, the structural uniformity is good, and the detection performance of the enzyme electrode is favorably improved. The outer surface of the first reference electrode 20 is coated with a hydrophobic porous membrane, so that the interference of environmental factors is reduced, and the potential stability of the reference electrode is improved. The solid electrolyte layer of the ion measuring electrode is prepared by the preparation method of the porous membrane layer, has the advantages of high potential stability and high capacitance performance, and is beneficial to improving the detection performance of the ion measuring electrode.

The first electrode array 21 and the second electrode array 22 in the same detection channel can share the first reference electrode 20, so that the simultaneous detection of multiple parameters of glucose, lactic acid, potassium ions, calcium ions, sodium ions and chloride ions is realized, and the multi-parameter integrated electrochemical sensor 2 is simple in structure and easy to manufacture.

Example 15

The present embodiment provides an electrochemical sensor 2, which is different from the electrochemical sensor 2 provided in embodiment 14 in that: the electrochemical sensor 2 further comprises a third electrode array 23 and a fourth electrode array 24 located in the same detection channel, the third electrode array 23 and the fourth electrode array 24 sharing the first reference electrode 20.

As shown in fig. 5 and 6, the third electrode array 23 includes pH electrodes 231, O₂Electrode 232, and O₂A third pair of electrodes 235 and CO arranged corresponding to the electrode 232₂ Electrode 233 and CO₂Electrode 233 corresponds to the second reference electrode 234 used. Specifically, the pH electrode 231 includes an electrode base layer and a solid electrolyte layer stacked on the substrate, and the outer surface of the pH electrode 231 is coated with a hydrogen ion selective membrane. O is₂The electrode 232 includes an electrode base layer and O laminated on the substrate₂Electrolyte layer, O₂The outer surface of the electrode 232 is coated with O₂And (3) a breathable film. CO2₂The electrode 233 includes an electrode base layer and a solid electrolyte layer, CO, which are stacked on the substrate₂The outer surface of the electrode is sequentially coated with the hydrogen ion selective membrane and CO from inside to outside₂And (3) a breathable film. The second reference electrode 234 includes an electrode substrate layer and a reference electrolyte layer stacked on the substrate, and the outer surface of the second reference electrode 234 is sequentially coated with a hydrophobic porous membrane and CO from inside to outside₂And (3) a breathable film. Wherein, O₂The gas permeable membrane was the porous membrane layer of any of the preparations of examples 8-13, CO₂The gas permeable membrane was the porous membrane layer of any of examples 8-13, pH electrode 231 and CO₂The solid electrolyte layers of the electrodes 233 were porous membrane layers of any of the examples 2 to 7, respectively. The fourth electrode array 24 includes hematocrit electrodes 241, the hematocrit electrodes 241 being embodied as electrode ground layers on a substrate.

In the electrochemical sensor 2, the hydrophobic porous membrane coated on the outer surface of the enzyme electrode can effectively prevent the redox reaction in the enzyme electrode from being influenced by pH and O₂And CO₂The interference of equal parameters enables the third electrode array 23 and the fourth electrode array 24 to be integrated in the same detection channel, and further realizes the pH and O detection₂And CO₂The blood gas parameter and the hematocrit parameter are synchronously detected, and the electrochemical sensor 2 has wide detection range and high integration level. The third electrode array 23 and the fourth electrode array 24 share the first reference electrode 20, simplifying the structure of the multiparameter integrated electrochemical sensor 2. In addition, due to the pH electrode 231 and CO₂The solid electrolyte layer in the electrode 233 is prepared by the preparation method of the porous membrane layer provided by the invention, has the advantages of high potential stability and high capacitance performance, and is beneficial to improving the detection performance of the electrode. O is₂And CO₂O coated outside electrode 233₂Gas permeable membrane and CO₂The breathable film prepared by the preparation method of the porous film layer provided by the invention has the advantages of high porosity, good uniformity and high permeability to target molecules, and is beneficial to improving the electrode sensitivity.

Example 16

The present embodiment provides a method for manufacturing the electrochemical sensor 2 provided in embodiment 14, specifically including the following steps:

and S1, printing 9 electrode base layers arranged at intervals and conductive leads connected with the electrode base layers on the substrate by adopting a screen printing process. And continuously printing an insulating layer on the substrate, wherein the insulating layer is formed on one side surface of the substrate printing electrode base layer, and the insulating layer avoids the detection area of the printing electrode base layer. The substrate material can be selected from PET, PC, PMMA, PVC, PP, glass, etc.

S2, using any one of the preparation methods provided in examples 2 to 7, 4 electrode substrate layers were arbitrarily selected, and a solid electrolyte layer was prepared on the electrode substrate layers.

S3, adopting a screen printing process, optionally selecting 1 electrode substrate layer, and preparing a reference electrolyte layer on the electrode substrate layer; optionally selecting 2 electrode substrate layers, and respectively preparing a glucose oxidase layer and a lactate oxidase layer on the electrode substrate layers; preparing a chloride ion selective membrane, a calcium ion selective membrane, a potassium ion selective membrane and a sodium ion selective membrane on the outer surface of the electrode of the solid electrolyte layer prepared in step S2 by using a screen printing process to form a chloride ion electrode 224, a calcium ion electrode 223, and a potassium ion and sodium ion electrode 221.

S4, preparing hydrophobic porous membranes on the outer surfaces of the electrodes for preparing the reference electrolyte layer, the glucose oxidase layer, and the lactate oxidase layer, respectively, by any of the preparation methods provided in examples 8 to 13, to obtain the first reference electrode 20, the glucose oxidase enzyme electrode, and the lactate oxidase enzyme electrode. The remaining 2 electrode substrates on the substrate serve as the first pair of electrodes 213 and the second pair of electrodes 214, respectively, to obtain the electrochemical sensor 2 that can be used for simultaneously detecting blood biochemical substances and blood ions.

According to the preparation method, the preparation sequence and the preparation process of each electrode functional layer of the electrochemical sensor 2 are optimized, the preparation process of the electrochemical sensor 2 integrated with multiple parameters can be completed only through 4 steps, the same preparation process is selected in each step of preparation, the preparation efficiency of the electrochemical sensor 2 is effectively improved, and the preparation process is simplified.

Example 17

The present embodiment provides a method for manufacturing the electrochemical sensor 2 provided in embodiment 15, specifically including the following steps:

and S1, printing 14 electrode base layers arranged at intervals and conductive leads connected with the electrode base layers on the substrate by adopting a screen printing process. And continuously printing an insulating layer on the substrate, wherein the insulating layer is formed on one side surface of the substrate printing electrode base layer, and the insulating layer avoids the detection area of the printing electrode base layer. The substrate material can be selected from PET, PC, PMMA, PVC, PP, glass, etc.

S2, preparing a solid electrolyte layer on the electrode substrate layer by arbitrarily selecting 6 electrode substrate layers using any one of the preparation methods provided in examples 2 to 7.

S3, adopting a screen printing process, optionally selecting 2 electrode substrate layers, and preparing a reference electrolyte layer on the electrode substrate layers; optionally selecting 2 electrode substrate layers, and respectively preparing a glucose oxidase layer and a lactate oxidase layer on the electrode substrate layers; preparing O on 1 optional electrode substrate layer by screen printing process₂An electrolyte layer; a screen printing process is used to prepare a chloride ion selective membrane, a calcium ion selective membrane, a potassium ion selective membrane, a sodium ion selective membrane and a hydrogen ion selective membrane on the outer surface of the electrode of the solid electrolyte layer prepared in step S2, so as to form 1 chloride ion electrode 224, 1 calcium ion electrode 223, 1 potassium ion electrode, 1 sodium ion electrode 221 and 2 pH electrodes 231.

S4, preparing hydrophobic porous membranes on the outer surfaces of the electrodes for preparing the reference electrolyte layer, the glucose oxidase layer, and the lactate oxidase layer, respectively, by any of the preparation methods provided in examples 8 to 13, to obtain 2 first reference electrodes 20, 1 glucose oxidase enzyme electrode, and 1 lactate oxidase enzyme electrode. Preparation of O Using any of the preparation methods provided in examples 8-13₂Preparation of outer electrode surface of electrolyte layer₂Gas-permeable film of forming O₂And an electrode 232. Using any of the preparation methods provided in examples 8-13, CO was prepared separately on the outer surfaces of any of first reference electrode 20 and any of pH electrodes 231₂Gas permeable membrane to obtain second reference electrode 234 and CO₂And an electrode 233. 4 electrode bases remained on the substrateThe layers are respectively used as a first pair of electrodes 213, a second pair of electrodes 214, a third pair of electrodes 235 and a hematocrit electrode 241, and the electrochemical sensor 2 which can be simultaneously used for detecting various parameters of blood biochemical substances, blood gas, blood ions and hematocrit is obtained.

According to the preparation method, the preparation sequence and the preparation process of each electrode functional layer of the electrochemical sensor 2 are optimized, the preparation process of the electrochemical sensor 2 integrated with 10 parameters can be completed only through 4 steps, the same preparation process is selected in each step of preparation, the preparation efficiency of the electrochemical sensor 2 is effectively improved, and the preparation process is simplified.

Comparative example 1

The comparative example provides a method for preparing a solid electrolyte layer, the method specifically comprising the steps of:

(2) and coating the graphene sol solution on an electrode substrate layer, and drying to obtain the solid electrolyte layer.

Experimental example 1

1. Purpose of the experiment: and detecting the electrochemical performance of the solid electrolyte layer obtained by the preparation method of the porous membrane layer provided by the invention.

2. The experimental method comprises the following steps: solid electrolyte layers were prepared on the electrode substrate layer by the preparation method provided in example 2 and the preparation method provided in comparative example 1, respectively, and then a hydrogen ion selective membrane preparation solution (a hydrogen ion selective membrane preparation solution having a mass fraction of 15 wt% was obtained by dissolving a solute consisting of 0.5 wt% of type ii hydrogen ionophore, 0.5 wt% of potassium tetrakis (4-chlorophenyl) borate, 33 wt% of dioctyl sebacate, and 66 wt% of polyvinyl chloride in tetrahydrofuran solvent) was applied on the two solid electrolyte layers, followed by drying at room temperature for 24 hours, thereby completing the preparation of two pH electrodes. And the pH electrode and the silver/silver chloride reference electrode form a two-electrode system, and the pH solution is tested.

3. The experimental results are as follows:

fig. 7 shows a graph of response time and potential stability of the pH electrode obtained by the method provided in example 2, fig. 8 shows a standard voltage-concentration curve of the pH electrode obtained by the method provided in example 2, and fig. 9 shows a standard voltage-concentration curve of the pH electrode obtained by the method provided in comparative example 1. As can be seen from FIGS. 7 and 8, the pH electrode has the advantages of fast response time (less than 1s), high stability (CV less than 5%), Nernst response slope 59.07Mv/pH, high signal-to-noise ratio and the like; and the Nernst response slope of the pH electrode obtained by the porous membrane layer provided by the invention is obviously higher than that of the pH electrode (54.77Mv/pH) using the solid electrolyte in the comparative example 1, which shows that the preparation method of the porous membrane layer provided by the invention is beneficial to improving the electrical detection performance of the porous membrane layer applied to the sensor electrode.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims

1. An electrochemical sensor, comprising:

a second electrode array having at least one ion measuring electrode;

the first electrode array and the second electrode array share a first reference electrode, the outer side surfaces of the first reference electrode and the enzyme electrode are coated with a hydrophobic porous membrane, and the hydrophobic porous membrane is a porous membrane layer prepared by the following method and comprises the following steps:

(1) preparing a sol solution, wherein the sol solution is a precursor solution of a hydrophobic porous membrane; (2) placing the precursor solution in a closed reaction chamber, and gelatinizing the precursor solution to obtain porous gel; (3) and drying the porous gel to obtain the porous membrane layer.

2. The electrochemical sensor according to claim 1, wherein the hydrophobic porous membrane is prepared in a method, and the step (1) comprises:

mixing a photoinitiator with polydimethylsiloxane in a first solvent such that the photoinitiator: polydimethylsiloxane: the mass ratio of the first solvent is (0.5-2): 10-20): 70-90, so as to obtain a polydimethylsiloxane sol solution, wherein the polydimethylsiloxane sol solution is a precursor solution of the hydrophobic porous membrane; or,

mixing polyvinylidene fluoride, a second solvent and a third solvent to make the polyvinylidene fluoride: a second solvent: the mass ratio of the third solvent is (5-10): (70-80): (5-20), and a polyvinylidene fluoride sol solution is obtained, wherein the polyvinylidene fluoride sol solution is a precursor solution of the hydrophobic porous membrane; or,

mixing a cellulose triacetate polymer, a fourth solvent, and a fifth solvent such that the cellulose triacetate polymer: a fourth solvent: the mass ratio of the fifth solvent is (5-10): (70-80): (5-20), so as to obtain the solution of the cellulose triacetate polymer sol, and the solution of the cellulose triacetate polymer sol is the precursor solution of the hydrophobic porous membrane.

3. The electrochemical sensor according to claim 2, wherein the first solvent is selected from toluene or cyclohexanone, the second solvent is selected from N, N-dimethylformamide or acetic acid, the third solvent is selected from dimethylacetamide or formic acid, the fourth solvent is selected from N, N-dimethylformamide or ethyl acetate, and the fifth solvent is selected from dimethylacetamide or trichloromethane.

4. The electrochemical sensor of claim 2,

5. The electrochemical sensor according to any one of claims 1 to 4, wherein the enzyme electrode comprises an electrode substrate layer and an oxidase layer which are arranged in a stacked manner, and the hydrophobic porous membrane is coated on the outer surface of the enzyme electrode; the ion measuring electrode comprises an electrode substrate layer, a solid electrolyte layer and an ion selective membrane, wherein the electrode substrate layer and the solid electrolyte layer are arranged in a stacked mode, and the ion selective membrane is coated on the outer surface of the ion measuring electrode; the first reference electrode comprises an electrode substrate layer and a reference electrolyte layer which are arranged in a stacked mode, and the hydrophobic porous membrane is coated on the outer surface of the first reference electrode; the solid electrolyte layer is a porous membrane layer.

6. The electrochemical sensor of any one of claims 1 to 4, further comprising a third electrode array and/or a fourth electrode array sharing the first reference electrode, the third electrode array comprising a pH electrode and the fourth electrode array comprising a hematocrit electrode.

7. The electrochemical sensor of claim 6,

the third electrode array further comprises O₂Electrode with said O₂A counter electrode corresponding to the electrode; and/or the third electrode array further comprises CO₂Electrode, with said CO₂And a second reference electrode corresponding to the electrode.

8. The electrochemical sensor of claim 7,

the pH electrode comprises an electrode substrate layer, a solid electrolyte layer and a hydrogen ion selective membrane, wherein the electrode substrate layer and the solid electrolyte layer are arranged in a stacked mode, and the hydrogen ion selective membrane is coated on the outer surface of the pH electrode; said O is₂The electrode comprises an electrode base layer and an electrode O₂Electrolyte layerAnd coating with said O₂O of the outer surface of the electrode₂A gas permeable membrane; the CO is₂The electrode comprises an electrode basal layer and a solid electrolyte layer which are arranged in a laminated manner, and the electrode is sequentially coated with the CO₂Hydrogen ion selective membrane and CO on the outer surface of the electrode₂A gas permeable membrane; the second reference electrode comprises an electrode substrate layer and a reference electrolyte layer which are arranged in a stacked manner, and a hydrophobic porous membrane and CO which are sequentially coated on the outer surface of the second reference electrode₂And (3) a breathable film.

9. A method of making an electrochemical sensor according to any one of claims 1 to 8, comprising: a first reference electrode, an enzyme electrode, an ion measuring electrode, and a counter electrode are prepared simultaneously on a substrate.

10. The method of claim 9, comprising the steps of:

s2, preparing a solid electrolyte layer on at least 1 electrode substrate layer by using the preparation method of the hydrophobic porous membrane; the hydrophobic porous membrane is a porous membrane layer prepared by the following method, and comprises the following steps:

(1) preparing a sol solution, wherein the sol solution is a precursor solution of a solid electrolyte layer or a hydrophobic porous membrane; (2) placing the precursor solution in a closed reaction chamber, and gelatinizing the precursor solution to obtain porous gel; (3) drying the porous gel to obtain the porous membrane layer;

s4, coating the hydrophobic porous membrane on the outer surface of the electrode for preparing the oxidase layer to form the enzyme electrode; forming said first reference electrode by said hydrophobic porous membrane coated on the outer surface of the electrode from which said reference electrolyte layer is formed; and at least 1 electrode substrate layer is remained on the substrate to form the counter electrode, so that the electrochemical sensor is obtained.

11. The method of claim 10, comprising the steps of:

s2, preparing solid electrolyte layers on the 4 electrode base layers;

s4, coating hydrophobic porous membranes on the outer surfaces of the electrodes for preparing the glucose oxidase layer and the lactate oxidase layer respectively to form a glucose oxidase electrode and a lactate oxidase electrode; coating a hydrophobic porous membrane on the outer surface of the electrode for preparing the reference electrolyte layer to form the first reference electrode; and at least 2 electrode substrate layers are remained on the substrate to form a counter electrode corresponding to the glucose oxidase electrode and the lactate oxidase electrode, so that the electrochemical sensor is obtained.

12. The method for preparing according to claim 10 or 11, characterized by comprising the steps of:

s1, preparing 14 electrode base layers arranged at intervals on the substrate;

s3, preparing a glucose oxidase layer and a lactate oxidase layer on the 2 electrode substrate layers respectively; preparing a reference electrolyte layer on 2 of said electrode substrate layers; preparing 0 on 1 of the electrode base layers₂An electrolyte layer onPreparing a solid electrolyte layer, wherein the outer surface of the electrode of the solid electrolyte layer is respectively coated with a chloride ion selective membrane, a calcium ion selective membrane, a potassium ion selective membrane, a sodium ion selective membrane and a hydrogen ion selective membrane to form 1 chloride ion electrode, 1 calcium ion electrode, 1 potassium ion electrode, 1 sodium ion electrode and 2 pH electrodes;

s4, coating hydrophobic porous membranes on the outer surfaces of the electrodes for preparing the glucose oxidase layer and the lactate oxidase layer respectively to form a glucose oxidase electrode and a lactate oxidase electrode; in the preparation of said 0₂Coating the outer surface of the electrode of the electrolyte layer with 0₂A gas permeable film of form 0₂An electrode; coating a hydrophobic porous membrane on the outer surface of the electrode for preparing the reference electrolyte layer to form 2 first reference electrodes; coating CO on the outer surface of any one of the first reference electrodes₂A gas permeable membrane forming a second reference electrode; coating the CO on the outer surface of any pH electrode₂Gas permeable membrane to form CO₂An electrode; the rest 4 electrode basal layers on the substrate respectively correspond to the counter electrode of the glucose oxidase electrode, the counter electrode of the lactate oxidase electrode and the electrode 0₂A counter electrode of the electrode and a hematocrit electrode to obtain the electrochemical sensor.