A paper-based cellulose interdigitated electrode biosensor and its preparation method

Abstract

A paper-based cellulose interdigitated electrode biosensor and a preparation method thereof, comprising the following steps: S1, preparing poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid); S2, coating the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid prepared in S1 on filter paper in the form of an interdigitated electrode structure, and drying at room temperature to obtain poly( 4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material; S3, adding glucose oxidase solution dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material and drying at room temperature. The biosensor prepared by the present invention has high reaction rate and good stability, and at the same time, improves compatibility with biomaterials.

Description

Technical Field

[0001] The present invention relates to the technical field of paper-based cellulose biosensors, in particular to an interdigital electrode biosensor based on paper-based cellulose and a preparation method thereof. Background Art

[0002] A biosensor is a device that uses biologically active units as sensitive elements, combined with chemical and physical conversion elements, and is highly selective for the analyte. It has the advantages of high sensitivity, fast detection speed, simple operation, and continuous dynamic monitoring. It has broad application prospects in the field of health examination and monitoring.

[0003] Prior art biosensors typically use metal or semiconductor materials as sensor carriers, which results in high manufacturing and processing costs and is also environmentally unfriendly. Consequently, paper-based materials are now commonly used as carriers, including electrochemical and optical sensors. Electrochemical sensors use electrodes printed or coated with conductive materials on paper to detect the electrochemical signals generated by the target substance. Optical sensors utilize changes in optical properties to detect targets through a paper-based platform. However, both types of sensors suffer from limited electrode material choices, uneven conductivity, and poor reusability. Summary of the Invention

[0004] The present invention provides a paper-based cellulose-based interdigital electrode biosensor and a preparation method thereof. The prepared biosensor has a high reaction rate and good stability, which not only improves the compatibility with biological materials but also improves the reusability of the biosensor.

[0005] In order to achieve the above object, the specific scheme adopted by the present invention is: a method for preparing an interdigital electrode biosensor based on paper-based cellulose, comprising the following steps:

[0006] S1, Preparation of poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid:

[0007] Poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid) was prepared using EDOT-S (thienylethylene glycol thiophene), ferrous chloride and sodium persulfate as raw materials. The specific steps are as follows:

[0008] S101, adding ferrous chloride to the EDOT-S aqueous solution and allowing to stand for 20-40 minutes to obtain solution A;

[0009] S102, adding sodium persulfate aqueous solution dropwise to solution A and stirring until the solution becomes viscous. After standing for 2-4 hours, adding acetone and centrifuging to obtain a polymer precipitate;

[0010] S103, dissolving the polymer precipitate obtained in S102 in water, and adding resin to obtain poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid);

[0011] S2, coating the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid prepared in S1 on filter paper in the form of an interdigitated electrode structure and drying at room temperature to obtain a poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material;

[0012] S3, adding the glucose oxidase solution dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid) / filter paper composite material and drying at room temperature.

[0013] As an optimization solution of the above-mentioned method for preparing the interdigital electrode biosensor based on paper-based cellulose: in S101, the concentration of the EDOT-S aqueous solution is 0.05-0.07 g / mL.

[0014] As another optimization solution of the above-mentioned method for preparing the paper-based cellulose interdigitated electrode biosensor: in the above 102, the concentration of the sodium persulfate aqueous solution is 0.14-0.15 g / mL.

[0015] As another optimization scheme for the above-mentioned method for preparing a paper-based cellulose interdigitated electrode biosensor: in S2, a nanocellulose dispersion is first added to poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid, and then the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid added with the nanocellulose dispersion is coated on filter paper.

[0016] As another optimization scheme for the above-mentioned method for preparing an interdigitated electrode biosensor based on paper-based cellulose: the mass ratio of the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid to the nanocellulose dispersion is 1:14-16.

[0017] As another optimized solution of the above-mentioned method for preparing the interdigital electrode biosensor based on paper-based cellulose: S3 includes:

[0018] S301, adding succinic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide to a solvent to obtain a succinic acid crosslinker solution;

[0019] S302, soaking the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)butane-1-sulfonic acid) / filter paper composite material obtained in S2 in a succinic acid crosslinker solution for 25-35 minutes and then drying at room temperature;

[0020] S303, preparing a glucose oxidase solution, and adding it dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material obtained in S302.

[0021] As another optimization scheme of the above-mentioned method for preparing a paper-based cellulose interdigitated electrode biosensor: in S301, the molar ratio of succinic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide in the succinic acid crosslinker solution is 1:2:2.

[0022] As another optimization solution of the above-mentioned method for preparing the paper-based cellulose interdigitated electrode biosensor: in S301, the solvent is a phosphate buffered saline solution.

[0023] As another optimization scheme of the above-mentioned method for preparing the paper-based cellulose interdigitated electrode biosensor: the concentration of the glucose oxidase solution is 10 mg / mol.

[0024] The biosensor was prepared according to the above method.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The present invention provides a paper-based cellulose interdigitated electrode biosensor and a preparation method thereof, wherein filter paper is used as the paper-based material, and poly (4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid (PEDOT:SH) is used as the electrode material and coated on the filter paper in an interdigitated structure. The interdigitated electrode biosensor has the advantages of fast reaction rate and good stability, and can improve the compatibility of the biosensor with biological materials, while also improving the reusability of the biosensor.

[0027] 2. In the present invention, a nanocellulose dispersion is added to poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid. The addition of the nanocellulose dispersion can provide more surface adhesion points for poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid, thereby enhancing the adhesion between poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid and the filter paper substrate, thereby making poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid more firmly adhere to the filter paper.

[0028] 3. In the present invention, the electrode material is coated on the filter paper in an interdigitated electrode structure with a highly branched shape, which does not affect the flexibility of the filter paper and maintains the good electrical conductivity of the electrode material. At the same time, it improves the reaction rate and sensitivity of the electrode.

[0029] 4. In the present invention, before immobilizing glucose oxidase, the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material is first immersed in a succinic acid crosslinker solution, which can fully activate the carboxyl functional groups on the surface of poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid, resulting in good contact between the electrode material and the electrolyte, rapid electron transport, and higher conductivity. At the same time, it is beneficial to the immobilization of glucose oxidase, making it more firmly bound to the base to form a stable complex. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The invention relates to a preparation process of poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid;

[0031] Figure 2 It is the coating of the interdigitated electrode structure;

[0032] Figure 3 It is the fixation process of glucose oxidase. DETAILED DESCRIPTION

[0033] The technical solution of the present invention is further elaborated in detail below in conjunction with specific embodiments. Parts not described and disclosed in detail in the following embodiments of the present invention should be understood as existing technologies known or should be known to those skilled in the art.

[0034] A method for preparing a paper-based cellulose interdigital electrode biosensor comprises the following steps:

[0035] S1, Preparation of poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) -butane-1-sulfonic acid (PEDOT: SH) :

[0036] Poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid) was prepared using EDOT-S, ferrous chloride and sodium persulfate as raw materials. The specific steps are as follows:

[0037] S101, adding ferrous chloride to an EDOT-S aqueous solution, wherein the concentration of the EDOT-S aqueous solution is 0.05-0.07 g / mL, and the mass ratio of EDOT-S to ferrous chloride in the EDOT-S aqueous solution is 1:0.3; after the ferrous chloride is added to the EDOT-S aqueous solution, stirring is carried out uniformly with a stirring rod to ensure that the two are fully reacted, and the solution is allowed to stand for 20-40 minutes to obtain a solution A;

[0038] S102, adding sodium persulfate aqueous solution dropwise to solution A, wherein the concentration of the sodium persulfate aqueous solution is 0.14-0.15 g / mL, and the mass ratio of solution A to the sodium persulfate solution is 3:2. Stirring is continued during the addition of the sodium persulfate aqueous solution until the solution becomes viscous. After standing for 2-4 hours, a polymer solution is obtained. 30-50 mL of acetone solution is added to the polymer solution and stirred evenly. The evenly mixed solution is centrifuged to fully precipitate the polymer in acetone to obtain a polymer precipitate.

[0039] S103, dissolving the polymer precipitate obtained in S102 in water, and adding the resin AMBERLITE HPR1100 sodium form, and continuously stirring to allow the resin AMBERLITE HPR1100 sodium form to fully contact the polymer to obtain poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid);

[0040] S2, the poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) -butane-1-sulfonic acid prepared in S1 is coated on the filter paper in the form of an interdigitated electrode structure. Specifically, the nanocellulose dispersion is first added to the poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) -butane-1-sulfonic acid, and then the poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) -butane-1-sulfonic acid added with the nanocellulose dispersion is coated on the filter paper and dried at room temperature to obtain the poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) -butane-1-sulfonic acid / filter paper composite material.

[0041] In this embodiment, No. 4 filter paper is used, which can more effectively adsorb poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) -butane-1-sulfonic acid.

[0042] The mass ratio of the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid to the nanocellulose dispersion is 1:14-16; the nanocellulose dispersion is added to the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid, and the addition of the nanocellulose dispersion can provide more surface active agents for the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid. The surface adhesion points are enhanced, the adhesion between poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) -butane-1-sulfonic acid and the filter paper substrate is enhanced, and the poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) -butane-1-sulfonic acid adheres more firmly to the filter paper. At the same time, the conductive performance of poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) -butane-1-sulfonic acid is better and more stable, and the surface is more uniform and smooth.

[0043] The electrode material is coated on the filter paper in an interdigitated electrode structure. Specifically, the interdigitated electrode structure consists of multiple parallel interdigitated electrodes with a finger width of 1 mm and a distance of 0.5 mm between the fingers, giving the electrode material a highly branched shape on the filter paper. The interdigitated electrode structure can be bent at angles of 30°, 45°, 60°, and 75°. The resistance of the electrode material increases only slightly with increasing bending angle, and no short circuits are observed. This demonstrates that the interdigitated electrode structure does not affect the flexibility of the filter paper, maintains the electrode material's good electrical conductivity, and improves the electrode's reaction rate and sensitivity.

[0044] Refrigeration and room temperature can promote the crystallization of poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) -butane-1-sulfonic acid, improve its order and charge transport properties, and enhance the conductivity of poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) -butane-1-sulfonic acid. Lower temperatures will lead to insufficient crystallinity, and higher temperatures will lead to thermal decomposition or destruction of the lattice structure. Therefore, in this embodiment, poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) -butane-1-sulfonic acid is coated on filter paper and then dried at room temperature.

[0045] S3, adding the glucose oxidase solution dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid) / filter paper composite material and drying at room temperature. Specifically:

[0046] S301, adding succinic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide to a solvent, wherein the solvent is a phosphate buffered saline solution, to obtain a succinic acid crosslinker solution; the molar ratio of succinic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide in the succinic acid crosslinker solution is 1:2:2.

[0047] S302, the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material obtained in S2 is immersed in a succinic acid crosslinker solution for 25-35 minutes and then dried at room temperature; before immobilizing glucose oxidase, the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material is first immersed in a succinic acid crosslinker solution, which can fully activate the carboxyl functional groups on the surface of poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid, resulting in good contact between the electrode material and the electrolyte, rapid electron transfer and higher conductivity; at the same time, it is beneficial to the immobilization of glucose oxidase, making it more firmly bound to the base to form a stable complex.

[0048] S303, prepare a glucose oxidase solution with a concentration of 10 mg / mol, and add it dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material obtained in S302.

[0049] The measurement principle of the biobed dryness prepared based on the above preparation method is: when glucose is present, glucose oxidase catalyzes the reaction of glucose with oxygen to produce hydrogen peroxide, and the concentration of glucose is determined by measuring the current or potential change of hydrogen peroxide. That is, the glucose content in human sweat can be obtained by non-invasive detection, which shows the broad application prospects of this biosensor in the field of future health examination and monitoring.

[0050] Example 1

[0051] A method for preparing a paper-based cellulose interdigital electrode biosensor comprises the following steps:

[0052] S1, Preparation of poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid:

[0053] Poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid) was prepared using EDOT-S, ferrous chloride and sodium persulfate as raw materials. The specific steps are as follows:

[0054] In step S101, 0.2 g of EDOT-S was weighed and mixed with 4 mL of water. The mixture was stirred continuously to completely dissolve the mixture to obtain an EDOT-S aqueous solution. 0.06 g of ferrous chloride was added to the prepared EDOT-S aqueous solution. The mixture was stirred continuously to ensure a full reaction. The mixture was allowed to stand for 20 min.

[0055] S102, weighing 0.28 g of sodium persulfate and mixing it with 2 mL of water to obtain a sodium persulfate aqueous solution; adding the filtered sodium persulfate aqueous solution dropwise to solution A with continuous stirring during the addition, stirring until the solution becomes viscous, and then allowing it to stand for 3 hours. 40 mL of acetone solution was added to the solution after standing, and the mixture was thoroughly stirred. Then, the mixture was centrifuged at 3500 rpm for 5 minutes to obtain a polymer precipitate;

[0056] S103, the obtained polymer precipitate was mixed with 7 mL of water and allowed to stand for 5 minutes, and then 0.3 g of resin AMBERLITE HPR1100 sodium form was added and stirred. After stirring, the mixture was allowed to stand for 10 minutes to obtain poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid);

[0057] S2, adding the nanocellulose dispersion to poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid, wherein the mass ratio of poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid to the nanocellulose dispersion is 1:14;

[0058] S3, adding the glucose oxidase solution dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid) / filter paper composite material and drying at room temperature. Specifically:

[0059] S301, adding succinic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide to a solvent, wherein the solvent is a phosphate buffered saline solution, to obtain a succinic acid crosslinker solution; the molar ratio of succinic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide in the succinic acid crosslinker solution is 1:2:2.

[0060] S302, the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)butane-1-sulfonic acid) / filter paper composite material obtained in S2 is immersed in a succinic acid crosslinker solution for 25 minutes and then dried at room temperature;

[0061] S303, prepare a glucose oxidase solution with a concentration of 10 mg / mol, and add it dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material obtained in S302.

[0062] Example 2

[0063] A method for preparing a paper-based cellulose interdigital electrode biosensor comprises the following steps:

[0064] S1, Preparation of poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid:

[0065] Poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid) was prepared using EDOT-S, ferrous chloride and sodium persulfate as raw materials. The specific steps are as follows:

[0066] In step S101, 0.28 g of EDOT-S was weighed and mixed with 4 mL of water. The mixture was stirred continuously to completely dissolve the mixture to obtain an EDOT-S aqueous solution. 0.042 g of ferrous chloride was added to the prepared EDOT-S aqueous solution. The mixture was stirred continuously to ensure a full reaction. The mixture was allowed to stand for 20 min.

[0067] S102, weighing 0.3 g of sodium persulfate and mixing it with 2 mL of water to obtain a sodium persulfate aqueous solution; adding the filtered sodium persulfate aqueous solution dropwise to solution A with continuous stirring during the addition, stirring until the solution becomes viscous, and then allowing it to stand for 3 hours. 30 mL of acetone solution was added to the solution after standing, and the mixture was thoroughly stirred. Then, the mixture was centrifuged at 3500 rpm for 5 minutes to obtain a polymer precipitate;

[0068] S103, the obtained polymer precipitate was mixed with 7 mL of water and allowed to stand for 5 minutes, and then 0.3 g of resin AMBERLITE HPR1100 sodium form was added and stirred. After stirring, the mixture was allowed to stand for 10 minutes to obtain poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid);

[0069] S2, adding the nanocellulose dispersion to poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid, wherein the mass ratio of poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid to the nanocellulose dispersion is 1:16;

[0070] S3, adding the glucose oxidase solution dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid) / filter paper composite material and drying at room temperature. Specifically:

[0071] S301, adding succinic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide to a solvent, wherein the solvent is a phosphate buffered saline solution, to obtain a succinic acid crosslinker solution; the molar ratio of succinic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide in the succinic acid crosslinker solution is 1:2:2.

[0072] S302, the poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) butane-1-sulfonic acid / filter paper composite material obtained in S2 is immersed in a succinic acid crosslinker solution for 35 minutes and then dried at room temperature;

[0073] S303, prepare a glucose oxidase solution with a concentration of 10 mg / mol, and add it dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material obtained in S302.

[0074] Example 3

[0075] A method for preparing a paper-based cellulose interdigital electrode biosensor comprises the following steps:

[0076] S1, Preparation of poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid:

[0077] Poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid) was prepared using EDOT-S, ferrous chloride and sodium persulfate as raw materials. The specific steps are as follows:

[0078] In step S101, 0.24 g of EDOT-S was weighed and mixed with 4 mL of water. The mixture was stirred continuously to completely dissolve the mixture to obtain an EDOT-S aqueous solution. 0.072 g of ferrous chloride was added to the prepared EDOT-S aqueous solution. The mixture was stirred continuously to ensure a full reaction. The mixture was allowed to stand for 20 min.

[0079] S102, weighing 0.29 g of sodium persulfate and mixing it with 2 mL of water to obtain a sodium persulfate aqueous solution; adding the filtered sodium persulfate aqueous solution dropwise to solution A with continuous stirring during the addition, stirring until the solution becomes viscous, and then letting it stand for 3 hours. 30 mL of acetone solution was added to the solution after standing, and the mixture was thoroughly stirred. Then, the mixture was centrifuged at 3500 rpm for 5 minutes to obtain a polymer precipitate;

[0080] S103, the obtained polymer precipitate was mixed with 7 mL of water and allowed to stand for 5 minutes, and then 0.3 g of resin AMBERLITE HPR1100 sodium form was added and stirred. After stirring, the mixture was allowed to stand for 10 minutes to obtain poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid);

[0081] S2, adding the nanocellulose dispersion to poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid, wherein the mass ratio of poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid to the nanocellulose dispersion is 1:15;

[0082] S3, adding the glucose oxidase solution dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid) / filter paper composite material and drying at room temperature. Specifically:

[0083] S301, adding succinic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide to a solvent, wherein the solvent is a phosphate buffered saline solution, to obtain a succinic acid crosslinker solution; the molar ratio of succinic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide in the succinic acid crosslinker solution is 1:2:2.

[0084] S302, the poly (4- (2,3-dihydrothieno [3,4-b] [1,4] dioxin-2-ylmethoxy) butane-1-sulfonic acid / filter paper composite material obtained in S2 is immersed in a succinic acid crosslinker solution for 30 minutes and then dried at room temperature;

[0085] S303, prepare a glucose oxidase solution with a concentration of 10 mg / mol, and add it dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material obtained in S302.

[0086] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a paper-based cellulose interdigitated electrode biosensor, characterized in that: The following steps are involved: S1, Preparation of poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid: Poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid) was prepared using EDOT-S, ferrous chloride and sodium persulfate as raw materials. The specific steps are as follows: S101, adding ferrous chloride to the EDOT-S aqueous solution and allowing to stand for 20-40 minutes to obtain solution A; S102, adding sodium persulfate aqueous solution dropwise to solution A and stirring until the solution becomes viscous. After standing for 2-4 hours, adding acetone and centrifuging to obtain a polymer precipitate; S103, dissolving the polymer precipitate obtained in S102 in water, and adding resin to obtain poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid); S2, coating the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid prepared in S1 on filter paper in the form of an interdigitated electrode structure and drying at room temperature to obtain a poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material; S3, adding the glucose oxidase solution dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid) / filter paper composite material and drying at room temperature; S301, adding succinic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide to a solvent to obtain a succinic acid crosslinker solution; S302, soaking the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)butane-1-sulfonic acid) / filter paper composite material obtained in S2 in a succinic acid crosslinker solution for 25-35 minutes and then drying at room temperature; S303, preparing a glucose oxidase solution, and adding it dropwise onto the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid / filter paper composite material obtained in S302.

2. The method for preparing a paper-based cellulose interdigitated electrode biosensor according to claim 1, wherein: In the above-mentioned S101, the concentration of the EDOT-S aqueous solution is 0.05-0.07 g / mL.

3. The method for preparing a paper-based cellulose interdigitated electrode biosensor according to claim 1, wherein: In the step 102 , the concentration of the sodium persulfate aqueous solution is 0.14-0.15 g / mL.

4. The method for preparing a paper-based cellulose interdigitated electrode biosensor according to claim 1, wherein: In the above S2, a nanocellulose dispersion is first added to poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid, and then the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid to which the nanocellulose dispersion is added is coated on filter paper.

5. The method for preparing a paper-based cellulose interdigitated electrode biosensor according to claim 4, wherein: The mass ratio of the poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid to the nanocellulose dispersion is 1:14-16.

6. The method for preparing a paper-based cellulose interdigitated electrode biosensor according to claim 1, wherein: In the S301, the molar ratio of succinic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide in the succinic acid cross-linking agent solution is 1:2:

2.

7. The method for preparing a paper-based cellulose interdigitated electrode biosensor according to claim 1, wherein: In the above-mentioned S301, the solvent is a phosphate buffered saline solution.

8. The method for preparing a paper-based cellulose interdigitated electrode biosensor according to claim 1, wherein: The concentration of the glucose oxidase solution is 10 mg / mol.

9. A biosensor prepared according to the method of any one of claims 1 to 8.

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