Zwitterionic polymer hydrogel and preparation method and application thereof

Abstract

The application discloses a zwitterionic polymer hydrogel and a preparation method and application thereof. In the preparation method, THMA is dissolved in water, stirred and dispersed to form a THMA suspension; AM, SBMA, an initiator and a crosslinking agent are added into the THMA suspension and stirred uniformly to prepare a precursor liquid; and a free radical polymerization reaction of the precursor liquid is carried out to prepare the zwitterionic polymer hydrogel. The method has simple process and reasonable design, and the polymer hydrogel with mechanical performance and conductive performance is obtained, so that the hydrogel has a double-attack promoting effect of promoting wound healing and simultaneously monitoring the wound healing in real time, and has a wide application prospect.

Description

Technical Field

[0001] This invention belongs to the field of intelligent monitoring and sensing technology, and relates to an amphoteric polymer hydrogel, its preparation method and application. Background Technology

[0002] Conductive hydrogels are water-rich materials that mimic the softness of human tissue and provide the necessary moist environment for wound healing. These hydrogels can absorb tissue exudate, allow oxygen penetration, and cool the wound, thereby reducing patient pain. Effective medical dressings must possess good conductivity, adhesion, and biocompatibility to ensure signal accuracy and patient safety. Among various hydrogels, zwitterionic hydrogels have attracted widespread attention due to their conductivity, low cost, and ease of preparation. These hydrogels contain both cationic and anionic groups, which can enhance conductivity by promoting the movement of ions along the polymer backbone. Existing research typically improves the conductivity of sensors by adding conductive materials, but this may affect the mechanical properties and adhesion of the hydrogel. Furthermore, wound healing is a complex and dynamic physiological and biochemical process. However, traditional wound dressings (such as gauze, bandages, and cotton cloth) have significant shortcomings. For example, patents CN202210080243.5 and CN201720686560.6 disclose nonwoven wound dressings and their applications, respectively. While these dressings support wound healing, they cannot effectively maintain a moist environment and elasticity, and lack real-time monitoring capabilities, which limits the diagnosis and treatment by healthcare professionals and thus increases the burden on patients. Summary of the Invention

[0003] To address the problems existing in the prior art, this invention provides an amphoteric polymer hydrogel, its preparation method, and its application, thereby solving the technical problem that existing technologies cannot simultaneously achieve both mechanical and electrical properties.

[0004] This invention is achieved through the following technical solution:

[0005] A method for preparing an amphoteric polymer hydrogel includes the following steps:

[0006] S1: Dissolve THMA in water, stir and disperse to form a THMA suspension;

[0007] S2: Add AM, SBMA, initiator and crosslinking agent to the THMA suspension, stir evenly to obtain the precursor liquid;

[0008] S3: The precursor fluid undergoes a free radical polymerization reaction to obtain the zwitterionic polymer hydrogel.

[0009] Preferably, in step S1, the ratio of THMA to water is (40~90):300, based on mass fraction.

[0010] Preferably, in step S2, the molar ratio of SBMA to THMA is (1~9):(9~1).

[0011] Preferably, in step S2, the molar ratio of SBMA to THMA is 6:4.

[0012] Preferably, in step S2, the ratio of AM, SBMA, initiator and crosslinking agent is 20:(20~100):6:1, based on mass fraction.

[0013] Preferably, in step S2, the initiator is at least one selected from ammonium persulfate, potassium persulfate, azobisisobutylamidine hydrochloride, azobisisobutylimidazoline hydrochloride, azobiscyanopentanoic acid, and azobisisopropylimidazoline.

[0014] Preferably, in step S2, the crosslinking agent is at least one selected from polyethylene glycol diglycidyl ether, N,N'-methylenebisacrylamide, hydrazine peroxide, diallyl phthalate, divinylbenzene, diisocyanate, dicumyl peroxide, di-tert-butyl peroxide, and styrene.

[0015] Preferably, in step S3, the temperature of the free radical polymerization reaction is 30~100℃ and the time is 2~10h.

[0016] An amphoteric polymer hydrogel was prepared by the method described above; the conductivity of the hydrogel is 0.72~1.58 S / m.

[0017] The above-mentioned zwitterionic polymer hydrogel is used in the preparation of flexible biosensors.

[0018] Compared with the prior art, the present invention has the following beneficial technical effects:

[0019] This invention discloses a method for preparing zwitterionic polymer hydrogels. The method employs a one-pot process, in which reactive monomers [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfonylpropyl)ammonium hydroxide (SBMA), N-[tris(hydroxymethyl)methyl]acrylamide (THMA), and acrylamide (AM) are subjected to free radical polymerization under the initiator and crosslinking agent. The dipole-dipole interactions and non-covalent interactions between polymer chains contribute to their adhesive properties. Simultaneously, the zwitterionic polymer hydrogel exhibits good electrical conductivity. Flexible biosensors prepared from this zwitterionic polymer hydrogel have broad application prospects in healthcare management and wound monitoring. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram illustrating a method for preparing a zwitterionic polymer hydrogel according to the present invention;

[0022] Figure 2 The adhesion strength of zwitterionic polymer sensors prepared in different embodiments is shown in (a) the adhesion performance test curve of STA hydrogel on different materials; (b) digital photographs of the adhesion of STA hydrogel on different materials; and (c) the adhesion performance test curve of STA hydrogel on pigskin.

[0023] Figure 3 The mechanical properties of zwitterionic polymer hydrogels prepared in different embodiments are shown in the figure, where (a) is the tensile curve of different STA hydrogels; and (b) is the fracture strength and fracture strain of different STA hydrogels.

[0024] Figure 4a The conductivity of STA hydrogels prepared in different embodiments;

[0025] Figure 4b Hydrogels were used as cardiac patches to monitor human electrocardiograms.

[0026] Figure 4c This is a detailed image of an electrocardiogram (ECG).

[0027] Figure 5 (a) shows the electrical signal monitoring results of mice on the third day of wound recovery, and (b) shows the electrical signal monitoring results of mice on the seventh day of wound recovery.

[0028] Figure 6 The effect of zwitterionic hydrogels on wound healing. Detailed Implementation

[0029] To enable those skilled in the art to understand the features and effects of the present invention, the terms and expressions used in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding the present invention, and in case of conflict, the definitions in this specification shall prevail.

[0030] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.

[0031] In this document, all features defined by numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible sub-ranges and individual numerical values ​​(including integers and fractions) within those ranges.

[0032] In this article, unless otherwise specified, “contains,” “includes,” “containing,” “has,” or similar terms cover the meanings of “composed of” and “mainly composed of,” for example, “A contains a” covers the meanings of “A contains a and others” and “A contains only a.”

[0033] For the sake of brevity, not all possible combinations of the technical features in each implementation scheme or embodiment are described herein. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each implementation scheme or embodiment can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification.

[0034] like Figure 1 As shown, this invention provides a method for preparing zwitterionic polymer hydrogels, comprising the following steps:

[0035] S1: Dissolve THMA in water, stir and disperse to form a THMA suspension; THMA has poor solubility in water, and the solid particles cannot dissolve after exceeding a certain solid content, and heating can accelerate its dissolution rate. Preferably, the heating temperature is 30~200℃.

[0036] In step S1, the ratio of THMA to water is (10~100):300, based on mass fraction.

[0037] S2: Add AM, SBMA, initiator and crosslinking agent to the THMA suspension, stir evenly to obtain the precursor liquid;

[0038] In step S2, the molar ratio of SBMA to THMA is (1~9):(9~1).

[0039] Preferably, the molar ratio of SBMA to THMA is 6:4.

[0040] According to mass fraction, in step S2, the ratio of AM, SBMA, initiator and crosslinking agent is 20:(20~150):6:1.

[0041] In step S2, the initiator is at least one selected from ammonium persulfate, potassium persulfate, azobisisobutylamidine hydrochloride, azobisisobutylimidazoline hydrochloride, azodicyanovalerate, and azobisisopropylimidazoline. The initiator accounts for 6% of the total mass of all monomers.

[0042] The crosslinking agent is at least one selected from polyethylene glycol diglycidyl ether, N,N'-methylenebisacrylamide, hydrazine peroxide, diallyl phthalate, divinylbenzene, diisocyanate, dicumyl peroxide, di-tert-butyl peroxide, and styrene. The crosslinking agent accounts for 0.6% of the total mass of all monomers.

[0043] S3: The precursor fluid undergoes a free radical polymerization reaction to obtain the zwitterionic polymer hydrogel, which can be labeled STA. The free radical polymerization reaction is carried out at a temperature of 30–200°C for 2–10 hours. The structural formula of the obtained hydrogel is:

[0044]

[0045] Where m, n, and g are all between 400 and 6667.

[0046] The present invention also discloses an amphoteric polymer hydrogel prepared by the above method, wherein the molecular weight of the hydrogel is 30,000 to 500,000. The hydrogel has an electrical conductivity of 0.72 to 1.58 S / m, an adhesion strength of 13.1 to 14.5 kPa, and a tensile strength of 1400% to 1500%.

[0047] This invention also discloses the application of the aforementioned zwitterionic polymer hydrogel in the fabrication of flexible biosensors. This flexible biosensor enables integrated monitoring of patient diagnosis, treatment, and rehabilitation.

[0048] This invention employs a one-pot method to radically polymerize the monomers [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfonylpropyl)ammonium hydroxide (SBMA), N-[tris(hydroxymethyl)methyl]acrylamide (THMA), and acrylamide (AM) under the influence of an initiator and a crosslinking agent. The dipole-dipole interactions and non-covalent interactions between the polymer chains contribute to their adhesive properties. Flexible biosensors made from ion-conductive hydrogels show great promise for applications in healthcare management and wound monitoring.

[0049] The zwitterionic [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfonic acid propionic)ammonium hydroxide (SBMA) selected in this invention has strong dipolarity, and the association between its polymer chains provides physical crosslinking, thereby enhancing the mechanical properties of the hydrogel sensor. The reactive monomer N-[tris(hydroxymethyl)methyl]acrylamide (THMA) provides triple hydrogen bonds and load sharing effect, further improving adhesion. By selecting SBMA, THMA, and AM as reactive monomers and polyethylene glycol diglycidyl ether (PEGDE) as a crosslinking agent, the zwitterionic polymer hydrogel sensor prepared by free radical polymerization exhibits excellent adhesion and mechanical properties, successfully solving the problem of adhesion.

[0050] The material preparation process of this invention is carried out under mild reaction conditions, without the need for high temperature and high pressure, making it safe, environmentally friendly, and low-cost, suitable for mass production. The prepared zwitterionic hydrogel exhibits rapid gelation and high adhesive strength, making it suitable for wound adhesion, hemostasis, and repair, and easy to use. The resulting sensor possesses good conductivity and flexibility. Based on the dipole-dipole interaction in zwitterionic polymers, the designed hydrogel smart sensor exhibits high sensitivity, rapid response, and good stability, effectively monitoring human diseases and recovery. Utilizing the phenomenon of local temperature rise caused by wound inflammation, the highly sensitive hydrogel smart sensor can record electrical signals during the wound healing process, analyze temperature changes to determine the degree of wound inflammation, and promote wound healing, achieving integrated intelligent monitoring of human "diagnosis, treatment, and recovery."

[0051] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0052] The following examples use instruments and equipment conventional in the art. Experimental methods in the following examples, unless otherwise specified, are generally performed under conventional conditions or as recommended by the manufacturer. All raw materials used in the following examples are conventional commercially available products with specifications conventional in the art. In this specification and the following examples, unless otherwise specified, "%" refers to weight percentage, "parts" refers to parts by weight, and "ratio" refers to weight proportion.

[0053] Example 1

[0054] First, 90 parts of N-[tris(hydroxymethyl)methyl]acrylamide (THMA) were added to 300 parts of deionized water, and a uniform THMA suspension A was obtained by magnetic stirring; then, 20 parts of the reactive monomer acrylamide (AM) and 20 parts of SBMA (nSBMA :n THMA =1:9), 6 parts of initiator ammonium persulfate (APS) and 1 part of polyethylene glycol diglycidyl ether (PEGDE) were added to THMA suspension A. The mixture was stirred while adding the reagents to obtain a homogeneous precursor solution B. Finally, the precursor solution B was transferred to a glass plate mold and reacted at 50°C for 4 h to allow it to undergo free radical polymerization and obtain zwitterionic polymer hydrogels with a molecular weight of 30,000 to 500,000.

[0055] Example 2

[0056] First, 80 parts of N-[tris(hydroxymethyl)methyl]acrylamide (THMA) were added to 300 parts of deionized water, and a uniform THMA suspension A was obtained by magnetic stirring; then, 20 parts of the reactive monomer acrylamide (AM) and 30 parts of SBMA (n SBMA :n THMA =2:8), 6 parts of initiator ammonium persulfate (APS) and 1 part of polyethylene glycol diglycidyl ether (PEGDE) were added to THMA suspension A. The mixture was stirred while adding the reagents to obtain a homogeneous precursor solution B. Finally, the precursor solution B was transferred to a glass plate mold and reacted at 50°C for 4 h to allow it to undergo free radical polymerization and obtain an amphoteric polymer hydrogel with a molecular weight of 30,000 to 500,000.

[0057] Example 3

[0058] First, 70 parts of N-[tris(hydroxymethyl)methyl]acrylamide (THMA) were added to 300 parts of deionized water, and a uniform THMA suspension A was obtained by magnetic stirring; then, 20 parts of the reactive monomer acrylamide (AM) and 50 parts of SBMA (n SBMA :n THMA =3:7), 6 parts of initiator ammonium persulfate (APS) and 1 part of polyethylene glycol diglycidyl ether (PEGDE) were added to THMA suspension A. The mixture was stirred while adding the reagents to obtain a homogeneous precursor solution B. Finally, the precursor solution B was transferred to a glass plate mold and reacted at 50°C for 5 h to allow it to undergo free radical polymerization and obtain zwitterionic polymer hydrogels with a molecular weight of 30,000 to 500,000.

[0059] Example 4

[0060] First, 60 parts of N-[tris(hydroxymethyl)methyl]acrylamide (THMA) were added to 300 parts of deionized water, and a homogeneous THMA suspension A was obtained by magnetic stirring. Then, 20 parts of the reactive monomer acrylamide (AM), 70 parts of SBMA (SBMA:THMA molar ratio of 4:6), 6 parts of the initiator ammonium persulfate (APS), and 1 part of polyethylene glycol diglycidyl ether (PEGDE) were added to THMA suspension A, and stirring was performed while adding the reagents to obtain a homogeneous precursor solution B. Finally, precursor solution B was transferred to a glass plate mold and reacted at 50°C for 5 h to allow free radical polymerization, resulting in an amphoteric polymer hydrogel with a molecular weight of 30,000 to 500,000.

[0061] Example 5

[0062] First, 50 parts of N-[tris(hydroxymethyl)methyl]acrylamide (THMA) were added to 300 parts of deionized water, and a uniform THMA suspension A was obtained by magnetic stirring; then, 20 parts of the reactive monomer acrylamide (AM) and 80 parts of SBMA (n SBMA :n THMA The ratio of 5:5 was used to add 6 parts of ammonium persulfate (APS) initiator and 1 part of polyethylene glycol diglycidyl ether (PEGDE) to THMA suspension A. The mixture was stirred while adding the reagents to obtain a homogeneous precursor solution B. Finally, the precursor solution B was transferred to a glass plate mold and reacted at 50°C for 5 h to allow it to undergo free radical polymerization and obtain an amphoteric polymer hydrogel with a molecular weight of 30,000 to 500,000.

[0063] Table 1 shows the performance test results of the hydrogels prepared in Examples 1-5 of this invention, specifically:

[0064] Table 1 Summary of Performance of Different Samples

[0065]

[0066] Figure 2 In Figure (a), the adhesion curves of the hydrogel prepared in this invention on different substrates are shown, namely rubber, planks, paper, iron and plastic. Figure 2 (b) shows the adhesion of the hydrogel prepared in this invention on different substrates, including glass. As can be seen from the figure, the adhesion strength of STA hydrogel on rubber, wood, paper, iron sheet and plastic is 9.7, 16.3, 16.7, 28.0 and 35.7 kPa, respectively. Figure 2(c) shows the adhesion performance test curves of different hydrogels prepared in the embodiments of the present invention on pig skin. As can be seen from the figure, the maximum adhesion force of the STA hydrogel prepared in the present invention on pig skin tissue is 13.5 kPa. In summary, the STA hydrogel prepared in the present invention exhibits strong adhesion on the surface of various materials.

[0067] Figure 3 The figures show the mechanical properties of zwitterionic polymer hydrogels from different embodiments. Mechanical toughness enables human tissue to perform motor functions and is a crucial factor determining the biological function of oligomeric hydrogels; therefore, hydrogel biosensors must possess flexibility. (a) shows the tensile curves of different STA hydrogels. As can be seen, the tensile strength of the hydrogel increases with increasing SBMA content. (b) shows the tensile strength and fracture strain of different STA hydrogels. As can be seen, with increasing SBMA content, the tensile strength gradually increases from 24 kPa to 46 kPa, and the fracture strain gradually increases from 368% to 1487%. These results indicate that the introduction of SBMA enhances the mechanical properties of the STA hydrogel. This is attributed to the formation of the polymer network and the increase in non-covalent interactions within the STA hydrogel.

[0068] Figure 4a The figure shows the conductivity of the STA hydrogel. As can be seen from the figure, the PolySBMA polymer containing anionic and cationic groups has dipole-dipole interactions, which can promote the transport of charged particles along the main chain, thereby improving the conductivity of the hydrogel. The impedance of the STA hydrogel was measured by electrochemical impedance spectroscopy (EIS). The conductivity of the STA hydrogel is between 0.72 and 1.58 S / m.

[0069] Figure 4b As shown in the figure, when using the STA hydrogel sensor to diagnose ECG signals, its accuracy and stability are highly similar to those of commercially available gel electrodes.

[0070] Figure 4c The image shows a detailed electrocardiogram (ECG) image. As can be seen from the figure, the ECG signal intensity displayed by the STA Z-hydrogel is 1.14 times that of commercial gel electrodes, while the signal response time is only 38.99 milliseconds, indicating its excellent signal response capability. Therefore, in addition to having good mechanical and adhesive properties, the STA hydrogel in this invention also exhibits good ionic conductivity in the absence of inorganic salts.

[0071] Figure 5The data shows the monitoring performance of the hydrogel on the wound site. (a) shows the electrical signal monitoring on the third day of wound recovery in mice, and (b) shows the electrical signal monitoring on the seventh day of wound recovery in mice. As shown in the figure, on the third day, the relative change in resistance (ΔR / R0) between the wound site and the blank control group was 16.09±2.49%. On the seventh day, the relative change in resistance (ΔR / R0) between the wound group and the control group decreased to 2.33±0.73%. Therefore, STA Z-hydrogel can be used as a biosensor to successfully track wound healing by monitoring the temperature of the wound site.

[0072] Figure 6 This study investigated the wound recovery effect of zwitterionic hydrogels on wound healing. The healing efficiency of STA hydrogels in wounds was assessed using a mouse model of full-thickness skin defects. Details of the STA hydrogel wound treatment process are provided in the experimental section. As shown in the figure, on day 7, although reepithelialization occurred in all groups, the wound healing in the STA hydrogel group was significantly higher than that in the control group and the commercial Duoderm group. Notably, on day 10, the tissue in the STA hydrogel group showed significant contraction, while the control group still showed extensive crusting. Furthermore, after 14 days of wound treatment, the wound closure rate in the STA hydrogel group reached almost 100%.

[0073] Example 6

[0074] A method for preparing an amphoteric polymer hydrogel includes the following steps:

[0075] S1: Dissolve THMA in water, stir and disperse to form a THMA suspension; THMA has poor solubility in water, and the solid particles cannot dissolve after exceeding a certain solid content, and heating can accelerate its dissolution rate, preferably at a heating temperature of 30°C; wherein, the ratio of THMA to water by mass fraction is 100:300.

[0076] S2: Add AM, SBMA, initiator and crosslinking agent to the THMA suspension and stir evenly to obtain a precursor fluid; wherein the molar ratio of SBMA to THMA is 1:9, and the ratio of AM, SBMA, initiator and crosslinking agent by mass fraction is 20:20:6:1.

[0077] S3: The precursor fluid undergoes a free radical polymerization reaction to obtain the zwitterionic polymer hydrogel, which can be labeled STA. The free radical polymerization reaction is carried out at a temperature of 30°C for 10 hours.

[0078] Example 7

[0079] A method for preparing an amphoteric polymer hydrogel includes the following steps:

[0080] S1: Dissolve THMA in water, stir and disperse to form a THMA suspension; THMA has poor solubility in water, and the solid particles cannot dissolve after exceeding a certain solid content, and heating can accelerate its dissolution rate, preferably, the heating temperature is 200°C; wherein, the ratio of THMA to water by mass fraction is 10:300.

[0081] S2: Add AM, SBMA, initiator and crosslinking agent to the THMA suspension, stir evenly to obtain a precursor fluid; wherein, the molar ratio of SBMA to THMA is 9:1, and the ratio of AM, SBMA, initiator and crosslinking agent by mass fraction is 20:150:6:1.

[0082] S3: The precursor fluid undergoes a free radical polymerization reaction to obtain the zwitterionic polymer hydrogel, which can be labeled STA. The free radical polymerization reaction is carried out at a temperature of 200°C for 2 hours.

[0083] Example 8

[0084] A method for preparing an amphoteric polymer hydrogel includes the following steps:

[0085] S1: Dissolve THMA in water, stir and disperse to form a THMA suspension; THMA has poor solubility in water, and the solid particles cannot dissolve after exceeding a certain solid content, and heating can accelerate its dissolution rate, preferably, the heating temperature is 100°C; wherein, the ratio of THMA to water by mass fraction is 40:300.

[0086] S2: Add AM, SBMA, initiator and crosslinking agent to the THMA suspension, stir evenly to obtain a precursor fluid; wherein, the molar ratio of SBMA to THMA is 6:4, and the ratio of AM, SBMA, initiator and crosslinking agent by mass fraction is 20:100:6:1.

[0087] S3: The precursor fluid undergoes a free radical polymerization reaction to obtain the zwitterionic polymer hydrogel, which can be labeled STA. The free radical polymerization reaction is carried out at 100°C for 5 hours.

[0088] This invention presents the first method for synthesizing an integrated "diagnosis, treatment, and rehabilitation" smart sensor based on a zwitterionic polymer hydrogel. Its advantages lie in the introduction of N-[tris(hydroxymethyl)methyl]acrylamide (THMA), which provides triple hydrogen bonds and load-sharing effects to the polymer hydrogel adhesive structure, resulting in stronger adhesion. Simultaneously, [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA) possesses strong dipolarity; its interchain association provides physical crosslinking to enhance the mechanical properties of the adhesive, while its dipole-dipole interactions promote charged ion transport within the polymer, endowing the hydrogel with electrical conductivity. This hydrogel not only promotes wound healing but also achieves integrated "diagnosis, treatment, and rehabilitation" monitoring by monitoring the electrical signal changes caused by temperature increases resulting from inflammation during wound healing.

[0089] This invention discloses a method for preparing an integrated diagnostic, therapeutic, and remedial intelligent sensor based on zwitterionic polymer hydrogels. The method employs a one-pot process, involving the free radical polymerization of the monomers [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfonylpropyl)ammonium hydroxide (SBMA), N-[tris(hydroxymethyl)methyl]acrylamide (THMA), and acrylamide (AM) under the influence of an initiator and a crosslinking agent. This invention solves the problem of existing conductive hydrogel sensors being unable to simultaneously achieve both adhesive and conductive properties, thus enabling its wide application in the field of health monitoring.

[0090] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a zwitterionic polymer hydrogel, characterized in that, Includes the following steps: S1: Dissolve THMA in water, stir and disperse to form a THMA suspension; S2: Add AM, SBMA, initiator and crosslinking agent to the THMA suspension, stir evenly to obtain the precursor liquid; S3: The precursor fluid is subjected to a free radical polymerization reaction to obtain the zwitterionic polymer hydrogel. According to the mass fraction, in step S1, the ratio of THMA to water is (10~100):300; In step S2, the molar ratio of SBMA to THMA is 6:4; According to mass fraction, in step S2, the ratio of AM, SBMA, initiator and crosslinking agent is 20:100:6:1; In step S2, the crosslinking agent is polyethylene glycol diglycidyl ether; In step S3, the temperature of the free radical polymerization reaction is 30~100℃ and the time is 2~10h.

2. The method for preparing an amphoteric polymer hydrogel according to claim 1, characterized in that, In step S2, the initiator is at least one of ammonium persulfate, potassium persulfate, azobisisobutylamidine hydrochloride, azobisisobutylimidazoline hydrochloride, azobisisobutylammonium valerate, and azobisisopropylimidazoline.

3. A zwitterionic polymer hydrogel, characterized in that, The hydrogel is prepared by the method described in any one of claims 1 to 2; the hydrogel has an electrical conductivity of 0.72 to 1.58 S / m, an adhesion strength of 13.1 to 14.5 KPa, and a fracture strain of 1400% to 1500%.

4. The application of the zwitterionic polymer hydrogel as described in claim 3 in the preparation of flexible biosensors.

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