Preparation method and application of quaternary ammonium salt modified bacterial cellulose hydrogel

Abstract

The invention provides a preparation method of quaternary ammonium salt modified bacterial cellulose hydrogel and application of the quaternary ammonium salt modified bacterial cellulose hydrogel. Comprising the following steps: activation of a strain, preparation of a seed solution, preparation of bacterial cellulose hydrogel BC, preparation of bacterial cellulose hydrogel bromide BC-Br, preparation of a quaternary ammonium salt monomer VPIM-Br, and preparation of quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM. The problems that an existing bacterial cellulose hydrogel wound dressing is complex in preparation process, poor in biocompatibility, capable of generating toxicity to human cells or tissue organs, not ideal in antibacterial effect and the like are solved.

Description

Technical Field

[0001] The invention relates to the technical field of antibacterial materials, and in particular to a preparation method and application of a quaternary ammonium salt-modified bacterial cellulose hydrogel. Background Art

[0002] The skin can effectively isolate the human body from the external environment and resist a large number of external bacteria from invading the human body. When the skin is damaged, wound dressings are a material that can temporarily replace the damaged skin to act as a barrier. They prevent infection, absorb wound secretions, keep the wound moist, and promote healing during the wound healing process. Traditional wound dressings mainly include cotton, gauze, linen, and bandages. These wound dressings are cheap and widely available. However, these traditional wound dressings still have some problems in use: they absorb less tissue fluid, are easily soaked by tissue fluid, and need to be replaced frequently; they are easy to adhere to wound mucus, causing secondary skin damage. With the development of modern medicine, hydrogel wound dressings are a highly hydrophilic three-dimensional network polymer with good biocompatibility, swelling, and mechanical properties similar to the extracellular matrix of soft tissue. Hydrogels can provide a long-term and stable moist environment during wound repair, which helps cell migration and regeneration and promotes healing.

[0003] Bacterial cellulose is a natural hydrogel, mainly produced by xylose Gluconacetobacter. It has a natural ultrafine fiber three-dimensional nano-network structure, highly porous, high tensile strength and elastic modulus; high hydrophilicity, good air permeability, water absorption, water permeability, extraordinary water retention and high wet strength. In addition, a large number of studies have shown that bacterial cellulose has good in vivo and in vitro biocompatibility and biodegradability, which makes bacterial cellulose itself applicable to biomedical fields, such as wound dressings, tissue engineering scaffolds and drug release.

[0004] At present, the preparation method of bacterial cellulose hydrogel wound dressings mainly uses bacterial cellulose as the matrix material and enhances its performance by adding reinforcing materials. Bacterial cellulose is often compounded with other materials with antibacterial and anti-inflammatory functions to prepare bacterial cellulose composite hydrogel wound dressings to improve their mechanical properties, antibacterial properties, and wound healing abilities. However, bacterial cellulose hydrogel wound dressings still have the following problems: the preparation process is complex and the biocompatibility is poor. At the same time, the antibacterial, anti-inflammatory and wound healing substances in bacterial cellulose hydrogel wound dressings are toxic to human cells or tissues and organs, and the antibacterial effect is not ideal. Summary of the invention

[0005] Based on this, the present invention provides a preparation method and application of quaternary ammonium salt modified bacterial cellulose hydrogel, which solves the problems of existing bacterial cellulose hydrogel wound dressings, such as complex preparation process, poor biocompatibility, toxicity to human cells or tissues and organs, and unsatisfactory antibacterial effect.

[0006] In order to solve the above technical problems, one of the objects of the present invention is to provide a method for preparing a quaternary ammonium salt modified bacterial cellulose hydrogel, comprising the following steps: S1. Activation of bacterial strains: inoculate xylose Gluconacetobacter into an agar medium, place it in a constant temperature box, and culture it at 30° C. for 24-72 hours to obtain activated bacterial strains; S2, preparation of seed solution: take the activated bacteria obtained in S1 and inoculate it into a conical flask filled with liquid culture medium, place it in a bacterial culture shaker, and culture it at 30°C and 150 r / min for 48-72h to obtain seed solution; S3, preparation of bacterial cellulose hydrogel BC: inoculate the seed solution obtained in S2 into the fermentation medium, place it in a constant temperature box, and culture it at 30°C for 7 days to obtain bacterial cellulose, soak and wash it with deionized water, boil it in 0.1 mol / L sodium hydroxide solution, and wash it with deionized water until the pH value is 6.98-7.02 to obtain bacterial cellulose hydrogel BC; S4. Preparation of bacterial cellulose hydrogel bromide BC-Br: Add bacterial cellulose hydrogel BC to dimethylformamide and triethylamine solution, introduce nitrogen, add 2-bromoisobutyl bromide under magnetic stirring in an ice-water bath, react at 0°C for 3 h, stir at 25°C for 24 h, wash with a mixed solution of ethanol and deionized water to obtain bacterial cellulose hydrogel bromide BC-Br; S5. Preparation of quaternary ammonium salt monomer VPIM-Br: 1-vinyl imidazole and 1-bromopentane were added to cyclohexane, reacted at 50°C for 24 h, cooled to room temperature, stored in a -20°C refrigerator for 12-24 h, added with tetrahydrofuran, magnetically stirred until a white solid precipitated, the supernatant was discarded, and vacuum dried at 30-40°C for 12-24 h to obtain the quaternary ammonium salt monomer VPIM-Br; S6. Preparation of quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM: Add the bacterial cellulose hydrogel bromide BC-Br prepared in S4 to deionized water, and then add the quaternary ammonium salt monomer VPIM-Br, cuprous bromide and 2,2'-bipyridine prepared in S5 in sequence, and stir at 25°C for 20-24h to obtain the quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM.

[0007] Preferably, the agar medium in S1 is prepared from the following raw materials in parts by weight: 100 parts of glucose, 10 parts of yeast powder, 20 parts of calcium carbonate, 15 parts of agar, and 1000 parts of deionized water, wherein the pH value of the agar medium is 6.78-6.82.

[0008] Preferably, the liquid culture medium in S2 is prepared from the following raw materials in parts by weight: 100 parts of glucose, 10 parts of yeast powder, 20 parts of calcium carbonate, and 1000 parts of deionized water, wherein the pH value of the liquid culture medium is 6.78-6.82.

[0009] Preferably, the volume ratio of the seed liquid to the fermentation medium in S3 is 1:10.

[0010] Preferably, the fermentation medium in S3 is prepared from the following raw materials in parts by weight: 20 parts of glucose, 10 parts of peptone, 5 parts of yeast powder, 2.7 parts of sodium hydrogen phosphate, 1.15 parts of citric acid, 0.25 parts of magnesium sulfate, and 1000 parts of deionized water, wherein the pH value of the fermentation medium is 5.98-6.02.

[0011] Preferably, the solid-liquid ratio of the bacterial cellulose hydrogel BC and 2-bromoisobutyl bromide in S4 is 130:1, the solid-liquid ratio of the bacterial cellulose hydrogel BC and dimethylformamide is 13:3, and the volume ratio of dimethylformamide to triethylamine is 300:8.

[0012] Preferably, the volume ratio of ethanol to deionized water in S4 is 1:1.

[0013] Preferably, the amount ratio of 1-vinylimidazole to 1-bromopentane in S5 is 1:1; the solid-liquid ratio of 1-vinylimidazole to cyclohexane is 47:500.

[0014] Preferably, the mass ratio of bacterial cellulose hydrogel bromide BC-Br, quaternary ammonium salt monomer VPIM-Br, cuprous bromide and 2,2'-bipyridine in S6 is 150-200:5:0.5:1, and the mass ratio of bacterial cellulose hydrogel bromide BC-Br to deionized water is 3-4:200.

[0015] Based on the same inventive concept, the present invention also provides an application of a quaternary ammonium salt-modified bacterial cellulose hydrogel, wherein the quaternary ammonium salt-modified bacterial cellulose hydrogel is used for wound dressing.

[0016] The above one or more technical solutions of the present invention have the following technical effects: Quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM gives bacterial cellulose hydrogel BC excellent antibacterial effect, making the antibacterial bacterial cellulose hydrogel BC have antibacterial and good biocompatibility in treating bacterial infected wounds, and accelerate wound healing. It can significantly reduce the bacteria in the wound; 2) The quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM prepared by the present invention has good biocompatibility and antibacterial properties. The preparation method adopts a bacterial fermentation method, which has low cost, simple preparation method, and is convenient for industrial mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below.

[0018] Figure 1 :Preparation process of quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM; Figure 2 : Scanning electron microscopy (SEM) images of bacterial cellulose hydrogel BC and quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM; Figure 3 : X-ray photoelectron spectroscopy XPS spectra of bacterial cellulose hydrogel BC, bacterial cellulose hydrogel bromide BC-Br and quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM; Figure 4 :Antibacterial effect of bacterial cellulose hydrogel BC and quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM on Escherichia coli; Figure 5 :Antibacterial effect of bacterial cellulose hydrogel BC and quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM on Staphylococcus aureus; Figure 6 :Antibacterial survival rate of bacterial cellulose hydrogel BC and quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM against Escherichia coli and Staphylococcus aureus; Figure 7 :Biocompatibility of bacterial cellulose hydrogel BC and quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM; Figure 8 :The effects of bacterial cellulose hydrogel BC and quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM on wound treatment in mice. DETAILED DESCRIPTION

[0019] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0020] Throughout the specification, unless otherwise specified, the terms used herein should be understood as the meanings commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art to which the present invention belongs. If there is a conflict, the present specification takes precedence. The preparation process of quaternary ammonium salt modified bacterial cellulose hydrogel is as follows Figure 1 shown.

[0021] Example 1 A method for preparing a quaternary ammonium salt-modified bacterial cellulose hydrogel comprises the following steps: S1: inoculating xylose Gluconacetobacter into an agar medium, placing it in an incubator, and inverting and culturing it at 30°C for 48 hours to obtain an activated strain; wherein the agar medium is prepared from the following raw materials in parts by weight: 100 g of glucose, 10 g of yeast powder, 20 g of calcium carbonate, 15 g of agar, and 1000 ml of deionized water, wherein the pH value of the agar medium is 6.78-6.82; S2: Take the activated bacteria obtained in S1 and inoculate it into a conical flask filled with liquid culture medium, place it in a bacterial culture shaker, and culture it at 30°C and 150 r / min for 48 h to obtain a seed solution; wherein the liquid culture medium is prepared from the following raw materials in parts by weight: 100 g of glucose, 10 g of yeast powder, 20 g of calcium carbonate, and 1000 g of deionized water, wherein the pH value of the liquid culture medium is 6.78-6.82; S3: 1.0 g of seed liquid was inoculated into 10 g of fermentation medium, placed in a thermostat, and cultured at 30°C for 7 days to obtain bacterial cellulose, which was soaked and washed with deionized water, boiled in a 0.1 mol / L sodium hydroxide solution, and washed with deionized water until the pH value was 6.98-7.02 to obtain bacterial cellulose hydrogel BC; the fermentation medium was prepared from the following raw materials in parts by weight: 20 g of glucose, 10 g of peptone, 5.0 g of yeast powder, 2.7 g of sodium hydrogen phosphate, 1.15 g of citric acid, 0.25 g of magnesium sulfate, and 1000 g of deionized water, wherein the pH value of the fermentation medium was 5.98-6.02; S4: Add 260 mg of bacterial cellulose hydrogel BC to 60 ml of dimethylformamide and 1.6 ml of triethylamine solution, introduce nitrogen, add 2.0 ml of 2-bromoisobutyl bromide under magnetic stirring in an ice-water bath, react at 0°C for 3 h, stir at 25°C for 24 h, and wash with a mixture of ethanol and deionized water in a volume ratio of 1:1 to obtain bacterial cellulose hydrogel bromide BC-Br; S5: Add 30 mmol 1-vinyl imidazole and 30 mmol 1-bromopentane to 30 ml cyclohexane, react at 50°C for 24 h, cool to room temperature, store in a -20°C refrigerator for 12 h, add 10 ml tetrahydrofuran, stir magnetically until a white solid precipitates, discard the supernatant, and vacuum dry at 40°C for 24 h to obtain the quaternary ammonium salt monomer VPIM-Br; S6: Add 75 mg of bacterial cellulose hydrogel bromide BC-Br to 5.0 ml of deionized water, and then add 2.5 mg of quaternary ammonium salt monomer VPIM-Br, 0.25 mg of cuprous bromide, and 0.5 mg of 2,2'-bipyridine. Stir at 25°C for 24 h to obtain quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM.

[0022] Example 2 Application of quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM for wound dressing: Cut the quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM into the size of the wound and apply it to the wound surface.

[0023] Comparative Example 1 A method for preparing bacterial cellulose hydrogel comprises the following steps: S1: inoculating xylose Gluconacetobacter into an agar medium, placing it in an incubator, and inverting and culturing it at 30°C for 48 hours to obtain an activated strain; wherein the agar medium is prepared from the following raw materials in parts by weight: 100 g of glucose, 10 g of yeast powder, 20 g of calcium carbonate, 15 g of agar, and 1000 ml of deionized water, wherein the pH value of the agar medium is 6.78-6.82; S2: Take the activated bacteria obtained in S1 and inoculate it into a conical flask filled with liquid culture medium, place it in a bacterial culture shaker, and culture it at 30°C and 150 r / min for 48 h to obtain a seed solution; wherein the liquid culture medium is prepared from the following raw materials in parts by weight: 100 g of glucose, 10 g of yeast powder, 20 g of calcium carbonate, and 1000 g of deionized water, wherein the pH value of the liquid culture medium is 6.78-6.82; S3: 1.0 g of seed liquid was inoculated into 10 g of fermentation medium, placed in a constant temperature box, and cultured at 30°C for 7 days to obtain bacterial cellulose, which was soaked and washed with deionized water, boiled in 0.1 mol / L sodium hydroxide solution, and washed with deionized water until the pH value was 6.98-7.02 to obtain bacterial cellulose hydrogel BC; the fermentation medium was prepared from the following raw materials in parts by weight: 20 g of glucose, 10 g of peptone, 5.0 g of yeast powder, 2.7 g of sodium hydrogen phosphate, 1.15 g of citric acid, 0.25 g of magnesium sulfate, and 1000 g of deionized water, wherein the pH value of the fermentation medium was 5.98-6.02.

[0024] Test Example 1 Morphological characterization of bacterial cellulose hydrogel BC and quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM: Scanning electron microscope (SEM) images of bacterial cellulose hydrogel BC and quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM were observed. Figure 2 As shown, (a) the interior of bacterial cellulose hydrogel BC is a fibrous porous network structure, and (b) the bacterial cellulose hydrogel BC-VPIM modified with quaternary ammonium salt has some additional protrusions compared to the bacterial cellulose hydrogel, and the pores are filled, indicating that the quaternary ammonium salt has successfully modified the bacterial cellulose hydrogel.

[0025] Test Example 2 X-ray photoelectron spectroscopy XPS characterization of bacterial cellulose hydrogel BC, bacterial cellulose hydrogel bromide BC-Br and quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM: Figure 3 As shown in the figure, compared with the bacterial cellulose hydrogel BC, the bacterial cellulose hydrogel bromide BC-Br showed the characteristic peak of Br 3d at 67.9 eV, indicating that Br was modified on the bacterial cellulose to prepare the bacterial cellulose hydrogel bromide BC-Br. At 67.9 eV and 401.3 eV, the quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM showed the characteristic peaks of Br 3d and N 1s, respectively, indicating that the quaternary ammonium salt successfully modified the bacterial cellulose hydrogel.

[0026] Test Example 3 In order to further verify the antibacterial properties of quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM, the quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM prepared in Example 1 and the bacterial cellulose hydrogel BC prepared in Comparative Example 1 were selected to respectively E. coli , Staphylococcus aureus S. aureus Tested for antibacterial activity. E. coli E. coli and Staphylococcus aureus S. aureus The order of magnitude is 1.0×10 6 CFU / ml. The study was conducted by plate counting method.

[0027] like Figure 4 As shown, Escherichia coli after the action of quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM E. coli The number is significantly less than the number of bacteria after the bacterial cellulose hydrogel BC, which verifies that the antibacterial property of quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM is stronger than that of bacterial cellulose hydrogel BC.

[0028] like Figure 5 As shown, Staphylococcus aureus after being acted on quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIMS. aureus The number is significantly less than that of bacteria after the action of bacterial cellulose hydrogel BC, which verifies that the antibacterial performance of bacterial cellulose hydrogel BC-VPIM modified with quaternary ammonium salt is better than that of bacterial cellulose hydrogel BC.

[0029] like Figure 6 As shown, the order of magnitude is 1.0×10 6 CFU / ml of Escherichia coli E. coli and Staphylococcus aureus S. aureus The quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM prepared in Example 1 was contacted respectively, and the antibacterial property of the quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM was verified by measuring the bacterial survival percentage after 1 hour of contact. Figure 6 It can be seen that the bacterial survival rate of bacterial cellulose hydrogel BC is 100%, while for quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM, the bacterial survival rate is reduced to less than 20%, indicating that the antibacterial performance of quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM is better than that of bacterial cellulose hydrogel BC.

[0030] Test Example 4 Biocompatibility test: Using mouse embryonic fibroblasts (NIH-3T3 cells) as model cells, its biocompatibility was evaluated by measuring its toxicity to mammalian cells. The effect of the hydrogel on the growth of NIH-3T3 cells was explored to evaluate the cytotoxicity of the hydrogel. The quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM prepared in Example 1 and the bacterial cellulose hydrogel BC prepared in Comparative Example 1 were selected to test their effects on the growth of NIH-3T3 cells. The bacterial cellulose hydrogel BC and the quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM were prepared into a 2.0 mg / ml solution, and diluted to 1.0 mg / ml. After incubating with NIH-3T3 cells for 24 h, the activity of the cells after the action of the bacterial cellulose hydrogel BC was tested using the CCK-8 kit. Figure 7 As shown, compared with the control group cells that were not exposed to bacterial cellulose hydrogel, the bacterial cellulose hydrogel BC was non-toxic to cells at 1.0 mg / ml. The quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM also showed no cytotoxicity, and the cell survival rate was over 80%, indicating that it has good biosafety. The above data show that the bacterial cellulose hydrogel BC and the quaternary ammonium salt-modified bacterial cellulose hydrogel BC-VPIM have excellent biocompatibility.

[0031] Test Example 5 In order to further verify the effect of quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM for wound dressing, the quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM prepared in Example 1 and the bacterial cellulose hydrogel BC prepared in Comparative Example 1 were selected to treat bacterial infection wounds in mice, respectively. Figure 8 As shown, bacterial cellulose hydrogel BC and quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM treated bacterial infection wounds in mice. On the 0th day of treatment, which was also the first day of modeling, the wound sizes treated by bacterial cellulose hydrogel BC and quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM were similar. On the 3rd day of treatment, the wound size of the quaternary ammonium salt modified bacterial cellulose hydrogel treatment group was smaller than that of the bacterial cellulose hydrogel group, indicating that the quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM had better antibacterial and wound healing properties than the bacterial cellulose hydrogel BC group. By the 7th day, it was obvious that the wound size of the quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM treatment group was smaller than that of the bacterial cellulose hydrogel BC group, further indicating that the quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM treatment group could inhibit bacteria and accelerate wound healing.

[0032] In summary, the quaternary ammonium salt modified bacterial cellulose hydrogel prepared by the present invention has excellent antibacterial effect, so that the antibacterial bacterial cellulose hydrogel has antibacterial effect and accelerates wound healing in treating bacterial infection wounds. The bacteria in the wound can be significantly reduced. It has good biocompatibility and antibacterial properties. The preparation method adopts the bacterial fermentation method, which is low in cost, simple in preparation method, and convenient for industrial batch production.

Claims

1. A method for preparing a quaternary ammonium salt-modified bacterial cellulose hydrogel, characterized in that: The steps include: S1. Activation of bacterial strains: inoculate xylose Gluconacetobacter into an agar medium, place it in a constant temperature box, and culture it at 30° C. for 24-72 hours to obtain activated bacterial strains; S2, preparation of seed solution: take the activated bacteria obtained in S1 and inoculate it into a conical flask filled with liquid culture medium, place it in a bacterial culture shaker, and culture it at 30°C and 150 r / min for 48-72h to obtain seed solution; S3, preparation of bacterial cellulose hydrogel BC: inoculate the seed solution obtained in S2 into the fermentation medium, place it in a constant temperature box, and culture it at 30°C for 7 days to obtain bacterial cellulose, soak and wash it with deionized water, boil it in 0.1 mol / L sodium hydroxide solution, and wash it with deionized water until the pH value is 6.98-7.02 to obtain bacterial cellulose hydrogel BC; S4. Preparation of bacterial cellulose hydrogel bromide BC-Br: Add bacterial cellulose hydrogel BC to dimethylformamide and triethylamine solution, introduce nitrogen, add 2-bromoisobutyl bromide under magnetic stirring in an ice-water bath, react at 0°C for 3 h, stir at 25°C for 24 h, wash with a mixed solution of ethanol and deionized water to obtain bacterial cellulose hydrogel bromide BC-Br; S5. Preparation of quaternary ammonium salt monomer VPIM-Br: 1-vinyl imidazole and 1-bromopentane were added to cyclohexane, reacted at 50°C for 24 h, cooled to room temperature, stored in a -20°C refrigerator for 12-24 h, added with tetrahydrofuran, magnetically stirred until a white solid precipitated, the supernatant was discarded, and vacuum dried at 30-40°C for 12-24 h to obtain the quaternary ammonium salt monomer VPIM-Br; S6. Preparation of quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM: Add the bacterial cellulose hydrogel bromide BC-Br prepared in S4 to deionized water, and then add the quaternary ammonium salt monomer VPIM-Br, cuprous bromide and 2,2'-bipyridine prepared in S5 in sequence, and stir at 25°C for 20-24h to obtain the quaternary ammonium salt modified bacterial cellulose hydrogel BC-VPIM.

2. The method for preparing the quaternary ammonium salt modified bacterial cellulose hydrogel according to claim 1, characterized in that: The agar medium in S1 is prepared from the following raw materials in parts by weight: 100 parts of glucose, 10 parts of yeast powder, 20 parts of calcium carbonate, 15 parts of agar, and 1000 parts of deionized water, wherein the pH value of the agar medium is 6.78-6.

82.

3. The method for preparing the quaternary ammonium salt modified bacterial cellulose hydrogel according to claim 1, characterized in that: The liquid culture medium in S2 is prepared from the following raw materials in parts by weight: 100 parts of glucose, 10 parts of yeast powder, 20 parts of calcium carbonate, and 1000 parts of deionized water, wherein the pH value of the liquid culture medium is 6.78-6.

82.

4. The method for preparing the quaternary ammonium salt modified bacterial cellulose hydrogel according to claim 1, characterized in that: The volume ratio of the seed liquid to the fermentation medium in S3 is 1:

10.

5. The method for preparing the quaternary ammonium salt modified bacterial cellulose hydrogel according to claim 1, characterized in that: The fermentation medium in S3 is prepared from the following raw materials in parts by weight: 20 parts of glucose, 10 parts of peptone, 5 parts of yeast powder, 2.7 parts of sodium hydrogen phosphate, 1.15 parts of citric acid, 0.25 parts of magnesium sulfate, and 1000 parts of deionized water, wherein the pH value of the fermentation medium is 5.98-6.

02.

6. The method for preparing the quaternary ammonium salt modified bacterial cellulose hydrogel according to claim 1, characterized in that: The solid-liquid ratio of the bacterial cellulose hydrogel BC and 2-bromoisobutyl bromide in S4 is 130:1, the solid-liquid ratio of the bacterial cellulose hydrogel BC and dimethylformamide is 13:3, and the volume ratio of dimethylformamide to triethylamine is 300:

8.

7. The method for preparing the quaternary ammonium salt modified bacterial cellulose hydrogel according to claim 1, characterized in that: The volume ratio of ethanol to deionized water in S4 is 1:

1.

8. The method for preparing the quaternary ammonium salt modified bacterial cellulose hydrogel according to claim 1, characterized in that: The mass ratio of 1-vinylimidazole to 1-bromopentane in S5 is 1:1; the solid-liquid ratio of 1-vinylimidazole to cyclohexane is 47:

500.

9. The method for preparing the quaternary ammonium salt modified bacterial cellulose hydrogel according to claim 1, characterized in that: The mass ratio of bacterial cellulose hydrogel bromide BC-Br, quaternary ammonium salt monomer VPIM-Br, cuprous bromide and 2,2'-bipyridine in S6 is 150-200:5:0.5:1, and the mass ratio of bacterial cellulose hydrogel bromide BC-Br to deionized water is 3-4:200.

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