High-sensitivity blood glucose test paper and preparation method thereof

Abstract

The invention discloses high-sensitivity blood glucose test paper and a preparation method thereof.The high-sensitivity blood glucose test paper comprises a substrate and an electrode arranged on the substrate, and the electrode is prepared from, by mass, 10-15 parts of graphene, 1-3 parts of a conductive material, 2-15 parts of waterborne epoxy resin, 0.1-5.0 parts of a dispersing agent and 0.5-4.0 parts of a curing agent; and 43-60 parts of a solvent. According to the technical scheme, the wettability of the surface of the electrode is improved.

Description

Technical Field

[0001] This invention relates to the field of blood glucose test strip technology, and in particular to a highly sensitive blood glucose test strip and its preparation method. Background Technology

[0002] Fluctuations in blood sugar levels reflect different states of the body. As people's quality of life continues to improve and lifestyles change, the number of people needing blood sugar management is constantly increasing. Therefore, for people with high blood sugar, regularly monitoring and controlling blood sugar levels is a key method for maintaining health and preventing health problems.

[0003] Among related technologies, using a blood glucose meter for blood glucose testing is a convenient and practical method. People don't need to go to the hospital; they only need to buy a blood glucose meter and test strips to monitor their blood glucose levels at home. However, in practical applications, the electrodes of blood glucose test strips have low wetting properties to the enzyme solution, resulting in low sensitivity in blood glucose measurement. Summary of the Invention

[0004] The main objective of this invention is to provide a highly sensitive blood glucose test strip and its preparation method, which aims to improve the wettability of the electrode surface.

[0005] To achieve the above objectives, the present invention proposes a highly sensitive blood glucose test strip, comprising a substrate and an electrode disposed on the substrate. By mass, the electrode is prepared from the following components: 10-15 parts graphene, 1-3 parts conductive material, 2-15 parts aqueous epoxy resin, 0.1-5.0 parts dispersant, 0.5-4.0 parts curing agent, and 43-60 parts solvent, wherein the curing agent comprises modified fatty amine.

[0006] In one embodiment, the modified fatty amine includes a polyether amine curing agent.

[0007] In one embodiment, the waterborne epoxy resin includes a hydrophilic waterborne epoxy resin.

[0008] In one embodiment, the waterborne epoxy resin has a solid content of 50-80 wt%.

[0009] In one embodiment, at 25°C, the viscosity of the waterborne epoxy resin is in the range of 3000-13000 cps; and / or, the epoxy equivalent (EEQ) of the waterborne epoxy resin is from 190 g / mol to 300 g / mol.

[0010] In one embodiment, the curing agent includes one or more of aliphatic polyamines, aromatic polyamines, modified polyamines, polyamides, or cyclic aliphatic amines.

[0011] In one embodiment, the graphene comprises graphene nanosheets.

[0012] In one embodiment, the graphene has a particle size of 5-10 μm; and / or, the graphene has a pore size of 2-7 nm; and / or, the graphene nanosheets consist of 2-3 layers.

[0013] In one embodiment, the conductive material comprises carbon black or metal powder; and / or, the dispersant comprises dispersant WE-D2117R; and / or, the solvent comprises one or more of N,N-dimethylformamide, N,N-dimethylacetamide, polyvinyl alcohol, polyacrylic acid, polyurethane, acetone, and dichloromethane.

[0014] This invention also proposes a method for preparing a high-sensitivity blood glucose test strip, which includes the following steps:

[0015] Graphene, conductive materials, dispersants, and solvents are mixed and ground to obtain a mixed slurry;

[0016] Under stirring conditions of 900-1200 r / min, waterborne epoxy resin is added to the mixed slurry and stirred at 1500-2000 r / min for more than 1 hour, and then ground until the particle size is below 8 μm.

[0017] Add curing agent and stir evenly to remove bubbles, thus obtaining conductive carbon paste;

[0018] Conductive carbon paste is coated onto a substrate and cured to obtain an electrode.

[0019] In one embodiment, the curing step is performed at room temperature for 10-15 minutes; and / or, in the step of mixing and grinding the graphene, conductive material, dispersant and solvent, the grinding speed is 2500-3000 r / min and the time is 40-70 minutes.

[0020] The technical solution of this invention involves reacting a curing agent with water-based epoxy resin to increase the wettability of the cured electrode surface. This facilitates the adsorption and distribution of glucose oxidase or glucose dehydrogenase solution on the electrode surface, allowing the dried enzyme film to adhere firmly to the electrode. This significantly improves the sensitivity and reliability of the blood glucose test strip. Furthermore, the electrode prepared using the material described in this application exhibits excellent conductivity and stability, further enhancing the sensitivity and accuracy of the blood glucose test strip.

[0021] Furthermore, this application makes a breakthrough by using water-based epoxy resin in the field of blood glucose test strips. This not only improves the wettability of the electrode surface but also stabilizes the dispersibility of conductive particles without affecting the conductivity of the electrode material. In other words, it improves the sensitivity of blood glucose test strips while ensuring the accuracy of detection. This overcomes the limitations of existing technologies that can only use oil-based resins that easily disperse graphene to prepare blood glucose test strips, and represents a breakthrough in the field of blood glucose test strip preparation. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0023] Figure 1 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Embodiment 1 of the present invention.

[0024] Figure 2 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Embodiment 2 of the present invention.

[0025] Figure 3 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Embodiment 3 of the present invention.

[0026] Figure 4 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Embodiment 4 of the present invention.

[0027] Figure 5 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Embodiment 5 of the present invention.

[0028] Figure 6 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Embodiment 6 of the present invention.

[0029] Figure 7 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Embodiment 7 of the present invention.

[0030] Figure 8 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Embodiment 8 of the present invention.

[0031] Figure 9 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Embodiment 9 of the present invention.

[0032] Figure 10 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Embodiment 10 of the present invention.

[0033] Figure 11 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Comparative Example 1 of the present invention.

[0034] Figure 12 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Comparative Example 2 of the present invention.

[0035] Figure 13 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Comparative Example 3 of the present invention.

[0036] Figure 14 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Comparative Example 4 of this invention.

[0037] Figure 15 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip in Comparative Example 5 of this invention.

[0038] Figure 16 This is a graph showing the relationship between blood glucose concentration and response current for the blood glucose test strip of Comparative Example 6 of the present invention.

[0039] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0041] It should be noted that the meaning of "and / or" throughout the text includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution that satisfies both A and B. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0042] The terms “comprising,” “including,” “containing,” “containing,” “having,” or other variations thereof are intended to cover non-closed inclusion, and no distinction is made between these terms. The term “comprising” means that other steps and components may be added without affecting the final result. The term “comprising” also includes the terms “consistently composed of” and “substantially composed of”. The compositions and methods / processes of the present invention comprise, consist of, and substantially consist of the essential elements and limitations described herein, as well as any additional or optional components, parts, steps, or limitations described herein. All numerical values ​​or expressions relating to component amounts, process conditions, etc., used in the specification and claims are to be understood in all cases to be modified by “about.” All ranges relating to the same component or property include endpoints that can be combined independently. Because these ranges are continuous, they include every value between a minimum and a maximum value. It should also be understood that any numerical range referenced in this application is intended to include all subranges within that range. As used herein, “parts by weight,” “number of parts by weight,” “mass parts,” or “mass parts” are used interchangeably. A part by weight can be any fixed weight expressed in milligrams, grams, or kilograms (e.g., 1 mg, 1 g, 2 g, 5 g, or 1 kg). For example, a composition consisting of 1 part by weight of component a and 9 parts by weight of component b can be a composition consisting of 1 gram of component a + 9 grams of component b, or 10 grams of component a + 90 grams of component b, etc.

[0043] This invention proposes a highly sensitive blood glucose test strip.

[0044] In this embodiment of the invention, the high-sensitivity blood glucose test strip includes a substrate and an electrode disposed on the substrate. By mass, the electrode is made of the following components: 10-15 parts graphene, 1-3 parts conductive material, 2-15 parts waterborne epoxy resin, 0.1-5.0 parts dispersant, 0.5-4.0 parts curing agent, and 43-60 parts solvent; wherein the curing agent includes modified fatty amine.

[0045] Further, in one embodiment, the electrode preparation material comprises the following components by mass parts: 12-15 parts graphene, 1-3 parts conductive material, 5-12 parts waterborne epoxy resin, 0.1-3.0 parts dispersant, 1.2-3.0 parts curing agent, and 50-55 parts solvent.

[0046] The technical solution of this invention involves reacting a curing agent with water-based epoxy resin to improve the wettability of the cured electrode surface. This facilitates the adsorption and distribution of glucose oxidase or glucose dehydrogenase solutions on the electrode surface, allowing the dried enzyme film to adhere firmly to the electrode, thereby improving the sensitivity and reliability of the blood glucose test strip. Furthermore, the electrode prepared using the material described in this application exhibits excellent conductivity and stability, further enhancing the sensitivity and accuracy of the blood glucose test strip.

[0047] Furthermore, this application makes a breakthrough by using water-based epoxy resin in the field of blood glucose test strips. This not only improves the wettability of the electrode surface but also stabilizes the dispersibility of conductive particles without affecting the conductivity of the electrode material. In other words, it improves the sensitivity of blood glucose test strips while ensuring the accuracy of detection. This overcomes the limitations of existing technologies that can only use oil-based resins that easily disperse graphene to prepare blood glucose test strips, and represents a breakthrough in the field of blood glucose test strip preparation.

[0048] It is understood that the electrode is made of conductive carbon paste. Using this conductive carbon paste to prepare the electrode allows for the detection of the current signal generated during the reaction of the bio-enzyme (glucose oxidase or glucose dehydrogenase) with glucose in the electrode reaction zone, thus obtaining the corresponding blood glucose concentration value. The conductive carbon paste is cured on the surface of a substrate to form the electrode. The substrate material can be PET, PP, PC, or PVC.

[0049] Specifically, graphene is a single-layer hexagonal honeycomb lattice structure formed by carbon atoms bonded by sp² hybridization. It has extremely high conductivity and can significantly improve the conductivity of conductive carbon paste, so that the electrode has good and stable conductivity, and the transmission of current signals is faster and more reliable, thereby improving the sensitivity of blood glucose test strips.

[0050] The graphene can be a nanomaterial, and in one embodiment, the graphene comprises graphene nanosheets. Graphene nanosheets are composed of single or multiple layers of graphene sheets and possess many unique properties, including excellent electrical conductivity, thermal conductivity, and mechanical properties, thereby further improving the conductivity and structural performance of the electrode.

[0051] Furthermore, in one embodiment, the graphene particle size is 5-10 μm to improve the conductivity of the electrode, thereby enhancing the sensitivity of the blood glucose test strip. In another embodiment, the graphene pore size is 2-7 nm, and the porous nature of graphene provides excellent adsorption for enzyme solutions, while also increasing the contact area with the enzyme solution, resulting in a large reaction area between the sample and the enzyme, thus facilitating contact between the electrode and the sample and the transmission of current signals. In one embodiment, the graphene nanosheets are in 2-3 layers, which on the one hand facilitates graphene dispersion and avoids aggregation and precipitation; on the other hand, it helps to form a denser microstructure and a good conductive network, improving the conductivity of the electrode.

[0052] Specifically, conductive materials are used to improve the conductivity of conductive carbon paste, making the conductivity and stability of the electrode more reliable. Various conductive materials are available; in one embodiment, the conductive material includes carbon black or metal powder. Further, in one embodiment, the carbon black has a particle size of 10-120 nm. The carbon black can be one or more of acetylene black, conductive furnace black, and superconducting carbon black, such as conductive carbon black N990, Super P Li, etc. In another embodiment, the metal powder includes one or more of gold, platinum, palladium, silver, and silver / silver chloride.

[0053] Specifically, waterborne epoxy resin is a stable dispersion system in which epoxy resin is dispersed in the form of microparticles or droplets in a dispersion medium with water as the continuous phase. The conductive carbon paste of this application, by adding waterborne epoxy resin and other components, improves the wettability of the cured electrode surface, which is beneficial for the adhesion of the enzyme solution and also enhances the adhesion between the electrode and the substrate. Furthermore, waterborne epoxy resin does not affect the performance of other components, exhibiting minimal interference; and it is a green material with good environmental performance and low environmental impact.

[0054] In one embodiment, the waterborne epoxy resin includes a hydrophilic waterborne epoxy resin, which makes the cured electrode have good hydrophilicity, the conductive carbon paste has high adhesion to the substrate, and also improves the dispersion stability of the conductive carbon paste.

[0055] In one embodiment, the waterborne epoxy resin has a solid content of 50-80 wt%. Solid content refers to the percentage of solid epoxy resin in the epoxy resin dispersion. To ensure good coating performance and curing speed of the conductive carbon paste, the waterborne epoxy resin has a solid content of 50-80 wt%. In another embodiment, the waterborne epoxy resin has a solid content of 58-62 wt%. This waterborne epoxy resin may be Nan Ya brand NPEW-254W60.

[0056] In one embodiment, the epoxy equivalent (EEQ) of the waterborne epoxy resin is from 190 g / mol to 300 g / mol. Epoxy equivalent refers to the number of epoxy groups contained in each epoxy equivalent. By using an epoxy equivalent of 190 g / mol to 300 g / mol for the waterborne epoxy resin, excessively high or low resin viscosity is avoided, thus facilitating the coating of conductive carbon paste. In another embodiment, the epoxy equivalent (EEQ) of the waterborne epoxy resin is from 190 g / mol to 250 g / mol.

[0057] In one embodiment, the viscosity range of the waterborne epoxy resin at 25°C is 3000-13000 cps. Further, in another embodiment, the viscosity range of the waterborne epoxy resin at 25°C is 3000-8000 cps. This viscosity range of 3000-8000 cps facilitates the coating of conductive carbon paste, forming a uniform electrode, avoiding excessively fast or slow electrode curing speeds, and ensuring the electrode thickness.

[0058] Specifically, the curing agent includes a modified fatty amine. The modified fatty amine promotes the cross-linking and curing of waterborne epoxy resin, forming a network-like three-dimensional polymer with high cross-linking density. Furthermore, the epoxy groups of the waterborne epoxy resin react with the water in the waterborne epoxy resin to form hydroxyl groups, thereby dramatically increasing the hydrophilicity of the network, resulting in a cured electrode with good wettability and adsorption properties. In addition, the modified fatty amine can also increase the curing speed of the electrode, which is beneficial for electrode curing and shaping.

[0059] There are various types of curing agents; in one embodiment, it can be a polyetheramine curing agent. By crosslinking and curing the polyetheramine curing agent with the waterborne epoxy resin, a network-like three-dimensional polymer with high crosslinking density and high hydrophilicity is formed, improving hydrophilicity without reducing the conductivity of the electrode. In one embodiment, the polyetheramine curing agent includes aliphatic amine polyether diamine. In one embodiment, the polyetheramine curing agent used is Jeffamine® ED-600.

[0060] Specifically, dispersants facilitate the dispersion of graphene, conductive materials, and waterborne epoxy resins in solvents. In one embodiment, the dispersant includes dispersant WE-D2117R, which effectively reduces the aggregation, agglomeration, and precipitation of graphene and conductive materials, improving the dispersion effect of graphene and other materials, thereby enhancing the stability of the dispersion of substances in the conductive carbon paste. Further, in one embodiment, dispersant WE-D2117R is Sinno® WE-D2117R. In another embodiment, the dispersant includes dispersant L-64 (Adeka Corporation), which improves the dispersibility of graphene, conductive materials, and waterborne epoxy resins in solvents.

[0061] In one embodiment, the solvent includes one or more of N,N-dimethylformamide, N,N-dimethylacetamide, polyvinyl alcohol, polyacrylic acid, polyurethane, acetone, and dichloromethane.

[0062] This invention also proposes a method for preparing a highly sensitive blood glucose test strip, comprising the following steps:

[0063] S10, graphene, conductive material, dispersant and solvent are mixed and ground to obtain a mixed slurry;

[0064] S20. Under stirring conditions of 900-1200 r / min, add waterborne epoxy resin to the mixed slurry, stir at 1500-2000 r / min for more than 1 hour, and then grind until the particle size is below 10 μm.

[0065] S30. Add curing agent and stir evenly to remove bubbles and obtain conductive carbon paste;

[0066] S40: Conductive carbon paste is coated onto the substrate and cured to obtain the electrode.

[0067] Specifically, in step S10, graphene, conductive material, dispersant, and solvent can be ground in a sand mill using glass or zirconium balls with a diameter of 0.3-0.5 mm. The ratio of the glass or zirconium balls to the grinding materials (graphene, conductive material, dispersant, and solvent) can be 2:10 to ensure uniform dispersion of the graphene and conductive material and prevent aggregation and precipitation. In one embodiment, in the step of mixing and grinding the graphene, conductive material, dispersant, and solvent, the grinding speed is 2500-3000 r / min, and the time is 40-70 minutes.

[0068] In step S20, the mixed slurry is transferred to a mixer and stirred at 900-1200 rpm. Then, waterborne epoxy resin is added, and the mixture is stirred at 1500-2000 rpm for at least 1 hour. After stirring, the slurry is ground using a sand mill with glass or zirconium balls until the particle size is below 8 μm. This grinding process after stirring not only ensures sufficient contact between the waterborne epoxy resin and the graphene and conductive materials, facilitating subsequent reactions, but also reduces aggregation and precipitation.

[0069] In step S30, the curing agent is added to the slurry and stirred until homogeneous. This can be done using a mixer, or it can be added after grinding the slurry to a particle size of less than 8μm in step S20, followed by further grinding for 5-10 minutes to ensure uniform dispersion of the curing agent. Adding the curing agent and then stirring and grinding promotes uniform dispersion, further reducing the aggregation and precipitation of the conductive carbon slurry. Degassing can be performed by allowing the mixture to stand, or by placing the curing agent and slurry into a degassing mixer and performing degassing simultaneously with the mixing.

[0070] In step S40, conductive carbon paste is coated onto the substrate, which can be printed onto the substrate surface. After the conductive carbon paste cures, electrodes are formed on the substrate surface. In one embodiment, the curing step involves curing at room temperature for 10-15 minutes, thus eliminating the need for heating. Through the interaction between the curing agent and the waterborne epoxy resin, and with specific components and amounts such as graphene, conductive materials, dispersants, and solvents, the preparation process does not require heating for curing. Even with waterborne epoxy resins that are difficult to dry, it can be cured at room temperature, greatly improving curing efficiency.

[0071] The embodiments of the present invention will be described in detail below with reference to specific examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer are followed. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0072] Example 1

[0073] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 13 parts graphene, 2 parts carbon black, 10 parts aqueous epoxy resin, 2 parts dispersant WE-D2117R, 2.5 parts fatty amine polyether diamine 650, and 52 parts N,N-dimethylacetamide. The aqueous epoxy resin used is Nanya NPEW-254W60, and the fatty amine polyether diamine used is Jeffamine® ED-600.

[0074] The preparation method of this blood glucose test strip includes the following steps:

[0075] S10, graphene, conductive material, dispersant and solvent are mixed and ground at a speed of 2800 r / min for 60 minutes to obtain a mixed slurry;

[0076] S20. Under stirring conditions of 1000 r / min, add waterborne epoxy resin to the mixed slurry, stir at 1600 r / min for 70 minutes, and then grind until the particle size is below 8 μm.

[0077] S30. Add curing agent and stir evenly to remove bubbles and obtain conductive carbon paste;

[0078] S40 conductive carbon paste is coated onto the substrate and cured at room temperature for 10 minutes to obtain the electrode.

[0079] Example 2

[0080] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 15 parts graphene, 2 parts carbon black, 10 parts aqueous epoxy resin, 2 parts dispersant WE-D2117R, 2.5 parts fatty amine polyether diamine, and 52 parts N,N-dimethylacetamide. The aqueous epoxy resin used is Nanya NPEW-254W60, and the fatty amine polyether diamine used is Jeffamine® ED-600.

[0081] The preparation method of the blood glucose test strip is the same as in Example 1.

[0082] Example 3

[0083] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 12 parts graphene, 2 parts carbon black, 12 parts aqueous epoxy resin, 2 parts dispersant WE-D2117R, 2.5 parts fatty amine polyether diamine, and 52 parts N,N-dimethylacetamide. The aqueous epoxy resin used is Nanya NPEW-254W60, and the fatty amine polyether diamine used is Jeffamine® ED-600.

[0084] The preparation method of the blood glucose test strip is the same as in Example 1.

[0085] Example 4

[0086] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 15 parts graphene, 2 parts carbon black, 15 parts aqueous epoxy resin, 2 parts dispersant WE-D2117R, 3.0 parts fatty amine polyether diamine, and 52 parts N,N-dimethylacetamide. The aqueous epoxy resin used is Nanya NPEW-254W60, and the fatty amine polyether diamine used is Jeffamine® ED-600.

[0087] The preparation method of the blood glucose test strip is the same as in Example 1.

[0088] Example 5

[0089] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 10 parts graphene, 1.5 parts carbon black, 8 parts aqueous epoxy resin, 2 parts dispersant WE-D2117R, 2.0 parts fatty amine polyether diamine, and 50 parts N,N-dimethylacetamide. The aqueous epoxy resin used is Nanya NPEW-254W60, and the fatty amine polyether diamine used is Jeffamine® ED-600.

[0090] The preparation method of the blood glucose test strip is the same as in Example 1.

[0091] Example 6

[0092] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 11 parts graphene, 2 parts carbon black, 5 parts aqueous epoxy resin, 2 parts dispersant WE-D2117R, 2.5 parts fatty amine polyether diamine, and 50 parts N,N-dimethylacetamide. The aqueous epoxy resin used is NPEW-254W60, and the fatty amine polyether diamine used is Jeffamine® ED-600.

[0093] The preparation method of the blood glucose test strip is the same as in Example 1.

[0094] Example 7

[0095] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 14 parts graphene, 2 parts carbon black, 10 parts aqueous epoxy resin, 2 parts dispersant WE-D2117R, 3.0 parts fatty amine polyether diamine, and 52 parts N,N-dimethylacetamide. The aqueous epoxy resin used is Nanya NPEW-254W60, and the fatty amine polyether diamine used is Jeffamine® ED-600.

[0096] The preparation method of the blood glucose test strip is the same as in Example 1.

[0097] Example 8

[0098] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 13 parts graphene, 2 parts carbon black, 10 parts aqueous epoxy resin, 2 parts dispersant WE-D2117R, 2.5 parts fatty amine polyether diamine, and 50 parts N,N-dimethylacetamide. The aqueous epoxy resin used is Nanya NPEW-254W60, and the fatty amine polyether diamine used is Jeffamine® ED-600.

[0099] The preparation method of the blood glucose test strip is the same as in Example 1.

[0100] Example 9

[0101] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is made of the following materials: 14 parts graphene, 2 parts carbon black, 10 parts aqueous epoxy resin, 2 parts dispersant WE-D2117R, 2.5 parts fatty amine polyether diamine, and 50 parts polyacrylic acid. The aqueous epoxy resin used is Nan Ya NPEW-254W60, and the fatty amine polyether diamine used is Jeffamine® ED-600.

[0102] The preparation method of the blood glucose test strip is the same as in Example 1.

[0103] Example 10

[0104] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 13 parts graphene, 2 parts carbon black, 12 parts aqueous epoxy resin, 2 parts dispersant WE-D2117R, 2.5 parts fatty amine polyether diamine, and 52 parts polyacrylic acid. The aqueous epoxy resin used is Nan Ya NPEW-254W60, and the fatty amine polyether diamine used is Jeffamine® ED-600.

[0105] The preparation method of the blood glucose test strip is the same as in Example 1.

[0106] Comparative Example 1

[0107] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 13 parts graphene, 2 parts carbon black, 2 parts dispersant WE-D2117R, 2.5 parts fatty amine polyether diamine, and 52 parts N,N-dimethylacetamide. The fatty amine polyether diamine used is Jeffamine® ED-600.

[0108] The preparation method of the blood glucose test strip is the same as in Example 1, and it is cured at room temperature for 5 hours.

[0109] Comparative Example 2

[0110] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 13 parts graphene, 2 parts carbon black, 30 parts aqueous epoxy resin, 2 parts dispersant WE-D2117R, 10 parts fatty amine polyether diamine, and 52 parts N,N-dimethylacetamide. The aqueous epoxy resin includes Nanya NPEW-254W60, and the fatty amine polyether diamine is Jeffamine® ED-600.

[0111] The preparation method of the blood glucose test strip is the same as that in Example 1, and it is cured at room temperature for 12 hours.

[0112] Comparative Example 3

[0113] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 13 parts graphene, 2 parts carbon black, 1 part aqueous epoxy resin, 2 parts dispersant WE-D2117R, 0.1 parts fatty amine polyether diamine, and 52 parts N,N-dimethylacetamide. The aqueous epoxy resin used is Nanya NPEW-254W60, and the fatty amine polyether diamine used is Jeffamine® ED-600.

[0114] The preparation method of the blood glucose test strip is the same as in Example 1, and it is cured at room temperature for 8 hours.

[0115] Comparative Example 4

[0116] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 13 parts graphene, 2 parts carbon black, 10 parts aqueous epoxy resin, 2 parts dispersant WE-D2117R, 2.5 parts ethylenediamine, and 52 parts N,N-dimethylacetamide. The aqueous epoxy resin used is Nanya NPEW-254W60, and the fatty amine polyether diamine used is Jeffamine® ED-600.

[0117] The preparation method of the blood glucose test strip is the same as in Example 1, and it is cured at room temperature for 18 hours.

[0118] Comparative Example 5

[0119] A highly sensitive blood glucose test strip includes a substrate and an electrode disposed on one side of the substrate. By weight, the electrode is prepared from the following materials: 13 parts graphene, 2 parts carbon black, 10 parts bisphenol A type epoxy resin, 2 parts dispersant WE-D2117R, 2.5 parts maleic anhydride curing agent, and 52 parts N,N-dimethylacetamide. The bisphenol A type epoxy resin used is E51 epoxy resin.

[0120] The blood glucose test strips were prepared using the same method as in Example 1, and were cured at 160°C for 4 hours.

[0121] Please refer to Table 1 for the components and quantities of Examples 1 to 10, Comparative Examples 1 to 3, and Comparative Example 5 above, and they were prepared according to the above-described method for preparing blood glucose test strips.

[0122] Table 1. Components and their quantities for each sample

[0123]

[0124] Furthermore, the applicant purchased a popular blood glucose test strip (electrochemical type) as a comparative example 6.

[0125] To verify the various performance characteristics of the blood glucose test strip electrodes, samples that had been coated with enzyme solution (containing a glucose dehydrogenase aqueous solution with a mass concentration of 1‰) and dried, respectively, as described in the 10 examples and 5 comparative examples, were subjected to performance tests, such as conductivity, wetting properties, and adhesion properties, and compared with Comparative Example 4. The test results are shown in Table 2. Figures 1 to 16 .

[0126] (1) Wetting performance: On the electrode surface without enzyme solution, drop the enzyme solution onto the electrode surface and measure the contact angle of the enzyme solution on the electrode surface using a contact angle measuring instrument (DSA100). Measure 5 times and take the average value.

[0127] (2) Adhesion performance: Rub the electrodes on the substrate for five minutes and observe whether the enzyme film formed by the enzyme solution detaches.

[0128] (3) Sensitivity: The equilibrium current under different blood glucose concentrations was tested using the IT testing technology on an electrochemical workstation, and the response current versus blood glucose concentration curve was obtained.

[0129] (4) Conductivity: The resistivity of the electrode was tested using a four-probe test method. The test time included three months after preparation and one year of storage at room temperature.

[0130] Table 2 Sample performance test results

[0131]

[0132] As shown in Tables 1 and 2, the contact angles of the electrodes in Examples 1 to 10 are all less than 9°, while the contact angles of Comparative Examples 1 to 5 are all greater than 30°, which is significantly larger than the contact angles of Examples 1 to 10 of this application. Comparative Example 6, being a commercially available product, was not tested because an enzyme film had already formed. Therefore, the blood glucose test strip electrode of this application has a small contact angle and good wetting properties, which facilitates the adsorption and distribution of glucose oxidase solution or glucose dehydrogenase solution on the electrode surface, thereby giving the blood glucose test strip of this application higher sensitivity.

[0133] Regarding adhesion performance, after five minutes of rubbing, the enzyme membranes of Examples 1 to 10 remained intact, with no visible detachment. In Comparative Example 1, the conductive carbon paste, which did not contain water-based epoxy resin, showed a detachment area as high as 80%. Comparative Examples 2 and 5 also exhibited large-area detachment, with detachment areas exceeding approximately 23%. Furthermore, the commercially available Comparative Example 6 showed a detachment area of ​​approximately 15%. Therefore, this demonstrates that the blood glucose test strip electrode of this application has good adhesion performance and can firmly adhere to the enzyme membrane.

[0134] Linear fitting curves of different blood glucose concentrations and response currents for the samples are shown in the figure. Figures 1 to 16 The sensitivities of Examples 1 to 10 were 0.8069-0.8682 μA / mmol / L, corresponding to the linear fitting curve R. 2 The minimum value was 0.987, indicating that the electrode prepared in this application has a good linear response to glucose, and the blood glucose test strip has high sensitivity. The sensitivity of Comparative Example 1 was only 0.005 μA / mmol / L, while Comparative Examples 2 and 3, although showing linear fitting curves R... 2 It is greater than 0.9, but its sensitivity is less than 0.16 μA / mmol / L. Comparative Example 4 uses other curing agents, although its linear fitting curve R... 2The linear fitting curve for Comparative Example 6 is 0.8873, but the sensitivity is 0.2394 μA / mmol / L. Comparative Example 5, using other oxidizing resins and curing agents, showed a slightly higher sensitivity than Comparative Example 4. The linear fitting curve for Comparative Example 6 shows R0. 2 The value is 0.9868, and its sensitivity is 0.3558 μA / mmol / L, which is less than half that of the blood glucose test strip in this application.

[0135] Based on adhesion performance, contact angle, and sensitivity, the blood glucose test strip of this application passed the adhesion performance test, exhibiting a small contact angle and high sensitivity, thus improving electrode wettability and sensitivity. In contrast, Comparative Examples 1 to 6 all showed varying degrees of area detachment, relatively large contact angles, and low sensitivity values, indicating that the comparative examples had low electrode wettability and generally low sensitivity.

[0136] According to the four-probe test results, the resistivity of Examples 1 to 10 within three months and one year was 0.007-0.009 Ω·cm, which is less than that of Comparative Example 6 (0.031 Ω·cm and 0.042 Ω·cm), indicating that the conductivity of the electrode in this application is superior to that of commercially available products. In contrast, the resistivity of Comparative Examples 1 to 5 was greater than 0.1 Ω·cm within three months of preparation, and the resistivity of Comparative Example 1 increased by as much as 83.5% after one year compared to the three-month period. However, the resistivity of Examples 1 to 10 only increased by 16.7% or even remained unchanged after one year. Therefore, this demonstrates that the electrode in this application has excellent conductivity and high stability.

[0137] Therefore, the electrodes of the blood glucose test strip of this application have good wettability and adhesion, which is beneficial for the adsorption of enzyme solution and the adhesion of enzyme membrane after drying. They also exhibit high sensitivity, thereby improving the accuracy of blood glucose test strip detection. Furthermore, the electrodes of the blood glucose test strip of this application have low resistivity, high stability, and good conductivity.

[0138] Unless otherwise specified, the raw materials and equipment used in this invention are commonly used in the field; the methods used in this invention are conventional methods in the field. Unless otherwise specified, the meanings of the terms in this specification are the same as those generally understood by those skilled in the art, but in case of conflict, the definitions in this specification shall prevail.

[0139] The foregoing examples are merely illustrative, used to explain some features of the method described in this invention. The appended claims are intended to claim the broadest possible scope, and the embodiments presented herein are merely illustrative of selected implementations based on combinations of all possible embodiments. Therefore, the applicant intends that the appended claims are not limited by the selection of examples illustrating the features of the invention. Some numerical ranges used in the claims also include sub-ranges within them, and variations within these ranges should also be interpreted as being covered by the appended claims where possible.

Claims

1. A highly sensitive blood glucose test strip, characterized in that, The blood glucose test strip includes a substrate and an electrode disposed on the substrate. By mass, the electrode preparation material includes the following components: 10-15 parts graphene, 1-3 parts conductive material, 2-15 parts waterborne epoxy resin, 0.1-5.0 parts dispersant, 0.5-4.0 parts curing agent, and 43-60 parts solvent. The curing agent includes a modified fatty amine.

2. The high-sensitivity blood glucose test strip as described in claim 1, characterized in that, The modified fatty amine includes polyether amine curing agents.

3. The high-sensitivity blood glucose test strip as described in claim 2, characterized in that, The waterborne epoxy resin includes a hydrophilic waterborne epoxy resin.

4. The high-sensitivity blood glucose test strip as described in claim 3, characterized in that, The waterborne epoxy resin has a solid content of 50-80 wt%.

5. The high-sensitivity blood glucose test strip as described in claim 4, characterized in that, At 25°C, the viscosity range of the waterborne epoxy resin is 3000-13000 cps; and / or, The epoxy equivalent (EEQ) of the waterborne epoxy resin is from 190 g / mol to 300 g / mol.

6. The high-sensitivity blood glucose test strip as described in any one of claims 1 to 5, characterized in that, The graphene includes graphene nanosheets.

7. The high-sensitivity blood glucose test strip as described in claim 6, characterized in that, The graphene has a particle size of 5-10 μm; and / or, The graphene has a pore size of 2-7 nm; and / or, The graphene nanosheets consist of 2-3 layers.

8. The high-sensitivity blood glucose test strip as described in claim 7, characterized in that, The conductive material includes carbon black or metal powder; and / or, The dispersant includes dispersant WE-D2117R; and / or, The solvent includes one or more of N,N-dimethylformamide, N,N-dimethylacetamide, polyvinyl alcohol, polyacrylic acid, polyurethane, acetone, and dichloromethane.

9. A method for preparing a high-sensitivity blood glucose test strip as described in any one of claims 1 to 8, characterized in that, Includes the following steps: Graphene, conductive materials, dispersants, and solvents are mixed and ground to obtain a mixed slurry; Under stirring conditions of 900-1200 r / min, waterborne epoxy resin is added to the mixed slurry and stirred at 1500-2000 r / min for more than 1 hour, and then ground until the particle size is below 8 μm. Add curing agent and stir evenly to remove bubbles, thus obtaining conductive carbon paste; Conductive carbon paste is coated onto a substrate and cured to obtain an electrode.

10. The method for preparing a high-sensitivity blood glucose test strip as described in claim 9, characterized in that, In the curing step, curing is performed at room temperature for 10-15 minutes; and / or, In the step of mixing and grinding the graphene, conductive material, dispersant and solvent, the grinding speed is 2500-3000 r / min and the time is 40-70 minutes.

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