A method for preparing a janus asymmetric wet-adhesive hydrogel based on electrostatic field
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-05-04
- Publication Date
- 2026-08-11
AI Technical Summary
这种黏连十分不利于伤口的恢复和生物体的正常活动
[0026](1)本发明的Janus湿粘附水凝胶制备方法，工艺简单，可适用于工业化生产。
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Figure CN116813945B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of smart materials and hydrogel technology, specifically relating to a method for preparing Janus asymmetric wet adhesion hydrogels based on an electrostatic field. Background Technology
[0002] Hydrogels are three-dimensional network polymers with high water content. Due to their excellent biocompatibility, ease of modification, and high water content, they are widely used in the biomedical field. Hydrogels that impart adhesive properties are commonly used as tissue adhesives, wound dressings, hemostatic materials, and drug-eluting materials. Because water is present on the surface of living organisms, a hydration layer forms on the tissue surface, hindering the contact between adhesive molecules and the tissue. Therefore, the development of wet adhesion hydrogels plays a crucial role in their application in the biological field (Nature, 2019, 575, 169; Advanced Functional Materials, 2020, 30; Advanced Materials, 2023, DOI: 10.1002 / adma.202300394e2300394).
[0003] Several methods exist to improve the wet adhesion of hydrogel materials, such as increasing the material's hydrophobicity and removing moisture at the interface by pressing, or increasing the material's absorbency to absorb moisture at the interface and provide a drier application environment. While these methods solve the problems associated with the hydration layer, they also result in uniform wet adhesion of the gel. This property means that the material not only adheres to the wound but also binds to the tissue fluid on the other side. This adhesion is highly detrimental to wound healing and normal bodily functions. Summary of the Invention
[0004] To address the aforementioned problems in existing technologies, the present invention aims to provide a method for preparing Janus asymmetric wet adhesion hydrogels based on an electrostatic field. This method employs an integrated approach to prepare asymmetric wet adhesion hydrogels for use as tissue bio-adhesives to prevent postoperative adhesions.
[0005] To solve the above problems, the technical solution adopted by the present invention is as follows:
[0006] A method for preparing Janus asymmetric wet adhesion hydrogel based on an electrostatic field: First, an alkenyl catechol molecule (Vin-DOPA), an alkenyl hydrophobic molecule (Vin-Coa), acrylic acid, a crosslinking agent, an initiator, and biomacromolecules are stirred and mixed in water to obtain a hydrogel solution. Then, the solution is poured into a mold and allowed to stand to allow the gel molecules to aggregate at the bottom. The mold is then placed in an electrostatic field environment for treatment. Finally, ultraviolet crosslinking and curing are performed to obtain the Janus asymmetric wet adhesion hydrogel.
[0007] A method for preparing asymmetric wet adhesion hydrogels based on an integrated electrostatic field for use as tissue bio-adhesives to prevent postoperative adhesions includes the following steps:
[0008] 1) Catechol small molecules with amino and propenyl groups (Vin-DOPA) are prepared by dehydration reaction of enol molecules and amino-containing catechol molecules. The amino groups on the catechol monomers can be protected with protecting groups first and then deprotected after the reaction.
[0009] 2) Prepare hydrophobic condensed molecules (Vin-Coa) by reacting olefinic monomers with hydrophobic small molecules;
[0010] 3) Add Vin-DOPA and acrylic acid in a mass ratio of 1:0.1-5 to an aqueous solution, then add Vin-Coa in a mass ratio of 0.1-1, and then add crosslinking agent, initiator and biomacromolecule in a mass ratio of 0.01-0.1:0.005-0.5:0.005-0.5 to the solution. Then stir the mixed solution at room temperature for 1-120 minutes, put it into a transparent and sealed glass mold and let it stand for 1-120 minutes.
[0011] 4) Place the mold from step 3) under the electrostatic device, and place conductive layers on the top and bottom sides of the mold and connect them to the power source;
[0012] 5) Turn on the electrostatic field to allow the anions and cations in the solution in the mold to move under the action of the electrostatic field. Maintain the electrostatic field for 1-120 minutes.
[0013] 6) Turn on the ultraviolet light to solidify the gel solution for 10-120 minutes to obtain an asymmetric wet adhesion hydrogel.
[0014] The mass ratio of Vin-DOPA, Vin-Coa, acrylic acid, biomacromolecule, crosslinking agent and initiator is 1:0.1 to 1:0.1 to 5:0.01 to 0.1:0.005 to 0.5:0.005 to 0.5.
[0015] The biomacromolecules mentioned are one or more of chitosan, gelatin, hyaluronic acid, starch, and cellulose.
[0016] The initiator is one of benzoin dimethyl ether, diphenyl ethyl ketone, benzophenone, and diisobutylamidine hydrochloride.
[0017] The crosslinking agent is one or a mixture of several of N,N-methylenebisacrylamide, vinyl-POSS, and polyethylene glycol diacrylate.
[0018] The Vin-DOPA is an amino-retaining enyl catechol molecule prepared using enol molecules and amino-containing catechol molecules; wherein the enol molecules are selected from one or more of allyl alcohol, methacryl alcohol, butenol, and ethylbutenol.
[0019] Vin-Coa is a hydrophobic condensed molecule prepared by reacting an olefinic monomer with a hydrophobic small molecule; wherein the olefinic monomer is selected from one or more of acrylic acid, methacrylic acid and butenoic acid, and the hydrophobic small molecule is selected from one or more of dodecyl alcohol, octadecyl alcohol and bis(2-methoxyethyl)amine.
[0020] The mold is a transparent glass container with a thickness of 0.2-2 nm. The bottom of the mold is connected to the negative terminal of a DC power supply via a copper plate, and the top is connected to the positive terminal of the power supply via a transparent conductive layer.
[0021] The hydrogel solution is placed in the mold for less than 120 minutes to allow the condensing molecules to aggregate at the bottom; then it is treated in an electrostatic field for less than 120 minutes, and finally the hydrogel solution is cured into a gel by turning on the ultraviolet lamp.
[0022] The hydrogel prepared in this invention exhibits asymmetric wet adhesion properties, with strong adhesion strength at the bottom and weak adhesion strength at the top. Vin-DOA molecules carrying amino cations are migrated to the bottom of the gel using an electric field. The synergistic effect of catechol-cations increases the wet adhesion properties of the material, and the spontaneous aggregation of temperature-sensitive self-aggregating molecules at the bottom further enhances the wet adhesion effect at the bottom of the gel. However, the top of the material, due to the reduction of adhesive groups and the aggregation of acid radicals and ions, carries a large number of negative charges on its surface, creating a repulsive force with the negative charges on the tissue surface, resulting in only a weak adhesion effect.
[0023] This invention provides a novel integrated method for preparing asymmetric Janus hydrogels, which is more convenient and suitable for industrial production compared to the traditional multilayer composite method for preparing Janus gels.
[0024] This invention can further improve the adhesion strength of wet adhesive gels. Since cations can migrate to the bottom of the hydrogel by applying an electric field, grafting adhesive molecules (such as L-DOPA groups and NHS groups) onto monomers with amino and alkenyl groups allows the amino cations to migrate to the bottom of the solution via an electric field. Adjacent adhesive molecules are also carried to the bottom of the solution, and curing then concentrates a large number of adhesive molecules at the bottom of the gel. This method can further enhance the wet adhesion strength of existing adhesive materials.
[0025] Beneficial effects: Compared with the prior art, the advantages of this invention are:
[0026] (1) The Janus wet adhesion hydrogel preparation method of the present invention is simple and applicable to industrial production.
[0027] (2) The Janus wet adhesion hydrogel provided by the present invention has good mechanical properties, and has the advantages of weak adhesion at the top and strong wet adhesion at the bottom. In addition to being widely used in biomedical fields such as biological adhesives and wound dressings, it also has potential applications in fields such as smart sensors and flexible electronic devices. Attached Figure Description
[0028] Figure 1 This is the NMR spectrum of the prepared Vin-DOPA;
[0029] Figure 2 This is the NMR spectrum of the prepared Vin-Coa;
[0030] Figure 3 This is a graph showing the adhesion performance of Janus wet adhesion hydrogel;
[0031] Figure 4 This diagram shows the distribution of Vin-DOPA in aqueous solution, using fluorescent amino molecules instead of Vin-DOPA. Detailed Implementation
[0032] The present invention will be further described below with reference to specific embodiments.
[0033] Preparation of typical Vin-DOPA: 1 eq of L-DOPA solution was added to a dioxane solution, and the pH was adjusted to 9 with NaOH. Then, 1 eq of di-tert-butyl dicarbonate was added to protect the amino group. After reacting at room temperature for 24 h, rotary evaporation was performed to obtain product 1. 1 eq of product 1 and 1 eq of allyl alcohol were dissolved in dichloromethane solution, and 2 eq of EDC-HCl were added. The mixture was reacted at 50 °C for 6 h, and the solution was washed to obtain product 2. 1 eq of product 2 was dissolved in dichloromethane solution, and 1 eq of trifluoroacetic acid was added. After stirring at room temperature for 6 h, rotary evaporation was performed to obtain product Vin-DOPA. The NMR spectrum of the prepared Vin-DOPA is shown below. Figure 1 As shown. In the following examples, the method was used to prepare the corresponding Vin-DOPA by changing the monomer.
[0034] Preparation of typical Vin-Coa: 1 eq of bis(2-methoxyethyl)amine and 1 eq of acrylic acid were dissolved in dichloromethane, and 1 eq of triethylamine was added. The mixture was stirred at low temperature for 6 h. Water was added to the solvent, and after extraction with dichloromethane, Vin-Coa was obtained by rotary evaporation. The NMR spectrum of the prepared Vin-Coa is shown below. Figure 2 As shown. In the following examples, the method was used to prepare the corresponding Vin-Coa by changing the monomer.
[0035] Example 1
[0036] 1g of Vin-DOPA (synthesized from allyl alcohol and L-DOPA) and 2g of acrylic acid were added to 10mL of aqueous solution, followed by 0.1g of Vin-Coa (synthesized from acrylic acid and dodecanol). Then, 0.1g of gelatin, 0.01g of vinyl-POSS, and 0.01g of benzoin dimethyl ether were added to the solution. After stirring at room temperature for 20min, the mixture was poured into a transparent mold. The mold was allowed to stand at room temperature for 40min before being placed in an electrostatic field. Conductive layers were connected to both sides of the mold, and the electrostatic field was then turned on, with the voltage adjusted to 5000V for 60min. A 20W, 365nm UV lamp was used for curing, resulting in Janus hydrogel after 30min.
[0037] Example 2
[0038] 0.5 g of Vin-DOPA (synthesized from allyl alcohol and L-DOPA) and 2 g of acrylic acid were added to 12 mL of aqueous solution, followed by 0.1 g of Vin-Coa (synthesized from methacrylic acid and bis(2-methoxyethyl)amine). Then, 0.05 g of chitosan, 0.02 g of vinyl-POSS, and 0.01 g of benzoin dimethyl ether were added to the solution. After stirring at room temperature for 150 min, the solution was poured into a transparent mold. The mold was allowed to stand at room temperature for 70 min, then placed in an electrostatic field. Conductive layers were connected to both sides of the mold, and the electrostatic field was turned on, adjusting the voltage to 4000 V for 30 min. A 20 W, 365 nm UV lamp was used for curing, resulting in Janus hydrogel after 20 min.
[0039] Example 3
[0040] 1 g of Vin-DOPA (synthesized from allyl alcohol and levodopa) and 3 g of acrylic acid were added to 12 mL of aqueous solution, followed by 0.15 g of Vin-Coa (synthesized from methacrylic acid and bis(2-methoxyethyl)amine). Then, 0.1 g of cellulose, 0.01 g of N,N-methylenebisacrylamide, and 0.01 g of diphenyl ethyl ketone were added to the solution. After stirring at room temperature for 20 min, the solution was poured into a transparent mold. The mold was allowed to stand at room temperature for 30 min, then placed in an electrostatic field. Conductive layers were connected to both sides of the mold, and the electrostatic field was turned on, with the voltage adjusted to 3000 V for 20 min. A 20 W, 365 nm UV lamp was used for curing, resulting in Janus hydrogel after 10 min.
[0041] Example 4
[0042] 1g of Vin-DOPA (synthesized from methacrylic acid and levodopa) and 2g of acrylic acid were added to 10mL of aqueous solution, followed by 0.05g of Vin-Coa (synthesized from methacrylic acid and octadecylamine). Then, 0.1g of gelatin, 0.02g of N,N-methylenebisacrylamide, and 0.02g of diphenyl ethyl ketone were added to the solution. After stirring at room temperature for 30min, the mixture was poured into a transparent mold. The mold was allowed to stand at room temperature for 50min, then placed in an electrostatic field. Conductive layers were connected to both sides of the mold, and the electrostatic field was turned on, adjusting the voltage to 6000V for 100min. A 20W, 365nm UV lamp was used for curing, resulting in Janus hydrogel after 40min.
[0043] Example 5
[0044] 1g of Vin-DOPA (synthesized from butenol and levodopa) and 3g of acrylic acid were added to 15mL of aqueous solution, followed by 0.1g of Vin-Coa (synthesized from acrylic acid and bis(2-methoxyethyl)amine). Then, 0.1g of hyaluronic acid, 0.02g of polyethylene glycol diacrylate, and 0.02g of diphenyl ethyl ketone were added to the solution. After stirring at room temperature for 10min, the solution was poured into a transparent mold. The mold was allowed to stand at room temperature for 10min, then placed in an electrostatic field. Conductive layers were connected to both sides of the mold, and the electrostatic field was turned on, adjusting the voltage to 7000V for 20min. A 20W, 365nm UV lamp was used for curing, resulting in Janus hydrogel after 10min.
[0045] Example 6
[0046] 1 g of Vin-DOPA (synthesized from butenol and levodopa) and 2 g of acrylic acid were added to 12 mL of aqueous solution, followed by 0.15 g of Vin-Coa (synthesized from methacrylic acid and bis(2-methoxyethyl)amine). Then, 0.05 g of starch, 0.02 g of polyethylene glycol diacrylate, and 0.02 g of diphenyl ethyl ketone were added to the solution. After stirring at room temperature for 15 min, the solution was poured into a transparent mold. The mold was allowed to stand at room temperature for 10 min, then placed in an electrostatic field. Conductive layers were connected to both sides of the mold, and the electrostatic field was turned on, with the voltage adjusted to 10000 V for 50 min. A 20 W, 365 nm UV lamp was used for curing, resulting in Janus hydrogel after 30 min.
[0047] Example 7
[0048] 1g of Vin-DOPA (synthesized from butenol and levodopa) and 2g of acrylic acid were added to 10mL of aqueous solution, followed by 0.1g of Vin-Coa (synthesized from methacrylic acid and dodecylamine). Then, 0.1g of chitosan, 0.02g of polyethylene glycol diacrylate, and 0.02g of diisobutylamidine hydrochloride were added to the solution. After stirring at room temperature for 60min, the mixture was poured into a transparent mold. The mold was allowed to stand at room temperature for 40min before being placed in an electrostatic field. Conductive layers were connected to both sides of the mold, and the electrostatic field was then turned on, with the voltage adjusted to 7000V for 60min. A 20W, 365nm UV lamp was used for curing, resulting in Janus hydrogel after 100min.
[0049] Example 8
[0050] 1 g of Vin-DOPA (synthesized from butenol and levodopa) and 2 g of acrylic acid were added to 12 mL of aqueous solution, followed by 0.15 g of Vin-Coa (synthesized from methacrylic acid and octadecylamine). Then, 0.1 g of gelatin, 0.02 g of vinyl-POSS, and 0.01 g of diisobutylamidine hydrochloride were added to the solution. After stirring at room temperature for 20 min, the solution was poured into a transparent mold. The mold was allowed to stand at room temperature for 40 min, then placed in an electrostatic field. Conductive layers were connected to both sides of the mold, and the electrostatic field was turned on, with the voltage adjusted to 4000 V for 70 min. A 20 W, 365 nm UV lamp was used for curing, resulting in Janus hydrogel after 60 min.
[0051] Example 9
[0052] 1 g of Vin-DOPA (synthesized from methacrylic acid and levodopa) and 3 g of acrylic acid were added to 15 mL of aqueous solution, followed by 0.15 g of Vin-Coa (synthesized from methacrylic acid and dodecylamine). Then, 0.1 g of gelatin, 0.02 g of vinyl-POSS, and 0.01 g of diisobutylamidine hydrochloride were added to the solution. After stirring at room temperature for 60 min, the solution was poured into a transparent mold. The mold was allowed to stand at room temperature for 70 min, then placed in an electrostatic field. Conductive layers were connected to both sides of the mold, and the electrostatic field was turned on, with the voltage adjusted to 2000 V for 20 min. A 20 W, 365 nm UV lamp was used for curing, resulting in Janus hydrogel after 20 min.
[0053] Example 10
[0054] 1g of Vin-DOPA (synthesized from allyl alcohol and levodopa) and 3g of acrylic acid were added to 15mL of aqueous solution, followed by 0.05g of Vin-Coa (synthesized from butenoic acid and dodecylamine). Then, 0.1g of cellulose, 0.01g of vinyl-POSS, and 0.01g of diphenyl ethyl ketone were added to the solution. After stirring at room temperature for 30min, the solution was poured into a transparent mold. The mold was allowed to stand at room temperature for 80min before being placed in an electrostatic field. Conductive layers were connected to both sides of the mold, and the electrostatic field was then turned on, with the voltage adjusted to 8000V for 50min. A 20W, 365nm UV lamp was used for curing, resulting in Janus hydrogel after 40min.
[0055] Example 11
[0056] Janus wet adhesion hydrogels prepared in any of Examples 1-10 were subjected to a two-sided wet adhesion strength test: they were bonded to fresh pigskin underwater, removed after 5-20 seconds, and tested on a universal electronic materials testing machine using the ASTM-F2255 (2015) test method. Figure 3 The results are shown in Table 1.
[0057] Table 1 Results of wet adhesion performance test
[0058] Example 1 12 67 Example 2 18 74 Example 3 15 75 Example 4 18 73 Example 5 21 76 Example 6 14 71 Example 7 16 72 Example 8 18 77 Example 9 19 69 Example 10 16 78
[0059] As can be seen from Table 1, Janus hydrogels prepared using this method generally exhibit asymmetric wet adhesion properties and can be used as postoperative anti-adhesion bioadhesives in vivo.
[0060] Example 12
[0061] Method for determining different charges on the top and bottom of the hydrogel: In order to verify that the electrostatic field in this invention can indeed disperse the anions and cations in the gel solution in a certain direction, fluorescent amino molecules were used instead of Vin-DOPA to simulate their distribution in aqueous solution. Janus gels were prepared using voltages of 2000V and 7000V respectively. The fluorescence on both sides of the gel was observed by fluorescence microscopy to confirm the movement of anions and cations under the action of the electric field.
[0062] Figure 4 The figure shows the distribution of Vin-DOPA in aqueous solution using fluorescent amino molecules instead of Vin-DOPA. As can be seen from the figure, the fluorescent spots at the bottom are obvious after the electric field is applied, while the fluorescence intensity at the top is only 10% of that at the bottom. This proves that the fluorescent cations do move in the solution after the electric field is applied and are fixed after gelation.
[0063] Comparative Example 1
[0064] To illustrate how the present invention can alter the distribution of anions and cations in the gel solution by applying an electric field, thereby changing the wet adhesion strength on both sides, the same raw materials and proportions as in Example 2 were used, but the wet adhesion strength of the gel on both sides was tested without applying an electric field. 0.5 g of Vin-DOPA (synthesized from allyl alcohol and levodopa) and 2 g of acrylic acid were added to 12 mL of aqueous solution, followed by 0.1 g of Vin-Coa (synthesized from methacrylic acid and bis(2-methoxyethyl)amine). Then, 0.05 g of chitosan, 0.02 g of vinyl-POSS, and 0.01 g of benzoin dimethyl ether were added to the solution. After stirring at room temperature for 150 min, the solution was poured into a transparent mold. The mold was allowed to stand at room temperature for 70 min, and then cured with a 20 W, 365 nm UV lamp. Janus hydrogel was obtained after 20 min.
[0065] Comparative Example 2
[0066] To illustrate how the invention improves wet adhesion strength by allowing hydrophobic molecules to settle to the bottom through self-aggregation, the same raw materials and proportions as in Example 2 were used. The gel solution was cured without waiting for the hydrophobic molecules to settle, and the wet adhesion strength of both sides of the gel was tested. 0.5g of Vin-DOPA (synthesized from allyl alcohol and L-DOPA) and 2g of acrylic acid were added to 12mL of aqueous solution, followed by 0.1g of Vin-Coa (synthesized from methacrylic acid and bis(2-methoxyethyl)amine). Then, 0.05g of chitosan, 0.02g of vinyl-POSS, and 0.01g of benzoin dimethyl ether were added to the solution. After stirring at room temperature for 150min, the solution was poured into a transparent mold. Without allowing it to stand, conductive layers were directly attached to both sides of the mold. The power switch was then turned on, and the voltage was adjusted to 4000V for 30min. Curing was then performed using a 20W, 365nm UV lamp, resulting in Janus hydrogel after 20min.
[0067] Comparative Example 3
[0068] To illustrate how the present invention improves the wet adhesion strength of materials through the synergistic effect of catechol-cations in Vin-DOPA and the hydrophobic effect of Vin-Coa, the same raw materials and proportions as in Example 2 were used, but without the addition of Vin-DOPA and Vin-Coa. The wet adhesion strength of the gel on both sides was tested. 0.5 g of DOPA (levodopa) and 2 g of acrylic acid were added to 12 mL of aqueous solution. Then, 0.05 g of chitosan, 0.02 g of vinyl-POSS, and 0.01 g of benzoin dimethyl ether were added to the solution. After stirring at room temperature for 150 min, the solution was poured into a transparent mold. Conductive layers were attached to both sides of the mold, and then an electrostatic field was applied, adjusting the voltage to 4000 V for 30 min. Curing was performed using a 20 W, 365 nm UV lamp, resulting in Janus hydrogel after 20 min.
[0069] Table 2 Results of wet adhesion performance test
[0070] Example 2 18 74 Comparative Example 1 56 62 Comparative Example 2 16 65 Comparative Example 3 32 37
[0071] Table 2 shows the wet adhesion performance test results of hydrogels prepared without electrostatic field treatment, without standing before electrostatic field treatment, and without Vin-DOPA and / or Vin-Coa, compared to the hydrogel prepared in Example 2. The results show that Comparative Example 1, without electrostatic field treatment, exhibits similar wet adhesion performance on both sides, while its bottom strength is slightly weaker than that of Example 2. This indicates that applying an electric field can obtain Janus hydrogels and improve the wet adhesion strength at the bottom of the material. Comparative Example 2, without standing before electrostatic field treatment, shows asymmetrical wet adhesion performance, but its bottom wet adhesion strength is lower than that of Example 2. This indicates that the temperature-sensitive self-aggregating layer did not immediately settle to the bottom of the gel when not standing, thus reducing the wet adhesion performance compared to Comparative Example 2. Hydrogels prepared without Vin-DOPA and / or Vin-Coa did not exhibit asymmetric adhesion ability because there was no large amount of anion and cation formation in the solution, and the application of an electric field could not cause an asymmetric distribution of adhesion molecules. Since the adhesion properties on both sides were similar, and since there were no adhesion molecules and a hydrophobic layer, the stickiness of the gel was only provided by the formation of hydrogen bonds by acrylic acid, so the adhesion strength was weaker than that of Example 2.
Claims
1. A method for preparing Janus asymmetric wet adhesion hydrogels based on an electrostatic field, characterized in that: First, Vin-DOPA, Vin-Coa, acrylic acid, crosslinking agent, initiator and biomacromolecules are mixed in water to obtain a hydrogel solution, which is then poured into a mold and left to stand so that the gel molecules gather at the bottom; the mold is then placed in an electrostatic field environment for treatment; and then UV crosslinking and curing are performed to obtain Janus asymmetric wet adhesion hydrogel. Vin-DOPA is a small molecule of enyl catechol that retains the amino group, prepared by using enol molecules and amino-containing catechol molecules; wherein, the enol molecules are selected from one or more of allyl alcohol, methacryl alcohol, butenol, and ethylbutenol. Vin-Coa is a hydrophobic gel molecule prepared by reacting an olefinic monomer with a hydrophobic small molecule; wherein the olefinic monomer is selected from one or more of acrylic acid, methacrylic acid and butenoic acid, and the hydrophobic small molecule is selected from one or more of dodecyl alcohol, octadecyl alcohol and bis(2-methoxyethyl)amine.
2. The method for preparing Janus asymmetric wet adhesion hydrogel based on an electrostatic field according to claim 1, characterized in that: The mass ratio of Vin-DOPA, Vin-Coa, acrylic acid, crosslinking agent, initiator, and biomacromolecule is 1:0.1 to 1:0.1 to 5:0.01 to 0.1:0.005 to 0.5:0.005 to 0.
5.
3. The method for preparing Janus asymmetric wet adhesion hydrogel based on an electrostatic field according to claim 1, characterized in that, The biomacromolecules are selected from one or more of gelatin, chitosan, hyaluronic acid, cellulose, and starch.
4. The method for preparing Janus asymmetric wet adhesion hydrogel based on an electrostatic field according to claim 1, characterized in that, The mold is a transparent glass container with a thickness of 0.2-2nm. The bottom of the mold is connected to the negative terminal of the DC power supply via a copper plate, and the top is connected to the positive terminal of the power supply via a transparent conductive layer.
5. The method for preparing Janus asymmetric wet adhesion hydrogel based on an electrostatic field according to claim 1, characterized in that, The hydrogel solution is placed in the mold for less than 120 minutes to allow the gel molecules to aggregate at the bottom; then it is treated in an electrostatic field for less than 120 minutes, and finally the hydrogel solution is cured into a gel by turning on the ultraviolet lamp.
6. The method for preparing Janus asymmetric wet adhesion hydrogel based on an electrostatic field according to claim 1, characterized in that, Includes the following steps: 1) Vin-DOPA is prepared by dehydration reaction of enol molecules and amino-containing catechol molecules; 2) Vin-Coa was prepared by reacting olefinic monomers with hydrophobic small molecules; 3) Add Vin-DOPA and acrylic acid in a mass ratio of 1:0.1-5 to an aqueous solution, then add Vin-Coa in a mass ratio of 0.1-1, and then add crosslinking agent, initiator and biomacromolecule in a mass ratio of 0.01-0.1:0.005-0.5:0.005-0.5 to the solution. Then stir the mixed solution at room temperature for 1-120 minutes, put it into a transparent and sealed glass mold and let it stand for 1-120 minutes. 4) Place the mold from step 3) under the electrostatic device, and place conductive layers on the top and bottom sides of the mold and connect them to the power source; 5) Turn on the electrostatic field to allow the anions and cations in the solution in the mold to move under the action of the electrostatic field. Maintain the electrostatic field for 1-120 minutes. 6) Turn on the ultraviolet light to solidify the gel solution for 10-120 minutes to obtain an asymmetric wet adhesion hydrogel.
7. The Janus asymmetric wet adhesion hydrogel prepared by the method for preparing Janus asymmetric wet adhesion hydrogel based on an electrostatic field according to any one of claims 1-6.
8. The use of the Janus asymmetric wet adhesion hydrogel of claim 7 in the preparation of materials for postoperative anti-adhesion, smart sensors, and flexible electronic devices.