Antibacterial dressing for promoting wound repair and regeneration and preparation method thereof

Abstract

The invention discloses an antibacterial dressing for promoting wound repair and regeneration and a preparation method thereof, and the preparation method comprises the following steps: adding hydrogen peroxide into a silk fibroin aqueous solution to prepare a silk fibroin aqueous solution premixed with hydrogen peroxide; horse radish peroxidase is added into the dopamine modified sodium alginate solution, and the dopamine modified sodium alginate solution premixed with horse radish peroxidase is prepared. Preparing a chondroitin sulfate composite solution; uniformly mixing the silk fibroin aqueous solution premixed with hydrogen peroxide, the dopamine modified sodium alginate solution premixed with horse radish peroxidase and the chondroitin sulfate composite solution. Hydrogel formed by cross-linking silk fibroin and chondroitin sulfate is used as a main body material of the dressing, and meanwhile, dopamine modified sodium alginate is introduced, so that the dressing has the photo-thermal antibacterial characteristic; magnesium oxide microspheres are introduced as a pore-foaming agent, micropores are formed in the dressing, and the liquid absorption property and the air permeability of the dressing are improved; the umbilical cord mesenchymal stem cell exosome is introduced, so that angiogenesis at the wound is promoted, and the wound healing promoting capability of the dressing is improved.

Description

Technical Field

[0001] This invention relates to the field of biomedicine, specifically to an antibacterial dressing that promotes wound repair and regeneration, and its preparation method. Background Technology

[0002] Skin wound infections are a common clinical problem, usually caused by microbial infection. Symptoms include redness, swelling, pain, purulent discharge, and fever, severely impacting patient recovery and quality of life. Current treatment for infected skin wounds primarily involves antibiotic therapy and other supportive treatments such as bandages and gauze. However, antibiotic therapy has limitations, including low bioavailability, drug resistance, and inappropriate treatment outcomes. Furthermore, some infected wounds may be caused by multiple pathogenic microorganisms, requiring different types of antibiotics, increasing the complexity of treatment. Supportive treatments such as bandages and gauze lack significant antibacterial and wound-healing abilities, resulting in limited clinical efficacy.

[0003] Therefore, there is an urgent need to develop a multifunctional biomedical dressing that combines antibacterial and anti-inflammatory properties with the ability to promote wound repair and regeneration. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of poor antibacterial effect and slow wound repair and regeneration speed of existing medical dressings, and to provide an antibacterial dressing that promotes wound repair and regeneration and its preparation method.

[0005] To achieve the above objectives, the present invention provides a method for preparing an antibacterial dressing that promotes wound repair and regeneration, comprising the following steps:

[0006] S1, Prepare a premixed hydrogen peroxide-based aqueous solution of silk fibroin:

[0007] Hydrogen peroxide was added to an aqueous solution of silk fibroin to prepare a premixed hydrogen peroxide aqueous solution of silk fibroin.

[0008] S2, prepare a premixed horseradish peroxidase-modified dopamine sodium alginate solution:

[0009] Dopamine is dispersed in an aqueous solution of sodium alginate, and under alkaline conditions, the dopamine is grafted onto the sodium alginate to prepare a dopamine-modified sodium alginate solution. Horseradish peroxidase is added to the dopamine-modified sodium alginate solution to prepare a dopamine-modified sodium alginate solution premixed with horseradish peroxidase.

[0010] S3, prepare chondroitin sulfate complex solution:

[0011] Magnesium oxide microspheres and umbilical cord mesenchymal stem cell exosomes were added to an aqueous solution of chondroitin sulfate and mixed to prepare a chondroitin sulfate complex solution.

[0012] S4, Prepare an antibacterial dressing that promotes wound repair and regeneration:

[0013] The premixed hydrogen peroxide-containing silk fibroin aqueous solution, the premixed horseradish peroxidase-modified dopamine sodium alginate solution, and the chondroitin sulfate composite solution are mixed to prepare the antibacterial dressing that promotes wound repair and regeneration.

[0014] Optionally, in step S1 above, the silk fibroin aqueous solution is prepared by dissolving lyophilized silk fibroin in deionized water, and the mass concentration of silk fibroin is 1% to 5%.

[0015] Optionally, in step S1 above, the volume concentration of hydrogen peroxide in the premixed hydrogen peroxide aqueous solution of silk fibroin is 0.1% to 1%.

[0016] Optionally, in step S2 above, the mass ratio of dopamine to sodium alginate is 1:500 to 1:1000.

[0017] Optionally, in step S2 above, the specific preparation method of the dopamine-modified sodium alginate solution is as follows: dispersing dopamine in an aqueous sodium alginate solution, adjusting the pH of the solution to 8-9, stirring at room temperature for 24-48 hours, and obtaining the dopamine-modified sodium alginate solution.

[0018] Optionally, in step S2 above, the concentration of horseradish peroxidase in the dopamine-modified sodium alginate solution containing premixed horseradish peroxidase is 100 U / mL to 500 U / mL.

[0019] Optionally, in step S3 above, the mass concentration of chondroitin sulfate in the aqueous solution is 1% to 10%.

[0020] Optionally, in step S3 above, the particle size of the magnesium oxide microspheres is 30 nm to 50 nm, and the mass concentration is 0.1% to 1%.

[0021] Optionally, in step S4 above, the premixed hydrogen peroxide-containing silk fibroin aqueous solution, the premixed horseradish peroxidase-modified dopamine sodium alginate solution, and the chondroitin sulfate composite solution are mixed in a ratio of 1:1:0.5 to 1:1:2.

[0022] The present invention also provides an antibacterial dressing for promoting wound repair and regeneration prepared by the above preparation method. The dressing uses a hydrogel formed by cross-linking silk fibroin and chondroitin sulfate as the main material of the dressing. At the same time, dopamine-modified sodium alginate is introduced to give the dressing photothermal antibacterial properties. Magnesium oxide microspheres are introduced as pore-forming agents to form micropores inside the dressing, thereby improving the dressing's absorbency and breathability. Umbilical cord mesenchymal stem cell exosomes are introduced to promote angiogenesis at the wound site and improve the dressing's wound healing ability.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) An antibacterial dressing that promotes wound repair and regeneration was prepared by introducing dopamine-modified sodium alginate and magnesium oxide microspheres into the hydrogel, exhibiting excellent antibacterial properties:

[0025] Because dopamine has photothermal properties, this invention modifies sodium alginate with dopamine to impart these properties. Furthermore, the dopamine-modified sodium alginate is incorporated into a hydrogel, giving the hydrogel photothermal properties as well. Under near-infrared laser irradiation, the hydrogel can exert a photothermal effect to effectively inhibit bacteria, thus giving the dressing a photothermal antibacterial effect.

[0026] In the slightly acidic environment of the skin, magnesium oxide microspheres can react with water to form magnesium ions with antibacterial properties, further improving the antibacterial properties of the dressing of the present invention.

[0027] (2) Furthermore, by introducing mesenchymal stem cell exosomes and magnesium oxide microspheres into the hydrogel, the dressing exhibits excellent pro-angiogenic properties:

[0028] Mesenchymal stem cell exosomes are important cell exosomes that can promote cell proliferation and angiogenesis. In this invention, a synergistic effect was discovered between mesenchymal stem cell exosomes and magnesium oxide microspheres; when used in combination, they exhibit a better pro-angiogenic effect than when used alone.

[0029] (3) In this invention, silk fibroin, chondroitin sulfate, dopamine-modified sodium alginate, magnesium oxide microspheres, and mesenchymal stem cell exosomes have a synergistic effect, jointly regulating the antibacterial and angiogenic properties of the dressing:

[0030] In this invention, silk fibroin, chondroitin sulfate, and dopamine-modified sodium alginate undergo cross-linking to form a hydrogel with a certain porosity. Magnesium oxide microspheres and mesenchymal stem cell exosomes are loaded into the pores of the hydrogel through electrostatic adsorption. When the ratio and reaction conditions of silk fibroin, chondroitin sulfate, and dopamine-modified sodium alginate are changed, the porosity of the hydrogel formed by the cross-linking of the three components is also changed accordingly. The release rate of magnesium oxide microspheres and mesenchymal stem cell exosomes loaded in the pores of the hydrogel is also changed accordingly. The antibacterial properties produced by magnesium oxide microspheres and the angiogenesis-promoting properties synergistically produced by magnesium oxide microspheres and mesenchymal stem cell exosomes are adjusted accordingly. Thus, the silk fibroin, chondroitin sulfate, dopamine-modified sodium alginate, magnesium oxide microspheres, and mesenchymal stem cell exosomes of this invention can jointly regulate the antibacterial and angiogenesis-promoting properties of the dressing, and the components have a synergistic effect. Attached Figure Description

[0031] Figure 1 This is a schematic diagram illustrating the preparation principle of the antibacterial dressing for promoting wound repair and regeneration according to the present invention.

[0032] Figure 2 The figure shows the effect of the dressings prepared in Example 1, Comparative Example 1, and Comparative Example 2 on the expression of CD31 and KDR.

[0033] Figure 3 The figures show the in vitro antibacterial test results of the antibacterial dressings that promote wound repair and regeneration prepared in Examples 1-4. Detailed Implementation

[0034] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0035] This invention provides an antibacterial dressing that promotes wound repair and regeneration. The main material of the dressing is a hydrogel formed by cross-linking silk fibroin and chondroitin sulfate. Dopamine-modified sodium alginate is introduced to give the dressing photothermal antibacterial properties. Magnesium oxide microspheres are introduced as a pore-forming agent to create micropores within the dressing, improving its absorbency and breathability. Umbilical cord mesenchymal stem cell exosomes are introduced to promote angiogenesis at the wound site, thereby enhancing the dressing's wound-healing ability.

[0036] Silk fibroin is a fibrous protein with excellent biological and mechanical properties. It can accelerate skin healing, but it lacks certain adhesiveness. Chondroitin sulfate is an acidic, viscous polymer with good adhesiveness. A hydrogel made by cross-linking silk fibroin and chondroitin sulfate is used as the main material of the dressing. This makes the dressing have excellent biocompatibility and mechanical strength, as well as good adhesiveness, allowing it to adhere tightly to the skin without the need for adhesives.

[0037] Dopamine possesses excellent photothermal properties. This invention modifies sodium alginate by modifying it with dopamine, thereby giving the modified sodium alginate photothermal properties. Furthermore, the dopamine-modified sodium alginate is introduced into a hydrogel, endowing the hydrogel with photothermal properties. Under near-infrared laser irradiation, the hydrogel can exert a photothermal effect to effectively inhibit bacteria, giving the dressing a photothermal antibacterial effect.

[0038] Magnesium oxide is an excellent antibacterial agent. Upon contact with wound exudate, it dissolves to form magnesium ions, which have antibacterial properties. Furthermore, magnesium oxide acts as a pore-forming agent, creating pores within the hydrogel after dissolution. This further promotes the absorption of wound exudate by the hydrogel, enhancing its absorbency and preventing the spread of wound exudate that could lead to infection.

[0039] Mesenchymal stem cell exosomes are important cell exosomes that can promote cell proliferation and angiogenesis. This patent found that when mesenchymal stem cell exosomes are used in combination with magnesium oxide, they exhibit a better pro-angiogenic effect than when used alone, thus promoting wound healing more effectively.

[0040] This invention combines the advantages of silk fibroin, chondroitin sulfate, sodium alginate, magnesium oxide microspheres, and human umbilical cord mesenchymal stem cell exosomes to prepare an antibacterial dressing with good biocompatibility and photothermal properties. It can promote the proliferation of human umbilical vein endothelial cells (HUVECs) and promote angiogenesis. When applied to infected skin wounds, it has achieved good antibacterial and repair-promoting effects.

[0041] Furthermore, the present invention provides a method for preparing the above-mentioned antibacterial dressing that promotes wound repair and regeneration, comprising the following steps:

[0042] S1, Prepare a premixed hydrogen peroxide-based aqueous solution of silk fibroin:

[0043] Hydrogen peroxide was added to an aqueous solution of silk fibroin to prepare a premixed hydrogen peroxide aqueous solution of silk fibroin.

[0044] S2, prepare a premixed horseradish peroxidase-modified dopamine sodium alginate solution:

[0045] Dopamine is dispersed in an aqueous solution of sodium alginate, and under alkaline conditions, the dopamine is grafted onto the sodium alginate to prepare a dopamine-modified sodium alginate solution. Horseradish peroxidase is added to the dopamine-modified sodium alginate solution to prepare a dopamine-modified sodium alginate solution premixed with horseradish peroxidase.

[0046] S3, prepare chondroitin sulfate complex solution:

[0047] Magnesium oxide microspheres and umbilical cord mesenchymal stem cell exosomes were added to an aqueous solution of chondroitin sulfate and mixed to prepare a chondroitin sulfate complex solution.

[0048] S4, Prepare an antibacterial dressing that promotes wound repair and regeneration:

[0049] The premixed hydrogen peroxide-containing silk fibroin aqueous solution, the premixed horseradish peroxidase-modified dopamine sodium alginate solution, and the chondroitin sulfate composite solution are mixed to prepare the antibacterial dressing that promotes wound repair and regeneration.

[0050] This invention uses hydrogen peroxide and horseradish peroxidase as crosslinking agents to crosslink silk fibroin, dopamine-modified sodium alginate, and chondroitin sulfate to form a hydrogel. Hydrogen peroxide and horseradish peroxidase have the advantages of rapid gelation and no toxic side effects; they rapidly initiate a crosslinking reaction upon contact. Due to their rapid reaction, if they are not dispersed evenly in the system in a timely manner, localized crosslinking can occur. This invention addresses this by pre-mixing hydrogen peroxide and horseradish peroxidase in different hydrogel raw material solutions during the preparation process. This promotes the dispersion of hydrogen peroxide and horseradish peroxidase in the system, avoids localized crosslinking caused by uneven dispersion, and improves the crosslinking uniformity of the prepared hydrogel.

[0051] In this invention, silk fibroin, dopamine-modified sodium alginate, and chondroitin sulfate cross-link to form a hydrogel, and magnesium oxide and umbilical cord mesenchymal stem cell exosomes are loaded in the hydrogel through electrostatic adsorption. Figure 1 As shown, the hydrogel of the present invention possesses a quadruple cross-linking network: the first cross-linking network is formed by cross-linking between the amino groups of silk fibroin and the NHS groups of chondroitin sulfate; the second cross-linking network is formed by cross-linking between the tyrosine groups of silk fibroin and the catechol groups of dopamine-modified sodium alginate; the third cross-linking network is formed by cross-linking between the tyrosine groups of each silk fibroin; and the fourth cross-linking network is formed by cross-linking between the catechol groups of each dopamine-modified sodium alginate. The formation of the quadruple cross-linking network further improves the mechanical properties of the dressing.

[0052] The present invention will be further described in detail below with reference to the embodiments.

[0053] Example 1: Preparation of an antibacterial dressing that promotes wound repair and regeneration

[0054] This embodiment provides a method for preparing an antibacterial dressing that promotes wound repair and regeneration, including the following steps:

[0055] 1. Preparation of freeze-dried silk fibroin:

[0056] (1) Place the silkworm cocoons in a 0.5wt% Na2CO3 solution (purchased from Sigma) and degumm them in a 100℃ water bath for 30 minutes. Repeat this process three times. Then dry them at 60℃ for 6 hours to obtain dried silk.

[0057] (2) Add calcium chloride (purchased from Sigma) and ethanol (purchased from Sigma) to water to prepare a ternary solution with a molar ratio of calcium chloride:water:ethanol = 1:8:2. Heat the ternary solution to 100°C, and add silk to the ternary solution with a mass ratio of silk:ternary solution = 1:25. Stir until the silk is completely dissolved, and centrifuge at room temperature to remove insoluble impurities.

[0058] (3) The supernatant obtained by centrifugation was placed into a dialysis bag with a molecular weight of 3500 and dialyzed under distilled water for 2 days. The resulting solution was then freeze-dried and stored to obtain freeze-dried silk fibroin.

[0059] 2. Prepare a premixed hydrogen peroxide aqueous solution of silk fibroin:

[0060] Prepare a 5% (wt / v) aqueous solution of silk fibroin by adding a certain amount of hydrogen peroxide solution (purchased from Sigma) to the solution until the final concentration of hydrogen peroxide is 0.1% v / v, and stirring until the mixture is homogeneous to obtain a premixed hydrogen peroxide aqueous solution of silk fibroin.

[0061] 3. Preparation of dopamine-modified sodium alginate solution premixed with horseradish peroxidase:

[0062] (1) Prepare a 2% (wt / v) sodium alginate (purchased from Sigma) aqueous solution, and add dopamine (dopamine hydrochloride, purchased from Sigma) to the solution to achieve a final dopamine concentration of 2 g / L. That is, the mass ratio of dopamine to sodium alginate is 1:1000.

[0063] (2) Adjust the pH of the solution to 8.5 with sodium hydroxide solution and stir the reaction at room temperature for 24 hours. During this period, the color of the solution gradually changes from colorless to brown and finally to black.

[0064] (3) After the reaction is complete, add horseradish peroxidase (purchased from Sigma) to the solution to make the final concentration of horseradish peroxidase reach 200 U / mL, stir and mix to obtain a dopamine-modified sodium alginate solution of premixed horseradish peroxidase.

[0065] 4. Preparation of chondroitin sulfate complex solution:

[0066] (1) Prepare a 5% (wt / v) chondroitin sulfate (purchased from Sigma) aqueous solution, add magnesium oxide microspheres with a particle size of 30nm to 50nm (purchased from Yumu (Ningbo) New Materials Co., Ltd.) to the solution, so that the final concentration of magnesium oxide microspheres reaches 1% (wt / v), and stir to disperse evenly;

[0067] (2) Add human umbilical cord mesenchymal stem cell exosomes (purchased from Enzekangtai Biotechnology Co., Ltd.) to the solution to make the concentration of human umbilical cord mesenchymal stem cell exosomes reach 100 μg / mL, stir and mix well to obtain chondroitin sulfate complex solution.

[0068] 5. Preparation of antibacterial dressings that promote wound healing and regeneration

[0069] The premixed hydrogen peroxide-containing silk fibroin aqueous solution prepared in step 2, the premixed horseradish peroxidase-modified dopamine sodium alginate solution prepared in step 3, and the chondroitin sulfate composite solution prepared in step 4 were mixed in a ratio of 1:1:1 and allowed to stand at room temperature for 5 minutes to obtain the antibacterial dressing that promotes wound repair and regeneration in this embodiment.

[0070] Example 2

[0071] The difference between Example 2 and Example 1 is that the concentration of the silk fibroin aqueous solution in step 2 is 10% (wt / v).

[0072] Example 3

[0073] The difference between Example 3 and Example 1 is that the concentration of the chondroitin sulfate aqueous solution in step 4 is 10% (wt / v).

[0074] Example 4

[0075] The difference between Example 4 and Example 1 is that the mass ratio of dopamine to sodium alginate in step 3 is 1:500.

[0076] Comparative Example 1

[0077] The difference between Comparative Example 1 and Example 1 is that only magnesium oxide microspheres were added to the chondroitin sulfate aqueous solution in step 4.

[0078] Comparative Example 2

[0079] The difference between Comparative Example 2 and Example 1 is that only human umbilical cord mesenchymal stem cell exosomes were added to the chondroitin sulfate aqueous solution in step 4.

[0080] The dressings prepared in Example 1, Comparative Example 1, and Comparative Example 2 were subjected to CD31 and KDR expression experiments. CD31 (PECAM-1) is a specific marker molecule on the surface of vascular endothelial cells, mainly involved in the adhesion and junction between endothelial cells and the formation of blood vessels. Its expression level directly reflects the activation state and angiogenesis capacity of endothelial cells. KDR (VEGFR-2) is the main functional receptor of vascular endothelial growth factor, mediating the VEGF signaling pathway and regulating the proliferation, migration, survival, and angiogenesis of endothelial cells. It is a key molecular marker for evaluating angiogenic activity. Detecting changes in the expression of CD31 and KDR genes can effectively assess the regulatory effects of magnesium oxide and human umbilical cord mesenchymal stem cell exosomes on angiogenesis.

[0081] HUVECs were inoculated onto dressings prepared in Example 1 (magnesium oxide + exosomes), Comparative Example 1 (magnesium oxide), and Comparative Example 2 (exosomes) (n=3), respectively. The control group consisted of HUVECs inoculated onto complete culture medium. The culture was performed for 48 h to detect CD31 and KDR expression. Total RNA was extracted using TRIzol reagent, and after determining its concentration and purity, the mRNA was reverse transcribed into cDNA. Using cDNA as a template and GAPDH as an internal reference gene, quantitative real-time PCR analysis was performed using the SYBR Green assay. -ΔΔCT The method is used for data analysis.

[0082] The primer sequences are as follows:

[0083] SEQ ID NO.1: CD31 forward primer: 5'-CTACAACACCTAGTACCCTTGGA-3'

[0084] SEQ ID NO.2: CD31 reverse primer: 5'-GGTGAACACTGTGCTGATTACA-3'

[0085] SEQ ID NO.3: KDR forward primer: 5'-GGCCCAATAATCAGAGTGGCA-3'

[0086] SEQ ID NO.4: KDR reverse primer: 5'-CCAGTGTCATTTCCGATCACTTT-3'

[0087] like Figure 2 As shown, the expression levels of CD31 and KDR in the magnesium oxide + exosome group were higher than those in the control group, indicating that magnesium oxide + exosomes have excellent angiogenesis-promoting effects. Furthermore, the angiogenesis in the magnesium oxide + exosome group was significantly better than that in the magnesium oxide group and the exosome group alone, suggesting that magnesium oxide and human umbilical cord mesenchymal stem cell exosomes exert a synergistic effect in promoting angiogenesis.

[0088] The antibacterial dressings for promoting wound repair and regeneration prepared in Examples 1-4 were subjected to in vitro antibacterial performance experiments. The antibacterial activity of the dressings was evaluated using *Escherichia coli* and *Staphylococcus aureus*. The antibacterial dressings for promoting wound repair and regeneration prepared in Examples 1-4 were placed in petri dishes. An equal volume of sterile saline was added to the control group, and each group was inoculated with an equal volume of bacterial suspension (1×10⁻⁶). 6 CFU / mL), near-infrared light irradiation (808nm, 2.0W / cm²) 2 After 5 minutes, incubate at 37°C for 24 hours. Collect the culture medium from each group, perform serial dilutions, and plate onto LB agar plates. Figure 3 As shown, the antibacterial dressing of the present invention has excellent antibacterial effect.

[0089] In summary, this invention combines the advantageous properties of hydrogels containing silk fibroin and chondroitin sulfate, introduces dopamine-modified sodium alginate to impart photothermal properties, utilizes magnesium oxide microspheres as a pore-forming agent, and leverages the angiogenesis-promoting properties of human umbilical cord mesenchymal stem cell exosomes to prepare an antibacterial dressing that promotes wound repair and regeneration. This dressing exhibits good biocompatibility and photothermal properties, demonstrates excellent angiogenic activity, and provides a favorable moist environment for tissue repair. Under near-infrared laser irradiation, the photothermal effect of the material effectively inhibits bacteria, providing a novel, non-antibiotic-dependent antibacterial treatment method for skin infection wound repair.

[0090] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A method for preparing an antibacterial dressing that promotes wound repair and regeneration, characterized in that, Includes the following steps: S1, Prepare a premixed hydrogen peroxide-based aqueous solution of silk fibroin: Hydrogen peroxide was added to an aqueous solution of silk fibroin to prepare a premixed hydrogen peroxide aqueous solution of silk fibroin. S2, prepare a premixed horseradish peroxidase-modified dopamine sodium alginate solution: Dopamine is dispersed in an aqueous solution of sodium alginate, and under alkaline conditions, the dopamine is grafted onto sodium alginate to prepare a dopamine-modified sodium alginate solution; horseradish peroxidase is added to the dopamine-modified sodium alginate solution to prepare a dopamine-modified sodium alginate solution premixed with horseradish peroxidase. S3, prepare chondroitin sulfate complex solution: Magnesium oxide microspheres and umbilical cord mesenchymal stem cell exosomes were added to an aqueous solution of chondroitin sulfate and mixed well to prepare a chondroitin sulfate complex solution. S4, Prepare an antibacterial dressing that promotes wound repair and regeneration: The premixed hydrogen peroxide-containing silk fibroin aqueous solution, the premixed horseradish peroxidase-modified dopamine sodium alginate solution, and the chondroitin sulfate composite solution are mixed to prepare the antibacterial dressing that promotes wound repair and regeneration.

2. The method for preparing the antibacterial dressing for promoting wound repair and regeneration as described in claim 1, characterized in that, In step S1, the silk fibroin aqueous solution is prepared by dissolving lyophilized silk fibroin in deionized water, and the mass concentration of silk fibroin is 1% to 5%.

3. The method for preparing the antibacterial dressing for promoting wound repair and regeneration as described in claim 1, characterized in that, In step S1, the volume concentration of hydrogen peroxide in the premixed hydrogen peroxide aqueous solution of silk fibroin is 0.1% to 1%.

4. The method for preparing the antibacterial dressing for promoting wound repair and regeneration as described in claim 1, characterized in that, In step S2, the mass ratio of dopamine to sodium alginate is 1:500 to 1:1000.

5. The method for preparing the antibacterial dressing for promoting wound repair and regeneration as described in claim 1, characterized in that, In step S2, the specific preparation method of the dopamine-modified sodium alginate solution is as follows: Dopamine was dispersed in an aqueous solution of sodium alginate, the pH of the solution was adjusted to 8-9, and the mixture was stirred at room temperature for 24-48 hours to obtain the dopamine-modified sodium alginate solution.

6. The method for preparing the antibacterial dressing for promoting wound repair and regeneration as described in claim 1, characterized in that, In step S2, the concentration of horseradish peroxidase in the dopamine-modified sodium alginate solution containing premixed horseradish peroxidase is 100 U / mL to 500 U / mL.

7. The method for preparing the antibacterial dressing for promoting wound repair and regeneration as described in claim 1, characterized in that, In step S3, the chondroitin sulfate aqueous solution has a chondroitin sulfate mass concentration of 1% to 10%.

8. The method for preparing the antibacterial dressing for promoting wound repair and regeneration as described in claim 1, characterized in that, In step S3, the magnesium oxide microspheres have a particle size of 30 nm to 50 nm and a mass concentration of 0.1% to 1%.

9. The method for preparing the antibacterial dressing for promoting wound repair and regeneration as described in claim 1, characterized in that, In step S4, the premixed hydrogen peroxide-containing silk fibroin aqueous solution, the premixed horseradish peroxidase-modified dopamine sodium alginate solution, and the chondroitin sulfate composite solution are mixed in a ratio of 1:1:0.5 to 1:1:

2.

10. An antibacterial dressing that promotes wound repair and regeneration, characterized in that, It is prepared by any one of the preparation methods described in claims 1 to 9.

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