CN116688247B

CN116688247B - Janus zwitterionic hydrogel anti-adhesion film and preparation method and application thereof

Info

Publication number: CN116688247B
Application number: CN202310629643.1A
Authority: CN
Inventors: 李双阳; 董岸杰; 刘凌远; 张轶群; 荣辉
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2023-05-31
Filing date: 2023-05-31
Publication date: 2025-05-30
Anticipated expiration: 2043-05-31
Also published as: CN116688247A

Abstract

The invention discloses a Janus zwitterionic hydrogel anti-adhesion membrane and a preparation method and application thereof, and is characterized by comprising an adhesion layer and an anti-adhesion layer, wherein the adhesion layer is a copolymer of a zwitterionic monomer, N-acryloylglycinamide, 3-methacryloylglycinamide and a chemical cross-linking agent, and the anti-adhesion layer is a copolymer of a zwitterionic monomer, N-acryloylglycinamide and a chemical cross-linking agent. The adhesion layer of the Janus zwitterionic hydrogel anti-adhesion film has strong adhesion to wet tissues, can rapidly close wounds of different organs and rapidly stop bleeding, has good anti-adhesion performance, and can prevent adhesion of organs and tissues. The Janus zwitterionic hydrogel anti-adhesion membrane can be used for preventing adhesion of abdominal hernia, postoperative abdominal cavity, thoracic cavity and the like.

Description

Janus zwitterionic hydrogel anti-adhesion film and preparation method and application thereof

Technical Field

The invention relates to a Janus zwitterionic hydrogel anti-adhesion membrane and a preparation method and application thereof. The double-layer film is a double-layer film formed by combining an adhesion layer and an anti-adhesion layer formed by different zwitterionic copolymers, and is suitable for developing anti-adhesion patches.

Background

Surgery is an important method of treating various diseases. In surgery, tissue and organs are often inevitably damaged, leaving wounds that need to heal after surgery, relying on the self-healing function of the tissue. However, during normal healing, tissue and organs in the body are subject to contact with the wound at the surgical site, which can lead to post-operative tissue adhesions. Severe post-operative adhesions can lead to chronic pain and various complications such as adjacent organ dysfunction, ileus, female infertility, etc., severely affecting the quality of life of the patient, placing a heavy burden on the patient and possibly even threatening the patient's life. Accordingly, efforts have been made to develop various anti-adhesion strategies for isolating wounds created during surgery from tissue and organs or for attenuating tissue and organ inflammatory responses in an attempt to prevent post-operative adhesions.

The anti-adhesion membrane is a common and mature method for clinically preventing postoperative adhesion, and can directly and physically isolate an injured part from adjacent tissues and organs, thereby playing an anti-adhesion role. The ideal anti-adhesion membrane has good biodegradability, biocompatibility and proper tissue adhesiveness (without suture fixation), can keep a more complete physical form in the key period of anti-adhesion formation, does not influence the healing of wounds, or can promote the healing of wounds. In recent years, the application of the anti-adhesion film in surgical operations is more and more extensive, and the anti-adhesion film can effectively prevent the occurrence of postoperative tissue adhesion. The current commercial anti-adhesion membrane materials are usually polylactic acid (PLA), polyethylene glycol (PEG), carboxymethyl cellulose, hyaluronic acid and the like, which have poor adhesion performance with tissues, need surgical suturing and have great secondary damage to the tissues, and the general anti-adhesion membrane cannot avoid adhesion proliferation of cell tissues on the surface of the membrane, so that the anti-adhesion effect is affected.

Therefore, enhancing the adhesion properties to the tissue to be healed while also having an anti-bioadhesive effect to other tissues is an important direction for optimizing the properties of the anti-adhesion film.

Disclosure of Invention

The invention aims to design and prepare a Janus zwitterionic hydrogel anti-adhesion membrane, which is characterized by a double-layer membrane consisting of an adhesion layer with wet tissue adhesion and an anti-adhesion layer with anti-biological adhesion, can rapidly close wounds of different organs and has a hemostatic function, and the anti-adhesion layer has good anti-biological adhesion performance and is used for postoperative anti-adhesion treatment of abdominal hernia, abdominal cavity, thoracic cavity and the like.

In order to achieve the above purpose, the invention adopts the following technical scheme:

A Janus zwitterionic hydrogel anti-blocking film, which consists of an adhesion layer and an anti-blocking layer;

The adhesive layer is a copolymer of a zwitterionic monomer, N-acryloylglycine amide (NAGA), 3-methacryloyl Dopamine (DMA) and a chemical crosslinking agent, wherein the N-acryloylglycine amide can improve the gel strength of the adhesive layer, catechol groups in the 3-methacryloyl dopamine can be combined with various nucleophilic groups (such as amino groups, mercapto groups and imidazole groups) in polypeptides and proteins on the surface of a tissue so as to adhere to the surface of the tissue, the zwitterionic hydrogel has excellent hydrophilicity, can quickly absorb water molecules on the surface of the tissue so as to enhance the adhesion between the 3-methacryloyl dopamine and the surface of the tissue, and the chemical crosslinking agent can prevent the adhesive layer from swelling.

The anti-blocking layer is a copolymer of a zwitterionic monomer, N-acryloylglycinamide and a chemical cross-linking agent. The zwitterionic hydrogel formed by polymerizing the zwitterionic monomer has good hydrophilicity, and a stable hydration layer can be formed on the surface of the zwitterionic hydrogel, so that the occurrence of postoperative tissue adhesion can be effectively prevented, the strength of the hydrogel can be improved by the N-acryloylglycine amide, and swelling of the anti-adhesion layer can be prevented by the chemical crosslinking agent.

The adhesion layer of the Janus zwitterionic hydrogel anti-adhesion film has strong adhesion to wet tissues, can rapidly close wounds of different organs and rapidly stop bleeding, has good anti-adhesion performance, can inhibit surface adhesion of biological components such as proteins, cells and the like, and can prevent adhesion of organs and tissues.

Preferably, the adhesion layer is a copolymer formed by a zwitterionic monomer, N-acryloylglycinamide, 3-methacryloylglycine and a chemical crosslinking agent under the initiation of an initiator, and the anti-adhesion layer is a copolymer formed by a zwitterionic monomer, N-acryloylglycinamide and a chemical crosslinking agent under the initiation of an initiator.

Preferably, the ratio of the total mass of N-acryloylglycine amide monomer to the total mass of zwitterionic monomer in the copolymer for forming the adhesion layer is 0.125-2, the ratio of the total mass of 3-methacryloyl dopamine monomer to the total mass of zwitterionic monomer is 0.125-2, and the chemical cross-linking agent accounts for 0.5-15 w% of the total mass of zwitterionic monomer;

the ratio of the total mass of N-acryloylglycine amide monomer to the total mass of the zwitterionic monomer in the copolymer for forming the anti-adhesion layer is 0.125-0.75, and the chemical cross-linking agent accounts for 0.5-15 w% of the zwitterionic monomer.

Preferably, the zwitterionic monomer is selected from any one of methacryloyl ethyl Sulfobetaine (SBMA), 2-methacryloyl oxyethyl phosphorylcholine (MPC) and carboxylic acid betaine methacrylate (CBMA).

Preferably, the chemical cross-linking agent is selected from one or more of N, N-Methylenebisacrylamide (MBA), N, N-bis (acryloyl) cystamine (MSBA), ethylene glycol dimethacrylate (EBA), and bis (methacryloylethyl) carboxylic acid betaine (CBBA) poly (ethylene glycol) diacrylate (PEGDA).

Preferably, the initiator is selected from the group consisting of photoinitiators 2959.

The invention also discloses a preparation method of the Janus zwitterionic hydrogel anti-adhesion film, which comprises the following steps:

(1) Preparing an adhesion layer precursor solution, wherein the adhesion layer precursor solution is a mixed aqueous solution of a zwitterionic monomer, N-acryloylglycine amide, 3-methacryloyl dopamine, an initiator and a chemical crosslinking agent.

(2) Preparing an anti-adhesion layer precursor solution, wherein the anti-adhesion layer precursor solution is a mixed solution of a zwitterionic monomer, N-acryloylglycinamide, an initiator and a cross-linking agent.

(3) Injecting the precursor solution of the adhesion layer into a mold, polymerizing by an ultraviolet lamp at 10-60 ℃, injecting the precursor solution of the anti-adhesion layer into the mold after molding, and polymerizing by the ultraviolet lamp at 10-60 ℃ to obtain the Janus zwitterionic hydrogel anti-adhesion film.

Preferably, the concentration of the zwitterionic monomer in the adhesion layer precursor solution is 10-40 w%, the concentration of the N-acryloylglycine amide monomer is 5-20 w%, the concentration of the 3-methacryloylglycine amide monomer is 5-20 w%, the amount of the chemical cross-linking agent is 0.5-15 w%, and the amount of the initiator is 0.5-20% of the mass of the zwitterionic monomer;

The concentration of the zwitterionic monomer in the anti-adhesion layer precursor solution is 10-40 w%, the concentration of the N-acryloylglycine amide monomer is 5-13 w%, the amount of the cross-linking agent is 0.5-15 w% of the mass percentage of the amphoteric ion, and the amount of the initiator is 0.5-20 w% of the mass percentage of the amphoteric ion.

Preferably, the polymerization is carried out by ultraviolet lamp polymerization under 365nm ultraviolet lamp for 30-60min.

The Janus zwitterionic hydrogel anti-adhesion membrane provided by the invention can be singly used as a medical anti-adhesion patch, and can also be compatible with bioactive substances such as medicines, active factors, polypeptides and the like, electrodes and the like to form an anti-adhesion product for anti-adhesion treatment of diseases such as abdominal hernia, postoperative abdominal adhesion, thoracic adhesion and the like.

The beneficial effects of the invention are as follows:

The Janus zwitterionic hydrogel anti-adhesion film disclosed by the invention is simple in preparation technology, mild in preparation condition, low in cost, good in biocompatibility and long-acting in wet tissue adhesion and anti-adhesion effect, the adhesion layer solves the problem of traumatic injury caused by the fact that an existing anti-adhesion film or hernia repair sheet needs to be sutured or pinned for fixation, and the anti-adhesion layer solves the problems of poor biocompatibility and postoperative organ adhesion of the existing anti-adhesion film or hernia repair sheet, and the anti-adhesion film has application prospects in operations such as hernia repair sheet, postoperative anti-adhesion film and the like.

Drawings

FIG. 1 is a cross-sectional and surface SEM image of a Janus zwitterionic hydrogel anti-blocking film prepared in example 1.

FIG. 2 180 peel strength between each layer of interface of Janus zwitterionic hydrogel anti-blocking film prepared in example 1.

FIG. 3 water contact angle of each layer of Janus zwitterionic hydrogel anti-blocking film prepared in example 1.

FIG. 4 interfacial toughness and shear strength of Janus zwitterionic hydrogel anti-blocking films prepared in example 1 with wet pigskin surfaces.

FIG. 5 shows adhesion diagrams and shear strengths of Janus zwitterionic hydrogel anti-blocking films prepared in example 1 with different wet tissues.

FIG. 6 is a graph showing the burst pressure resistance test of Janus zwitterionic hydrogel anti-blocking films prepared in example 1 on different tissue surfaces.

FIG. 7A is a graph showing a commercial anti-blocking film (Hongjian polylactic acid anti-blocking film), a commercial PP patch (Fu)Light-weight polypropylene flat sheets and pre-cut flat sheets, medical technology company, ltd. Of smooth transportation in beijing days), and protein, platelet, bacteria and cell adhesion resistance graphs on the front and back sides of the Janus zwitterionic hydrogel anti-adhesion film prepared in example 1.

FIG. 8 is a schematic view of wound sealing of different organs in vitro of Janus zwitterionic hydrogel anti-adhesion film prepared in example 1.

FIG. 9 is a graph showing the hemostatic performance of the Janus zwitterionic hydrogel anti-adhesion membrane rabbit carotid artery prepared in example 1. (a) Janus zwitterionic hydrogel anti-adhesion membrane rabbit carotid artery hemostasis physical image, (b) Masson staining photographs at different time points after rabbit carotid artery hemostasis, and (c) carotid artery wound width at different time points after rabbit carotid artery hemostasis.

FIG. 10 shows the cytotoxicity test results of Janus zwitterionic hydrogel anti-blocking film of example 1.

FIG. 11A commercial anti-blocking film and Janus zwitterionic hydrogel anti-blocking film prepared in example 1 were used in the SD rat cecum-abdominal wall post-injury anti-blocking mode. (a) Commercial anti-adhesion film and Janus zwitterionic hydrogel anti-adhesion film prepared in example 1 were used for physical pictures at different time points after injury of the cecum-abdominal wall of SD rats, (b) commercial anti-adhesion film and Janus zwitterionic hydrogel anti-adhesion film prepared in example 1 were used for HE and Masson staining pictures after injury of the cecum-abdominal wall of SD rats.

FIG. 12A model of a commercial PP patch and Janus zwitterionic hydrogel anti-adhesion film of example 1 repairing a rabbit abdominal wall defect. (a) Commercial PP patches and Janus zwitterionic hydrogel anti-blocking films of example 1 were used to repair physical images at different time points after rabbit abdominal wall defects, (b) commercial PP patches and Janus zwitterionic hydrogel anti-blocking films of example 1 were used to repair HE and Masson stained photographs after rabbit abdominal wall defects.

In fig. 1-7 and 10, the front side is an adhesive layer, and the back side is an anti-blocking layer.

Detailed Description

The following description of the technical solutions in the embodiments of the present invention will be clear and complete, and it is obvious that the described embodiments are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Example 1

(1) Preparation of an adhesive layer hydrogel precursor solution 2mL distilled water was added with 0.4g SBMA (14 w% concentration), 0.2g NAGA (7 w% concentration), 0.2g DMA (7 w% concentration), 0.02g MBA (5 w% of SBMA) and 0.008g photoinitiator I-2959 (2 w% of SBMA).

(2) Preparation of the anti-blocking layer hydrogel precursor solution 2mL distilled water was taken, and 0.4g SBMA (15.2 w% concentration), 0.2g NAGA (7.6 w% concentration), 0.02g MBA (5 w% of SBMA) and 0.008g photoinitiator I-2959 (2 w% of SBMA) were added.

(3) The preparation method of the Janus zwitterionic hydrogel anti-adhesion film comprises the steps of injecting an adhesion layer precursor solution into a groove of a silica gel mold with the thickness of 2cm multiplied by 2mm, polymerizing for 30min at 25 ℃ under a 365nm ultraviolet lamp, injecting the anti-adhesion layer precursor solution into the mold after molding, and polymerizing for 30min at 25 ℃ under the 365nm ultraviolet lamp to obtain the Janus zwitterionic hydrogel anti-adhesion film.

The structural properties of the antiblocking films prepared in example 1 are shown in FIGS. 1-12 and Table 2.

FIG. 1 is a cross-sectional and surface SEM image of a Janus zwitterionic hydrogel anti-blocking film prepared in example 1, and it can be seen from FIG. 1 that the Janus zwitterionic hydrogel anti-blocking film has a double-layer structure and the bonding between the two layers is firm. As can be seen from FIG. 2, janus zwitterionic hydrogel anti-blocking film double layers have stronger binding force. As can be seen from the water contact angle of each layer of the anti-blocking film in FIG. 3, the difference of hydrophilicity between each layer of the Janus zwitterionic hydrogel anti-blocking film is obvious, and the reverse anti-blocking layer has super hydrophilicity. Fig. 4 shows that the front adhesive layer of the Janus zwitterionic hydrogel anti-blocking film has strong adhesion on the pigskin surface. Fig. 5 illustrates that the Janus zwitterionic hydrogel anti-blocking film has good wet tissue adhesion properties at different tissue surfaces. The data in fig. 6 shows that the Janus zwitterionic hydrogel anti-adhesion membrane-enclosed wet tissue has strong burst pressure resistance. FIG. 7 shows the results of the anti-blocking film (Hongjian polylactic acid anti-blocking film) and the commercial PP patch (Fu)Light-weight polypropylene flat sheet and pre-cut flat sheet, beijing Tian-facilitated medical technology Co., ltd.), the anti-blocking layer of the Janus zwitterionic hydrogel anti-blocking film prepared in example 1 has better anti-bioadhesion properties than the above-mentioned products.

The Janus zwitterionic hydrogel anti-adhesion membrane prepared in example 1 is used for sealing wounds of different organs in vitro, as shown in fig. 8, the Janus zwitterionic hydrogel anti-adhesion membrane can rapidly seal wounds of different organs, and the sealed wounds of the organs have good sealing performance.

As shown in figure 9, the hemostatic performance test of the Janus zwitterionic hydrogel anti-adhesion membrane rabbit carotid artery prepared in the embodiment 1 shows that the Janus zwitterionic hydrogel anti-adhesion membrane can rapidly seal rabbit carotid artery and has rapid hemostatic function. The cytotoxicity test result of FIG. 10 shows that the Janus zwitterionic hydrogel anti-adhesion membrane has good cell compatibility.

As shown in fig. 11, the performance of the Janus zwitterionic hydrogel anti-adhesion film prepared in example 1 was evaluated on the SD rat cecum-abdominal wall injury adhesion model using a commercial anti-adhesion film as a control. It can be seen from fig. 11 that animals using the Janus zwitterionic hydrogel anti-blocking film did not develop visceral adhesions. The results of the test for repairing rabbit abdominal wall defects, as shown in FIG. 12, demonstrate that the hernia is substantially repaired after 28 days in animals using Janus zwitterionic hydrogel anti-adhesion films, and no organ adhesion occurs.

Examples 2 to 5

The Janus zwitterionic hydrogel anti-blocking film was prepared by following the procedure of example 1, operating the same as example 1, reaction temperature and reaction time, and adjusting the amounts of each reactant according to the composition of Table 1.

Examples 6 to 8

The procedure of example 1 was followed, using different zwitterionic monomers and different chemical cross-linking agents, to adjust the amounts of each reactant, to prepare precursor solutions for the adhesion layer and the antiblocking layer, respectively, according to the compositions of Table 1.

The preparation method of the Janus zwitterionic hydrogel anti-adhesion film comprises the steps of injecting an adhesion layer precursor solution into a groove of a silica gel mold with the thickness of 2cm multiplied by 2mm, polymerizing for 40min at 40 ℃ under a 365nm ultraviolet lamp, injecting the anti-adhesion layer precursor solution into the mold after molding, and polymerizing for 40min at 40 ℃ under the 365nm ultraviolet lamp to obtain the Janus zwitterionic hydrogel anti-adhesion film.

Examples 9 to 13

The procedure of example 1 was followed, using different zwitterionic monomers and different cross-linking agents, to adjust the amounts of the reactants, to prepare precursor solutions for the adhesion layer and the antiblocking layer, respectively, according to the composition of Table 1.

The preparation method of the Janus zwitterionic hydrogel anti-adhesion film comprises the steps of injecting an adhesion layer precursor solution into a groove of a silica gel mold with the thickness of 2cm multiplied by 2mm, polymerizing for 50min at 30 ℃ under a 365nm ultraviolet lamp, injecting the anti-adhesion layer precursor solution into the mold after molding, and polymerizing for 50min at 30 ℃ under the 365nm ultraviolet lamp to obtain the Janus zwitterionic hydrogel anti-adhesion film.

Example 14

The preparation method of the Janus zwitterionic hydrogel anti-adhesion film comprises the steps of injecting an adhesion layer precursor solution into a groove of a 2cm multiplied by 2mm silica gel mold, polymerizing for 60min at 10 ℃ under a 365nm ultraviolet lamp, injecting the anti-adhesion layer precursor solution into the mold after molding, and polymerizing for 60min at 10 ℃ under the 365nm ultraviolet lamp to obtain the Janus zwitterionic hydrogel anti-adhesion film.

Example 15

The preparation method of the Janus zwitterionic hydrogel anti-adhesion film comprises the steps of injecting an adhesion layer precursor solution into a groove of a 2cm multiplied by 2mm silica gel mold, polymerizing for 45min at 60 ℃ under a 365nm ultraviolet lamp, injecting the anti-adhesion layer precursor solution into the mold after molding, and polymerizing for 45min at 60 ℃ under the 365nm ultraviolet lamp to obtain the Janus zwitterionic hydrogel anti-adhesion film.

The performances of the anti-blocking layer and the adhesion layer of the Janus zwitterionic hydrogel anti-blocking film prepared in examples 1-15 are shown in tables 2 and 3.

TABLE 1 examples 1-15 precursor solution compositions for preparing Janus zwitterionic hydrogel anti-blocking films

^a Refers to the concentration of monomer in the precursor solution, ^b refers to the percentage of crosslinker or initiator to zwitterionic monomer mass;

Zm is a zwitterionic monomer, cm is a cross-linking agent;

Table 2 anti-adhesion properties of anti-adhesion layer of Janus zwitterionic hydrogel anti-adhesion films prepared in examples 1-15

MPC 2-methacryloyloxyethyl phosphorylcholine, CBMA carboxylic betaine methacrylate, ad _pro protein adhesion, ad _pla platelet adhesion, ad _bac bacterial adhesion, ad _cel cell adhesion.

As can be seen from the data in table 2, the swelling ratio of the anti-blocking layer formed by the other two zwitterionic monomers (MPC, CBMA) is almost unchanged compared to the zwitterionic monomer SBMA and also shows very excellent super-hydrophilic, protein-binding, platelet-binding, bacterial-binding and cell-binding properties thanks to the higher hydrophilicity of the zwitterionic polymer and extremely low interactions with proteins, platelets, bacteria, cells, etc. The hydrophilic and anti-bioadhesive properties of the anti-adhesion layer are improved with increasing SBMA monomer concentration, but the swelling rate is also improved, while the swelling rate of the anti-adhesion layer is reduced with increasing NAGA monomer concentration, but the hydrophilic and anti-bioadhesive properties are reduced. The anti-swelling performance of the anti-adhesion layer is improved along with the improvement of the concentration of the cross-linking agent MBA, but the hydrophilicity and the anti-bioadhesion performance of the anti-adhesion layer are reduced, and the hydrophilicity and the anti-bioadhesion performance of the anti-adhesion layer are almost unchanged along with the change of the dosage of the photoinitiator I-2959. This is because as the content of the crosslinking agent increases, the polymer segments become more entangled with each other, their water absorption decreases, their surface hydration ability decreases, and thus their swelling ratio decreases, and their bioadhesive resistance decreases. The overall properties of the hydrogel are almost independent of the initiator content.

The adhesive layer adhesion time, adhesive strength, burst pressure, hemostatic time and swelling ratio of the Janus zwitterionic hydrogel anti-adhesive films prepared by different types of reactants and different amounts of reactants were measured and shown in table 3.

TABLE 3 adhesive layer Properties of Janus zwitterionic hydrogel anti-blocking films prepared in examples 1-15

As can be seen from the data in Table 3, the swelling ratio of the adhesion layer formed by the other two zwitterionic monomers (MPC, CBMA), the adhesion time to the tissue, the adhesion strength and the hemostatic time were not significantly changed compared to the zwitterionic monomer SBMA. Compared with the cross-linking agent MBA, the adhesive time, the adhesive strength, the hemostatic time and the swelling rate of the adhesive layer formed by the other four cross-linking agents (MSBA, EBA, CBBA, PEGDA) and the tissue are not obviously changed. The adhesive performance of the front adhesive layer of the hydrogel anti-adhesive film is improved along with the improvement of the concentration of the DMA monomer, but the front adhesive performance of the hydrogel anti-adhesive film is not changed after the concentration of the DMA monomer is improved to a certain range, the swelling rate of the front adhesive layer of the hydrogel anti-adhesive film is reduced along with the improvement of the concentration of the NAGA monomer, but the adhesive performance of the hydrogel anti-adhesive film is reduced, the adhesive time and the hemostatic time are reduced along with the improvement of the concentration of the SBMA monomer, but the overall adhesive strength is reduced, and the swelling rate is improved. With the increase of the concentration of the cross-linking agent MBA, the anti-swelling performance of the adhesive layer is improved, the adhesive time and the hemostatic time are prolonged, the shear strength and the burst pressure are reduced, and with the change of the dosage of the photoinitiator I-2959, the adhesive performance of the adhesive layer is almost unchanged. This is because as the content of the crosslinking agent increases, the polymer segments are entangled with each other more tightly, the water absorption thereof decreases, the water absorption rate becomes slow, the time taken to absorb water molecules on the surface of the wet tissue increases, and thus the adhesion time and the hemostatic time increase, and the swelling rate decreases. Since the polymer segments are entangled tightly with each other, and are in direct contact with the tissue surface, the number of catechol groups having higher affinity is reduced, and thus, the adhesion property is lowered.

Comparative example 1

The procedure of example 1 was followed, except that the anti-blocking layer was free of zwitterionic monomer and the other monomer concentrations were maintained, as in example 1, with the reaction temperature and reaction time being the same as in example 1.

Comparative example 2

The procedure of example 1 was followed, except that the adhesive layer was free of DMA monomer and the other monomer concentrations were kept unchanged, as in example 1, with the reaction temperature and reaction time being the same as in example 1.

Table 4 adhesion resistance of adhesion preventing layer of Janus zwitterionic hydrogel adhesion preventing film prepared in comparative example 1

As can be seen from the data in table 4, when the anti-adhesion layer is free of the zwitterionic monomer, the swelling rate of the anti-adhesion layer is greatly reduced, but the surface hydrophilicity of the material is reduced, and the protein adhesion resistance, the platelet adhesion resistance, the bacterial adhesion resistance and the cell adhesion resistance are reduced, because the zwitterionic polymer has higher hydrophilicity, a hydration layer can be formed on the surface of the anti-adhesion layer, and the occurrence of bioadhesion is reduced.

TABLE 5 adhesive layer Properties of Janus zwitterionic hydrogel anti-blocking films prepared in comparative example 2

As can be seen from the data in table 5, when the adhesive layer is free of DMA monomers, the adhesive layer of the Janus zwitterionic hydrogel anti-adhesive film has no adhesive properties at the tissue surface, since catechol groups in DMA can bind to a variety of nucleophilic groups (such as amino, thiol, and imidazole groups) in polypeptides and proteins on the tissue surface, thereby adhering to the tissue surface.

The test methods of fig. 1-12 are as follows:

characterization method of Janus zwitterionic hydrogel anti-blocking film:

1. Morphology test of Janus zwitterionic hydrogel anti-adhesion film under a scanning electron microscope:

The surface and cross-sectional morphology of Janus zwitterionic hydrogel anti-blocking films were analyzed using a field emission scanning electron microscope (S-4800, HITACHI). The sample was immersed in PBS solution, subjected to ultrasonic cleaning, then subjected to freeze-drying, cut into 1X 1cm ², surface-sprayed with gold, and fixed on an observation platform with conductive adhesive. During observation, the acceleration voltage was set to 15eV.

180 ° Peel test of janus zwitterionic hydrogels:

The interfacial bond strength between the Janus patch bilayers was measured by a 180 ° peel test. Firstly, preparing Janus patches with the degree of 20mm, the length of 200 mm and the thickness of 2 mm, and respectively fixing an adhesion layer and an anti-adhesion layer on a pulling machine. Stretching at a strain rate of 5 mm/min, the pulling force during peeling was recorded. Peel strength is the ratio of the tensile force to the contact width between the bilayers. From the test results, the bonding strength between the hydrogel and the base material can be calculated in units of N/m.

Janus zwitterionic hydrogel anti-blocking film contact angle test:

The hydrophilicity of both sides of the Janus zwitterionic hydrogel anti-blocking film was characterized using a DSA100 (Kruss GmbH, germany) contact angle meter. A dry Janus zwitterionic hydrogel anti-blocking film was attached to a glass sheet and mounted on a goniometer. In the static contact angle measurement, a total of 3 μl of double distilled water was dropped on the air side surface of the sample at room temperature and relative humidity of 80%, and the water contact angle of the surface was measured. Five measurements were made for each group and averaged.

Adhesive performance test of janus zwitterionic hydrogel anti-blocking film:

the adhesive property test of the study is divided into two types, namely a lap shear test and a T-shaped peeling test, and the lap shear test and the T-shaped peeling test respectively represent the Shear Strength (SS) and the T-shaped peeling strength (TPS) of the Janus zwitterionic hydrogel anti-adhesion film.

For the lap shear test, one surface of the Janus zwitterionic hydrogel anti-blocking film and the wet tissue sample were each adhered to a rigid polyester backing with cyanoacrylate, and then 500g of pressure was applied to each of the two liners to attach the patch to the tissue sample for 10min. Then, the universal tensile machine is loaded in a lap shear test mode, the loading speed is set to be 5mm & min ^-1, and the test is carried out until the Janus zwitterionic hydrogel anti-adhesion film is pulled off from wet tissues. The Shear Strength (SS) of the Janus zwitterionic hydrogel anti-blocking film is calculated and defined as follows:

Wherein F _max represents the maximum pull-out force, and L and W represent the length and width, respectively, of the initial contact area of the Janus zwitterionic hydrogel anti-blocking film with the wet tissue sample.

For the T-peel test, two L-shaped backing materials were prepared in advance and a Janus zwitterionic hydrogel anti-blocking film and one side of the wet tissue were adhered to a rigid polyester backing with cyanoacrylate. Then, the Janus zwitterionic hydrogel anti-adhesion film and the exposed surface of the wet tissue are contacted with each other to form a T shape, 500g pressure is applied to attach the Janus zwitterionic hydrogel anti-adhesion film to the tissue for 10min, a universal tensile machine is loaded in a T-shaped peeling test mode, and the loading rate is set to be 5mm & min ^-1 for testing until the Janus zwitterionic hydrogel anti-adhesion film and the wet tissue are separated from each other. T-Type Peel Strength (TPS) of Janus zwitterionic hydrogel anti-blocking film is obtained through calculation, and the definition formula is as follows:

where F _max represents the maximum peel force and W represents the width of the initial contact area of the Janus zwitterionic hydrogel anti-blocking film with the wet tissue sample.

Burst pressure test of janus zwitterionic hydrogel anti-blocking films:

The prepared wet tissue sample was first cut into a round sheet shape, and a circular hole having a diameter of 8mm was opened at the center thereof. The wet tissue was then secured to the opening of an open-topped cylindrical stainless steel container, and one side of a round Janus zwitterionic hydrogel anti-blocking membrane 15mm in diameter was placed over the circular hole of the tissue sample and held for 10min with 500g force applied to adhere the two. Air was introduced into the container at a rate of 10 mL/min ^-1 to generate a stable increase in internal pressure, and the internal pressure at which the Janus zwitterionic hydrogel anti-blocking film separated from the wet tissue was recorded.

Anti-bioadhesion test of Janus zwitterionic hydrogel anti-adhesive film anti-adhesive layer:

Protein adhesion test the test method used in the protein adsorption test is BCA protein kit method. The test and characterization were performed by detecting the adhesion behavior of a mixed solution of three proteins, bovine serum albumin, fibrinogen and gamma-GL, on a sample. The samples were first cut to a size of 1X 1cm ², soaked in PBS solution at 37℃for 6 hours, then the cut samples were grouped, immersed in a mixed solution of proteins (2.0 mg.mL ^-1 bovine serum albumin solution, 0.3 mg.mL ^-1 fibrinogen solution, 1 mg.mL ^-1. Gamma. -GL protein solution) and soaked for 2 hours at 37 ℃. Subsequently, the sample was washed with a fresh PBS solution and transferred to a 96-well plate containing 1.0wt% Sodium Dodecyl Sulfate (SDS) solution, and sonicated at room temperature for 20min to isolate the adsorbed proteins. Finally, the absorbance at 562nm was measured with BCA protein assay kit to obtain protein concentration.

Platelet adhesion test by first separating whole blood with a high-speed centrifuge at a centrifugation speed of 1500r/min for 15min, and collecting the supernatant as Platelet Rich Plasma (PRP) for use. The prepared samples (1X 1cm ²) are sterilized and placed into 12-hole plates, 100 mu L of PRP is respectively sucked by a pipettor and evenly dripped onto the surfaces of the samples, and the samples are placed into a constant-temperature water bath box at 37 ℃ for shaking incubation for 1h. The sample is taken out, washed by PBS for 5 times, then immersed in 2.5wt% glutaraldehyde solution, fixed at 4 ℃ overnight, taken out of glutaraldehyde solution, respectively prepared into absolute ethanol solutions with the concentration of 50%, 75%, 90% and 100%, and dried sample is respectively soaked into the gradient absolute ethanol solution for dehydration, wherein the dehydration time is 15min each time. And observing the number of the platelets adhered to the surface of the sample by adopting a scanning electron microscope.

Cell adhesion test the samples were cut to a size of 5X 5mm ² and sterilized by UV irradiation at room temperature for 4h. Then, a cell suspension (5X 10 ⁵ cells/mL, 1 mL/well) of mouse embryonic fibroblasts (3T 3-L1) was incubated with the sample at 37℃for 12h. The non-adherent cells were isolated with PBS, and the adherent cells were fixed with paraformaldehyde and then soaked with Triton X-100 for 5min. Then, actin cytoskeleton and nuclei were visualized by staining with phalloidin and DAPI, respectively. And observing the adhesion condition of cells on the surface of the sample by using a laser scanning confocal microscope, and determining the cell adhesion resistance of the sample.

Bacterial adhesion test staphylococcus aureus and escherichia coli were selected to evaluate the antibacterial adhesion ability of the samples. The samples were cut to a size of 5X 5mm ², sterilized and then immersed in sterile PBS buffer at room temperature for 6h. Subsequently, the samples were transferred to 24-well plates, each soaked with a single bacterial suspension (1 mL, 1.0X10 ⁸CFU·mL^-1) for 6h, and rinsed three times with sterile PBS to remove weakly or non-adherent bacteria from the samples. The samples were fixed in 4% glutaraldehyde solution for 12h and then dehydrated with a series of increasing concentrations of ethanol (50%, 60%, 70%, 80%, 90% and 100%, 30min each). For the E.coli group, the cells were observed by SEM, and for the Staphylococcus aureus group, the cells were stained with DAPI and then observed by fluorescence microscopy.

In vitro organ adhesion and sealing capability test of Janus zwitterionic hydrogel anti-adhesion membrane:

And evaluating the adhesion performance of the Janus zwitterionic hydrogel anti-adhesion film to different organs through an in-vitro organ adhesion experiment. And taking tissue specimens of heart, lung, muscle, kidney, trachea, aorta and the like of the pig for adhesion test. For the adhesion test of the isolated pig heart, a wound with the length of 1cm is cut by a scalpel, and pig blood is sprayed to simulate the condition of tissue injury. Then a Janus zwitterionic hydrogel anti-blocking film was adhered to the wound site and pressed for 15 seconds to seal the wound. After 8 hours, the adhesion was checked and the Janus zwitterionic hydrogel anti-blocking film was torn off. To further test the sealing effect of the Janus zwitterionic hydrogel anti-adhesion film on the small intestine after injury, two 5mm long incisions were made on the surface of the small intestine with a scalpel, and then one of the incisions was closed with the Janus zwitterionic hydrogel anti-adhesion film. After the isolated small intestine is placed under water for 12 hours, one side of the isolated small intestine is blocked, air is filled from the other side, the bubble generation condition at the wound is observed under water, and the air tightness of the incision sealed by the Janus zwitterionic hydrogel anti-adhesion membrane is checked. To further test the sealing effect of the Janus zwitterionic hydrogel anti-adhesion film on the post-injury trachea and lung lobes, 5mm long incisions were cut on the trachea and lung lobes of the pigs respectively with a scalpel, air was inflated from the tracheae to inflate the pig lungs, the incision was observed under water, then the incision was closed with the Janus zwitterionic hydrogel anti-adhesion film, and the incision was observed again after the closing to determine the sealing effect.

Janus zwitterionic hydrogel anti-adhesion membrane rabbit internal carotid artery hemostatic capability test:

Weighing New Zealand white rabbits for experiments, sequentially weighing and recording the body weight, selecting 20mg/kg ketamine and 3mg/kg tolylthiazide to carry out anesthesia, fixing the ketamine and the tolylthiazide on an operating table after anesthesia, continuously carrying out anesthesia by using a respiratory anesthesia machine, exposing carotid artery after skin preparation sterilization, clamping both ends by using a hemostatic clamp, establishing a carotid artery injury model by using a needle with the diameter of 2mm, loosening the hemostatic clamp to confirm blood outflow, closing the hemostatic clamp, sealing the injury part by using Janus zwitterionic hydrogel anti-adhesion membrane, opening the hemostatic clamp after 15 seconds of pressing, and observing whether the Janus zwitterionic hydrogel anti-adhesion membrane seals the injury part or not, and whether blood flows out. On days 3, 5 and 7 after the experiment, the rabbits were euthanized by injecting excessive sodium pentobarbital, and the carotid was taken out, wound adhesion was observed, HE and mahalanobis staining was performed, and wound repair was observed.

In vitro cytotoxicity test of janus zwitterionic hydrogel anti-blocking films:

After the sample (2X 2mm ²) was sterilized by ultraviolet irradiation at room temperature for 4 hours, it was placed in a 96-well plate, and the cells were diluted to a concentration of 1X 10 ⁵ cells/mL. 100 μl of each well of the 96-well plate was added, and after 24 hours, proliferation rate of the cells was measured by Cell Counting Kit-8 (CCK 8) method.

Rat in vivo cecum-abdominal wall adhesion model test of janus zwitterionic hydrogel anti-adhesion membrane:

15 healthy rats were selected for the experiment, and the control group (without any anti-adhesion treatment) was the commercial anti-adhesion membrane treatment group and the Janus zwitterionic hydrogel anti-adhesion membrane treatment group, respectively. The whole experiment was carried out under aseptic conditions. Rats were anesthetized with 10% chloral hydrate, placed in the supine position, then the abdomen was shaved and disinfected with 0.5% iodine. The abdomen was carefully opened with a scalpel, a wound of about 3cm in length was formed, and the organs in the abdomen were exposed. The serosa on the cecum surface was carefully rubbed with a medical sandpaper until slight damage and bleeding occurred on the serosa surface, but no perforation had occurred. The peritoneum was then gently scraped with a medical sandpaper to expose the muscular layer of the right abdominal wall. For the control group, the abdominal wall and cecum wounds were slightly sutured so that the two wounds were in contact. For the CF group, the polylactic acid film is put between the abdominal wall wound surface and the cecum wound surface, and the three are sutured. And directly attaching the adhesive surface of the Janus zwitterionic hydrogel anti-adhesion film to the abdominal wall of the wound surface to completely cover the wound surface. Each rat was opened at day 14 and day 28 after the experiment, and wound adhesion was observed and photographed. All experimental rats were euthanized on day 28 by injection of excess sodium pentobarbital.

Rabbit abdominal wall hernia repair model test of janus zwitterionic hydrogel anti-adhesion membrane:

The new zealand white rabbits for experiments are taken, the weights are weighed and recorded in sequence, 20mg/kg of ketamine and 3mg/kg of xylazine are selected for anesthesia, the supine position is taken after anesthesia, and the skin is sterilized by 0.5% iodophor after dehairing and skin preparation. The abdominal wall hernia model was prepared by cutting the skin and subcutaneous tissue layer by layer at the length of the lower abdominal median incision, exposing the rectus abdominis on both sides, cutting two intact muscle defects (remaining peritoneum) from the flat abdominal muscle, and 1cm in diameter, and implanting the pre-prepared commercial PP patch and the Janus zwitterionic hydrogel anti-adhesion membrane of example 1 into the abdominal cavity, wherein the commercial PP patch was fixed in sequence along the edges, and the Janus zwitterionic hydrogel anti-adhesion membrane was fixed by its own adhesive properties, and then closing the abdomen layer by layer using sutures. On days 14 and 28 post-surgery, 6 experimental rabbits were taken at each time point, were observed for adhesion and healing and were photographed after abdominal skin preparation, and were then stored in formalin solution for use.

In the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A Janus zwitterionic hydrogel anti-adhesion membrane, characterized in that the anti-adhesion membrane consists of an adhesion layer and an anti-adhesion layer;

The adhesive layer is a copolymer of zwitterionic monomers, N-acryloylglycine amide, 3-methacryloyldopamine and a chemical cross-linking agent;

The anti-adhesion layer is a copolymer of zwitterionic monomers, N-acryloylglycine amide and a chemical cross-linking agent.

2. A Janus zwitterionic hydrogel anti-adhesion film according to claim 1, characterized in that the adhesion layer is a copolymer formed by zwitterionic monomers, N-acryloylglycine amide, 3-methacryloyldopamine and a chemical crosslinking agent under the initiation of an initiator; and the anti-adhesion layer is a copolymer formed by zwitterionic monomers, N-acryloylglycine amide and a chemical crosslinking agent under the initiation of an initiator.

3. A Janus zwitterionic hydrogel anti-adhesion film according to claim 1, characterized in that the ratio of the total mass of N-acryloylglycine amide monomers to the total mass of zwitterionic monomers in the copolymer forming the adhesion layer is 0.125-2, the ratio of the total mass of 3-methacryloyldopamine monomers to the total mass of zwitterionic monomers is 0.125-2, and the percentage of chemical crosslinking agents to the total mass of zwitterionic monomers is 0.5 w%-15 w%;

The ratio of the total mass of N-acryloylglycine amide monomers to the total mass of zwitterionic monomers in the copolymer forming the anti-adhesion layer is 0.125-0.75, and the mass percentage of the chemical crosslinking agent to the zwitterionic monomers is 0.5 w%-15 w%.

4. The Janus zwitterionic hydrogel anti-adhesion film according to claim 1, characterized in that the zwitterionic monomer is selected from any one of methacryloylethyl sulfobetaine, 2-methacryloyloxyethyl phosphorylcholine, and carboxylic acid betaine methacrylate.

5. A Janus zwitterionic hydrogel anti-adhesion film according to claim 1, characterized in that the chemical crosslinking agent is selected from one or more of N,N-methylenebisacrylamide, N,N-bis(acryloyl)cystamine, ethylene glycol dimethacrylate, dimethacryloylethylcarboxylic acid betaine, and poly(ethylene glycol) diacrylate.

6 . The Janus zwitterionic hydrogel anti-adhesion film according to claim 2 , wherein the initiator is selected from photoinitiator 2959.

7. A method for preparing a Janus zwitterionic hydrogel anti-adhesion film according to any one of claims 1 to 6, characterized in that it comprises the following steps:

(1) preparing an adhesion layer precursor solution, wherein the adhesion layer precursor solution is a mixed aqueous solution of zwitterionic monomer, N-acryloylglycine amide, 3-methacryloyldopamine, an initiator and a chemical crosslinking agent;

(2) preparing an anti-adhesion layer precursor solution, wherein the anti-adhesion layer precursor solution is a mixture of zwitterionic monomer, N-acryloylglycine amide, an initiator and a cross-linking agent;

(3) Injecting the adhesion layer precursor solution into the mold, polymerizing it with an ultraviolet lamp at 10-60°C, and after molding, injecting the anti-adhesion layer precursor solution into the mold again, polymerizing it with an ultraviolet lamp at 10-60°C, to obtain the Janus zwitterionic hydrogel anti-adhesion film.

8. The method for preparing a Janus zwitterionic hydrogel anti-adhesion film according to claim 7, characterized in that the concentration of zwitterionic monomers in the adhesion layer precursor solution is 10 w%-40 w%, the concentration of N-acryloylglycine amide monomers is 5 w%-20 w%, the concentration of 3-methacryloyldopamine monomers is 5 w%-20 w%, the amount of chemical crosslinking agent accounts for 0.5 w%-15 w% of the mass percentage of zwitterionic monomers, and the amount of initiator accounts for 0.5 w%-20 w% of the mass percentage of zwitterionic monomers;

The concentration of zwitterionic monomers in the anti-adhesion layer precursor solution is 10 w%-40 w%, the concentration of N-acryloylglycine amide monomers is 5 w%-13 w%, the amount of crosslinking agent accounts for 0.5 w%-15 w% of the mass percentage of zwitterions, and the amount of initiator accounts for 0.5 w%-20 w% of the mass percentage of zwitterions.

9. Use of a Janus zwitterionic hydrogel anti-adhesion film according to any one of claims 1 to 6 in the preparation of a medical anti-adhesion patch.

10. Use of a Janus zwitterionic hydrogel anti-adhesion membrane according to claim 9 in the preparation of a medical anti-adhesion patch, characterized in that the Janus zwitterionic hydrogel anti-adhesion membrane is used alone or in combination with any one or more of drugs, active factors, polypeptide bioactive substances and electrodes to prepare a medical anti-adhesion patch.