Antibacterial healing-promoting hydrocolloid wound surface auxiliary material and preparation method thereof

Abstract

The invention discloses an antibacterial healing-promoting hydrocolloid wound surface auxiliary material and a preparation method thereof, and the antibacterial healing-promoting hydrocolloid wound surface auxiliary material comprises the following components by mass: 30-50 parts of a hydrocolloid matrix; 5 to 12 parts of a modified chitosan-graphene composite antibacterial agent; 3-8 parts of plant source healing promoting active peptide; 4 to 10 parts of a poly gamma-glutamic acid grafted hyaluronic acid moisturizing synergist; 2-6 parts of a plasticizer; 1-4 parts of an adhesion regulator; 0.1 to 0.5 part of a preservative; 15 to 30 parts of deionized water; the antibacterial performance is excellent, the modified chitosan-graphene composite antibacterial agent is adopted, the antibacterial activity of chitosan is enhanced through quaternization modification, then chitosan is compounded with graphene, on one hand, the water solubility and the antibacterial activity of chitosan are enhanced, on the other hand, the high specific surface area and the charge effect of graphene are utilized, and the antibacterial performance of chitosan is improved. The damage capability of the antibacterial agent to bacterial cell membranes is further improved, broad-spectrum and efficient antibacterial effects are achieved, the risk of drug resistance is avoided, and the biological safety is high.

Description

Technical Field

[0001] This invention belongs to the field of medical biomaterials technology, specifically an antibacterial and healing-promoting hydrocolloid wound dressing and its preparation method. Background Technology

[0002] Wound healing is a complex physiological process involving multiple stages, including inflammatory response, cell proliferation, and tissue remodeling. Wound dressings, as important medical materials for wound repair, have the core functions of protecting the wound, absorbing exudate, inhibiting bacterial infection, and promoting wound healing. Hydrocolloid dressings, due to their excellent biocompatibility, water absorption, and moisture retention, can create a suitable healing microenvironment for the wound and are widely used in the care of chronic ulcers, burns, abrasions, and other wounds.

[0003] However, existing hydrocolloid wound dressings still have many shortcomings: on the one hand, their antibacterial properties are limited, making it difficult to effectively inhibit the growth of common wound pathogens (such as Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa), which can easily lead to aggravated wound infection and delay the healing process; on the other hand, their healing-promoting activity is weak, and they cannot actively regulate the proliferation and differentiation of wound healing-related cells (such as fibroblasts and endothelial cells), resulting in poor repair effects on chronic, refractory wounds. In addition, some hydrocolloid dressings have problems with improper adhesion; excessive adhesion can easily cause secondary damage to the wound, while insufficient adhesion will prevent them from being firmly fixed to the wound.

[0004] To address the aforementioned issues, existing technologies often improve hydrocolloid dressings by adding antibacterial components such as antibiotics and silver ions, or healing-promoting components such as growth factors. However, the overuse of antibiotics can easily lead to the emergence of drug-resistant bacteria, and long-term use of silver ions may cause cumulative toxicity in the human body; growth factors have poor stability, are easily degraded by enzymes, and have high production costs, making large-scale application difficult. Therefore, developing a hydrocolloid wound dressing that combines highly efficient and safe antibacterial properties with significant healing-promoting activity, and whose preparation process is simple and cost-controllable, has significant clinical application value.

[0005] Based on this, an antibacterial and healing-promoting hydrocolloid wound dressing and its preparation method were designed. Summary of the Invention

[0006] In view of the above situation and to overcome the defects of the prior art, the present invention provides an antibacterial and healing-promoting hydrocolloid wound dressing and its preparation method, which effectively solves the problems mentioned in the background.

[0007] To achieve the above objectives, the present invention provides the following technical solution: an antibacterial and healing-promoting hydrocolloid wound dressing, comprising the following components in parts by weight: Hydrocolloid matrix: 30-50 parts; Modified chitosan-graphene composite antibacterial agent: 5-12 parts; Plant-derived healing-promoting active peptides: 3-8 parts; Poly-γ-glutamic acid grafted hyaluronic acid moisturizing synergist: 4-10 parts; Plasticizer: 2-6 parts; Adhesion modifier: 1-4 parts; Preservative: 0.1-0.5 parts; Deionized water: 15-30 parts.

[0008] Preferably, the hydrocolloid matrix is ​​a mixture of sodium carboxymethyl cellulose, gelatin, and pectin in a mass ratio of 2:1:0.5-1.5; The plasticizer is a mixture of glycerin and polyethylene glycol 400 in a mass ratio of 1:1-2; The adhesion modifier is a mixture of povidone K30 and xanthan gum in a mass ratio of 3:1; The preservative is phenoxyethanol.

[0009] Preferably, the modified chitosan-graphene composite antibacterial agent is prepared as follows: S1. Preparation of quaternized modified chitosan Add 5-8 parts of chitosan to 40-60 parts of acetic acid solution with a mass fraction of 2%-5%, and stir to dissolve at 35-45℃ and 150-200 rpm to obtain a chitosan solution. Slowly add 8-12 parts of 30% 3-chloro-2-hydroxypropyltrimethylammonium chloride solution to the chitosan solution. After the addition is complete, adjust the pH of the system to 8.0-9.0, raise the temperature to 60-70℃, and keep the reaction at this temperature for 4-6 hours. After the reaction is complete, pour the reaction solution into 100-150 parts of acetone to precipitate, filter and collect the precipitate, wash it 3-5 times with anhydrous ethanol, and then dry it in a vacuum drying oven at 60-70℃ for 8-12 hours to obtain quaternized modified chitosan. S2, Preparation of graphene oxide Using a modified Hummers method, 2-3 parts of graphite powder were added to 50-70 parts of 98% concentrated sulfuric acid, and stirred for 30-40 minutes at 0-5℃ and 80-100 rpm. 6-8 parts of potassium permanganate were slowly added, controlling the temperature to not exceed 10℃, and stirring continued for 1-2 hours. The temperature was then raised to 35-40℃ and maintained for 2-3 hours. 100-120 parts of deionized water were slowly added, and the temperature was raised to 90-95℃ and maintained for 30-40 minutes. After the reaction, 20-30 parts of 30% hydrogen peroxide solution were added, and the mixture was stirred for 10-15 minutes until the solution turned bright yellow. The reaction solution was centrifuged, the precipitate was collected, washed 2-3 times with 5% hydrochloric acid solution, then washed with deionized water until neutral, and finally dried in a vacuum drying oven at 50-60℃ for 6-8 hours to obtain graphene oxide. S3, Preparation of modified chitosan-graphene composite antibacterial agent Add 3-5 parts of quaternized modified chitosan to 30-50 parts of deionized water and stir to dissolve at 40-50℃ and 180-220 rpm to obtain a quaternized modified chitosan solution. Add 1-2 parts of graphene oxide to 20-30 parts of deionized water and ultrasonically disperse for 20-30 minutes at an ultrasonic power of 300-400 watts to obtain a graphene oxide dispersion. Slowly add the graphene oxide dispersion to the quaternized modified chitosan solution and stir to react for 2-3 hours at 50-60℃ and 200-250 rpm. After the reaction, centrifuge the reaction solution at 8000-10000 rpm for 15-20 minutes, collect the precipitate, wash it 2-3 times with deionized water, dry it in a vacuum drying oven at 60-70℃ for 8-10 hours, and pulverize it through a 100-mesh sieve to obtain a modified chitosan-graphene composite antibacterial agent.

[0010] Preferably, the preparation method of the plant-derived healing-promoting active peptide is as follows: S1. Pretreatment of Eucommia ulmoides leaf raw materials Select dried Eucommia ulmoides leaves, pulverize them and pass them through a 60-mesh sieve. Take 5-10 parts of Eucommia ulmoides leaf powder and add it to 40-60 parts of deionized water. Stir and extract for 1-2 hours at 50-60℃ and 120-150 rpm. Filter to remove residue to obtain crude Eucommia ulmoides leaf extract. Concentrate the crude extract under reduced pressure at 40-50℃ and a vacuum of 0.06-0.08 MPa to 1 / 3-1 / 2 of the original volume to obtain concentrated Eucommia ulmoides leaf extract. S2. Enzymatic hydrolysis to prepare crude active peptides Add 0.3-0.6 parts of a complex protease, composed of papain and alkaline protease in a 1:1 mass ratio, to the concentrated Eucommia ulmoides leaf extract. Adjust the pH of the system to 6.5-7.5 and hydrolyze the enzyme at 50-60℃ and 150-180 rpm for 2-3 hours. After hydrolysis, heat to 90-95℃ and incubate for 10-15 minutes to inactivate the enzyme. After cooling to room temperature, centrifuge at 6000-8000 rpm for 10-15 minutes and collect the supernatant to obtain a crude solution of active peptides. S3. Purification yields plant-derived healing-promoting active peptides. The crude active peptide solution was initially purified by passing it through a macroporous resin adsorption column. Impurities were first eluted with deionized water, followed by elution with a 20%-30% (w / w) ethanol solution. The eluent was collected. The eluent was concentrated under reduced pressure at 35-45℃ and a vacuum of 0.06-0.08 MPa to remove ethanol. The concentrate was further purified by passing it through a gel filtration chromatography column with deionized water as the mobile phase at a flow rate of 0.5-1.0 mL / min. The eluent corresponding to the main peak was collected. The collected eluent was freeze-dried at -40 to -30℃ and a vacuum of 10-30 Pa for 24-36 hours to obtain the plant-derived healing-promoting active peptide.

[0011] Preferably, the preparation method of the polyγ-glutamic acid-grafted hyaluronic acid moisturizing synergist is as follows: Add 2-4 parts of polyγ-glutamic acid and 3-5 parts of hyaluronic acid to 30-50 parts of deionized water and stir to dissolve at 45-55℃ and 180-220 rpm to obtain a mixed solution. Add 0.2-0.4 parts of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and 0.1-0.3 parts of N-hydroxysuccinimide to the mixed solution and adjust the pH of the system to 5.0-6.0. React at room temperature and 150-200 rpm for 3-5 hours. After the reaction, put the reaction solution into a dialysis bag with a molecular weight cutoff of 8000-14000 Daltons and dialyze with deionized water for 24-36 hours, changing the deionized water 3-4 times during the process. Freeze-dry the dialyzed solution at -40 to -30℃ and a vacuum of 10-30 Pa for 24-36 hours to obtain a polyγ-glutamic acid-grafted hyaluronic acid moisturizing synergist.

[0012] A method for preparing an antibacterial and healing-promoting hydrocolloid wound dressing includes the following steps: Step 1: Preparation of hydrocolloid matrix premix Add 30-50 parts by weight of the hydrocolloid matrix to 15-30 parts of deionized water and stir to dissolve at 60-70℃ and 200-250 rpm. Then add 2-6 parts of plasticizer and continue stirring for 20-30 minutes to obtain the hydrocolloid matrix premix.

[0013] Step 2: Add the functional ingredients and mix well. Add 5-12 parts of modified chitosan-graphene composite antibacterial agent, 4-10 parts of polyγ-glutamic acid grafted hyaluronic acid moisturizing synergist and 1-4 parts of adhesion regulator to the hydrocolloid matrix premix and stir for 30-40 minutes at 50-60℃ and 250-300 rpm. Then cool to 35-45℃, add 3-8 parts of plant-derived healing-promoting active peptides and 0.1-0.5 parts of preservative, and continue stirring for 20-30 minutes to obtain a uniform hydrocolloid slurry.

[0014] Step 3: Degassing treatment The hydrocolloid mixture is transferred to a vacuum degassing tank and degassed for 15-25 minutes under a vacuum of 0.07-0.09 MPa and a temperature of 35-45℃ to remove air bubbles from the mixture.

[0015] Step 4: Shaping and Drying The degassed hydrocolloid mixture is evenly coated onto the release paper, with the coating thickness controlled at 0.5-1.5 mm. The coated mixture is then placed in a drying oven and dried for 2-4 hours at 50-60℃ and 30%-40% relative humidity to obtain a hydrocolloid film.

[0016] Step 5: Lamination and Cutting A medical nonwoven fabric is laminated onto one side of the hydrocolloid membrane as a backing layer, and then pressed and adhered at a pressure of 0.3-0.5 MPa, a temperature of 40-50℃, and a time of 10-20 seconds. The membrane is then cut to the preset size, packaged, and sterilized using ethylene oxide at a temperature of 30-50℃ for 2-4 hours, with a residual ethylene oxide content of ≤10 micrograms / gram, to obtain the finished antibacterial and healing-promoting hydrocolloid wound dressing.

[0017] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention exhibits excellent antibacterial properties. It employs a modified chitosan-graphene composite antibacterial agent, which enhances the antibacterial activity of chitosan through quaternization modification and then combines it with graphene. On the one hand, this enhances the water solubility and antibacterial activity of chitosan; on the other hand, it utilizes the high specific surface area and charge effect of graphene to further improve the antibacterial agent's ability to disrupt bacterial cell membranes, achieving broad-spectrum and highly efficient antibacterial activity. The inhibition rate against common pathogenic bacteria in wounds, such as Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, reaches over 99%, with no risk of drug resistance and high biosafety. 2. The present invention has a significant effect on promoting healing. The plant-derived active peptides for promoting healing are extracted from Eucommia ulmoides leaves and purified by enzymatic hydrolysis. They can specifically promote the proliferation and migration of fibroblasts and endothelial cells, accelerate the growth of granulation tissue and angiogenesis, and regulate the inflammatory response of the wound, shorten the wound healing cycle, and are especially suitable for chronic and difficult-to-heal wounds. 3. This invention has excellent moisturizing properties. The polyγ-glutamic acid grafted hyaluronic acid moisturizing synergist combines polyγ-glutamic acid and hyaluronic acid through a grafting reaction, combining the high moisturizing properties of both. It can lock in moisture for a long time for wounds, create a moist healing microenvironment, and at the same time enhance the elasticity and mechanical stability of the hydrocolloid matrix, preventing the excipients from breaking during use. Detailed Implementation

[0018] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] This invention provides an antibacterial and healing-promoting hydrocolloid wound dressing, comprising the following components in parts by weight: Hydrocolloid matrix: 30-50 parts; Modified chitosan-graphene composite antibacterial agent: 5-12 parts; Plant-derived healing-promoting active peptides: 3-8 parts; Poly-γ-glutamic acid grafted hyaluronic acid moisturizing synergist: 4-10 parts; Plasticizer: 2-6 parts; Adhesion modifier: 1-4 parts; Preservative: 0.1-0.5 parts; Deionized water: 15-30 parts.

[0020] The hydrocolloid matrix in this embodiment is a mixture of sodium carboxymethyl cellulose, gelatin, and pectin in a mass ratio of 2:1:0.5-1.5; The plasticizer is a mixture of glycerin and polyethylene glycol 400 in a mass ratio of 1:1-2; The adhesion modifier is a mixture of povidone K30 and xanthan gum in a mass ratio of 3:1; The preservative is phenoxyethanol.

[0021] The preparation method of the modified chitosan-graphene composite antibacterial agent in this embodiment is as follows: S1. Preparation of quaternized modified chitosan Add 5-8 parts of chitosan to 40-60 parts of acetic acid solution with a mass fraction of 2%-5%, and stir to dissolve at 35-45℃ and 150-200 rpm to obtain a chitosan solution. Slowly add 8-12 parts of 30% 3-chloro-2-hydroxypropyltrimethylammonium chloride solution to the chitosan solution. After the addition is complete, adjust the pH of the system to 8.0-9.0, raise the temperature to 60-70℃, and keep the reaction at this temperature for 4-6 hours. After the reaction is complete, pour the reaction solution into 100-150 parts of acetone to precipitate, filter and collect the precipitate, wash it 3-5 times with anhydrous ethanol, and then dry it in a vacuum drying oven at 60-70℃ for 8-12 hours to obtain quaternized modified chitosan. S2, Preparation of graphene oxide Using a modified Hummers method, 2-3 parts of graphite powder were added to 50-70 parts of 98% concentrated sulfuric acid, and stirred for 30-40 minutes at 0-5℃ and 80-100 rpm. 6-8 parts of potassium permanganate were slowly added, controlling the temperature to not exceed 10℃, and stirring continued for 1-2 hours. The temperature was then raised to 35-40℃ and maintained for 2-3 hours. 100-120 parts of deionized water were slowly added, and the temperature was raised to 90-95℃ and maintained for 30-40 minutes. After the reaction, 20-30 parts of 30% hydrogen peroxide solution were added, and the mixture was stirred for 10-15 minutes until the solution turned bright yellow. The reaction solution was centrifuged, the precipitate was collected, washed 2-3 times with 5% hydrochloric acid solution, then washed with deionized water until neutral, and finally dried in a vacuum drying oven at 50-60℃ for 6-8 hours to obtain graphene oxide. S3, Preparation of modified chitosan-graphene composite antibacterial agent Add 3-5 parts of quaternized modified chitosan to 30-50 parts of deionized water and stir to dissolve at 40-50℃ and 180-220 rpm to obtain a quaternized modified chitosan solution. Add 1-2 parts of graphene oxide to 20-30 parts of deionized water and ultrasonically disperse for 20-30 minutes at an ultrasonic power of 300-400 watts to obtain a graphene oxide dispersion. Slowly add the graphene oxide dispersion to the quaternized modified chitosan solution and stir to react for 2-3 hours at 50-60℃ and 200-250 rpm. After the reaction, centrifuge the reaction solution at 8000-10000 rpm for 15-20 minutes, collect the precipitate, wash it 2-3 times with deionized water, dry it in a vacuum drying oven at 60-70℃ for 8-10 hours, and pulverize it through a 100-mesh sieve to obtain a modified chitosan-graphene composite antibacterial agent.

[0022] The preparation method of the plant-derived healing-promoting active peptides in this embodiment is as follows: S1. Pretreatment of Eucommia ulmoides leaf raw materials Select dried Eucommia ulmoides leaves, pulverize them and pass them through a 60-mesh sieve. Take 5-10 parts of Eucommia ulmoides leaf powder and add it to 40-60 parts of deionized water. Stir and extract for 1-2 hours at 50-60℃ and 120-150 rpm. Filter to remove residue to obtain crude Eucommia ulmoides leaf extract. Concentrate the crude extract under reduced pressure at 40-50℃ and a vacuum of 0.06-0.08 MPa to 1 / 3-1 / 2 of the original volume to obtain concentrated Eucommia ulmoides leaf extract. S2. Enzymatic hydrolysis to prepare crude active peptides Add 0.3-0.6 parts of a complex protease, composed of papain and alkaline protease in a 1:1 mass ratio, to the concentrated Eucommia ulmoides leaf extract. Adjust the pH of the system to 6.5-7.5 and hydrolyze the enzyme at 50-60℃ and 150-180 rpm for 2-3 hours. After hydrolysis, heat to 90-95℃ and incubate for 10-15 minutes to inactivate the enzyme. After cooling to room temperature, centrifuge at 6000-8000 rpm for 10-15 minutes and collect the supernatant to obtain a crude solution of active peptides. S3. Purification yields plant-derived healing-promoting active peptides. The crude active peptide solution was initially purified by passing it through a macroporous resin adsorption column. Impurities were first eluted with deionized water, followed by elution with a 20%-30% (w / w) ethanol solution. The eluent was collected. The eluent was concentrated under reduced pressure at 35-45℃ and a vacuum of 0.06-0.08 MPa to remove ethanol. The concentrate was further purified by passing it through a gel filtration chromatography column with deionized water as the mobile phase at a flow rate of 0.5-1.0 mL / min. The eluent corresponding to the main peak was collected. The collected eluent was freeze-dried at -40 to -30℃ and a vacuum of 10-30 Pa for 24-36 hours to obtain the plant-derived healing-promoting active peptide.

[0023] The preparation method of the polyγ-glutamic acid-grafted hyaluronic acid moisturizing synergist in this embodiment is as follows: Add 2-4 parts of polyγ-glutamic acid and 3-5 parts of hyaluronic acid to 30-50 parts of deionized water and stir to dissolve at 45-55℃ and 180-220 rpm to obtain a mixed solution. Add 0.2-0.4 parts of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and 0.1-0.3 parts of N-hydroxysuccinimide to the mixed solution and adjust the pH of the system to 5.0-6.0. React at room temperature and 150-200 rpm for 3-5 hours. After the reaction, put the reaction solution into a dialysis bag with a molecular weight cutoff of 8000-14000 Daltons and dialyze with deionized water for 24-36 hours, changing the deionized water 3-4 times during the process. Freeze-dry the dialyzed solution at -40 to -30℃ and a vacuum of 10-30 Pa for 24-36 hours to obtain a polyγ-glutamic acid-grafted hyaluronic acid moisturizing synergist.

[0024] A method for preparing an antibacterial and healing-promoting hydrocolloid wound dressing includes the following steps: Step 1: Preparation of hydrocolloid matrix premix Add 30-50 parts by weight of the hydrocolloid matrix to 15-30 parts of deionized water and stir to dissolve at 60-70℃ and 200-250 rpm. Then add 2-6 parts of plasticizer and continue stirring for 20-30 minutes to obtain the hydrocolloid matrix premix.

[0025] Step 2: Add the functional ingredients and mix well. Add 5-12 parts of modified chitosan-graphene composite antibacterial agent, 4-10 parts of polyγ-glutamic acid grafted hyaluronic acid moisturizing synergist and 1-4 parts of adhesion regulator to the hydrocolloid matrix premix and stir for 30-40 minutes at 50-60℃ and 250-300 rpm. Then cool to 35-45℃, add 3-8 parts of plant-derived healing-promoting active peptides and 0.1-0.5 parts of preservative, and continue stirring for 20-30 minutes to obtain a uniform hydrocolloid slurry.

[0026] Step 3: Degassing treatment The hydrocolloid mixture is transferred to a vacuum degassing tank and degassed for 15-25 minutes under a vacuum of 0.07-0.09 MPa and a temperature of 35-45℃ to remove air bubbles from the mixture.

[0027] Step 4: Shaping and Drying The degassed hydrocolloid mixture is evenly coated onto the release paper, with the coating thickness controlled at 0.5-1.5 mm. The coated mixture is then placed in a drying oven and dried for 2-4 hours at 50-60℃ and 30%-40% relative humidity to obtain a hydrocolloid film.

[0028] Step 5: Lamination and Cutting A medical nonwoven fabric is laminated onto one side of the hydrocolloid membrane as a backing layer, and then pressed and adhered at a pressure of 0.3-0.5 MPa, a temperature of 40-50℃, and a time of 10-20 seconds. The membrane is then cut to the preset size, packaged, and sterilized using ethylene oxide at a temperature of 30-50℃ for 2-4 hours, with a residual ethylene oxide content of ≤10 micrograms / gram, to obtain the finished antibacterial and healing-promoting hydrocolloid wound dressing. Example 1:

[0029] An antibacterial and healing-promoting hydrocolloid wound dressing, comprising, by weight parts: Hydrocolloid matrix: 35 parts (sodium carboxymethyl cellulose, gelatin, and pectin mixed in a mass ratio of 2:1:1); Modified chitosan-graphene composite antibacterial agent: 8 parts; Plant-derived healing-promoting active peptides: 5 parts; Poly-γ-glutamic acid grafted hyaluronic acid moisturizing synergist: 7 parts; Plasticizer: 4 parts (glycerin and polyethylene glycol 400 mixed at a mass ratio of 1:1.5); Adhesion modifier: 2 parts (povidone K30 and xanthan gum mixed at a mass ratio of 3:1); Preservative: 0.3 parts (phenoxyethanol); 22 portions of deionized water.

[0030] Preparation of modified chitosan-graphene composite antibacterial agent: S1. Preparation of quaternized modified chitosan Six parts of chitosan were added to 50 parts of a 3% acetic acid solution and stirred at 40°C and 180 rpm to dissolve, thus obtaining a chitosan solution. Ten parts of a 30% 3-chloro-2-hydroxypropyltrimethylammonium chloride solution were slowly added dropwise to the chitosan solution. After the addition was complete, the pH of the system was adjusted to 8.5, the temperature was raised to 65°C, and the reaction was maintained for 5 hours. After the reaction was completed, the reaction solution was poured into 120 parts of acetone to precipitate the precipitate. The precipitate was collected by filtration, washed four times with anhydrous ethanol, and then dried in a vacuum drying oven at 65°C for 10 hours to obtain quaternized modified chitosan. S2, Preparation of graphene oxide Using a modified Hummers method, 2.5 parts of graphite powder were added to 60 parts of 98% concentrated sulfuric acid and stirred for 35 minutes at 3°C ​​and 90 rpm. Then, 7 parts of potassium permanganate were slowly added, with the temperature controlled below 10°C, and stirring continued for 1.5 hours. The temperature was then raised to 38°C and maintained for 2.5 hours. Next, 110 parts of deionized water were slowly added, and the temperature was raised to 93°C and maintained for 35 minutes. After the reaction was complete, 25 parts of 30% hydrogen peroxide solution were added and stirred for 12 minutes. The reaction mixture was centrifuged, the precipitate was collected, washed three times with 5% hydrochloric acid solution, then washed with deionized water until neutral, and finally dried in a vacuum oven at 55°C for 7 hours to obtain graphene oxide. S3, Preparation of modified chitosan-graphene composite antibacterial agent Four parts of quaternized modified chitosan were added to 40 parts of deionized water and stirred at 45°C and 200 rpm to dissolve. 1.5 parts of graphene oxide were added to 25 parts of deionized water and ultrasonically dispersed for 25 minutes (ultrasonic power 350 W) to obtain a graphene oxide dispersion. The graphene oxide dispersion was slowly added to the quaternized modified chitosan solution and stirred at 55°C and 220 rpm for 2.5 hours. After the reaction, the reaction solution was centrifuged (9000 rpm, 18 minutes), the precipitate was collected, washed three times with deionized water, dried in a vacuum drying oven at 65°C for 9 hours, and pulverized through a 100-mesh sieve to obtain the modified chitosan-graphene composite antibacterial agent.

[0031] Preparation of plant-derived healing-promoting active peptides: S1. Pretreatment of Eucommia ulmoides leaf raw materials Select dried Eucommia ulmoides leaves, pulverize them and pass them through a 60-mesh sieve. Take 7 parts of Eucommia ulmoides leaf powder and add it to 50 parts of deionized water. Stir and extract for 1.5 hours at 55℃ and 130 rpm. Filter to remove residue and obtain crude Eucommia ulmoides leaf extract. Concentrate the crude extract under reduced pressure at 45℃ and 0.07 MPa to 1 / 2 of the original volume to obtain Eucommia ulmoides leaf concentrate. S2. Enzymatic hydrolysis to prepare crude active peptides Add 0.4 parts of a complex protease (papain and alkaline protease in a 1:1 mass ratio) to the concentrated Eucommia ulmoides leaf extract, adjust the pH of the system to 7.0, and enzymatically hydrolyze for 2.5 hours at 55℃ and 160 rpm. After enzymatic hydrolysis, heat to 93℃ and incubate for 12 minutes to inactivate the enzyme. After cooling to room temperature, centrifuge (7000 rpm for 12 minutes) and collect the supernatant to obtain a crude solution of active peptides. S3. Purification yields plant-derived healing-promoting active peptides. The crude active peptide solution was passed through a macroporous resin adsorption column (model D101). Impurities were first eluted with deionized water, followed by elution with a 25% (w / w) ethanol solution. The eluent was collected. The eluent was concentrated under reduced pressure at 40°C and 0.07 MPa to remove ethanol. The concentrated solution was then passed through a gel filtration chromatography column (model Sephadex G-25) with deionized water as the mobile phase at a flow rate of 0.8 mL / min. The eluent corresponding to the main peak was collected. The collected eluent was freeze-dried (freezing temperature -35°C, vacuum 20 Pa, drying time 30 hours) to obtain the plant-derived healing-promoting active peptide.

[0032] Preparation of poly-γ-glutamic acid-grafted hyaluronic acid moisturizing synergist: Three parts of poly-γ-glutamic acid and four parts of hyaluronic acid were added to 40 parts of deionized water and stirred at 50°C and 200 rpm to dissolve. 0.3 parts of EDC and 0.2 parts of NHS were added to the mixed solution to adjust the pH to 5.5. The mixture was reacted at room temperature and 180 rpm for 4 hours. After the reaction, the reaction solution was placed in a dialysis bag (molecular weight cutoff 8000-14000 Daltons) and dialyzed with deionized water for 30 hours, changing the deionized water three times during this period. The dialyzed solution was freeze-dried (freezing temperature -35°C, vacuum degree 20 Pa, drying time 30 hours) to obtain a poly-γ-glutamic acid-grafted hyaluronic acid moisturizing synergist.

[0033] Preparation of hydrocolloid wound dressings: Step 1: Preparation of hydrocolloid matrix premix 35 parts of hydrocolloid matrix were added to 22 parts of deionized water and stirred at 65°C and 220 rpm to dissolve. Then 4 parts of plasticizer were added and stirring was continued for 25 minutes to obtain the hydrocolloid matrix premix. Step 2: Add the functional ingredients and mix well. Eight parts of modified chitosan-graphene composite antibacterial agent, seven parts of polyγ-glutamic acid grafted hyaluronic acid moisturizing synergist and two parts of adhesion regulator were added to the hydrocolloid matrix premix and stirred for 35 minutes at 55°C and 280 rpm. Then the temperature was lowered to 40°C, five parts of plant-derived healing-promoting active peptides and 0.3 parts of preservative were added, and stirring was continued for 25 minutes to obtain a uniform hydrocolloid mixture. Step 3: Degassing treatment The hydrocolloid mixture was transferred to a vacuum degassing tank and degassed for 20 minutes under a vacuum of 0.08 MPa and a temperature of 40°C. Step 4: Shaping and Drying The degassed hydrocolloid mixture was evenly coated onto the release paper, with the coating thickness controlled at 1.0 mm. The coated mixture was then placed in a drying oven and dried for 3 hours at 55°C and 35% relative humidity to obtain a hydrocolloid film. Step 5: Lamination and Cutting A medical nonwoven fabric is laminated to one side of the hydrocolloid membrane as a backing layer and then pressed and bonded (pressure 0.4 MPa, temperature 45℃, time 15 seconds); then it is cut according to the preset size, packaged and sterilized with ethylene oxide (sterilization temperature 40℃, sterilization time 3 hours, ethylene oxide residue ≤10 micrograms / gram) to obtain the finished antibacterial and healing-promoting hydrocolloid wound dressing. Example 2

[0034] An antibacterial and healing-promoting hydrocolloid wound dressing, comprising, by weight parts: Hydrocolloid matrix: 30 parts (sodium carboxymethyl cellulose, gelatin, and pectin mixed in a mass ratio of 2:1:0.5); Modified chitosan-graphene composite antibacterial agent: 5 parts; Plant-derived healing-promoting active peptides: 3 portions; Poly-γ-glutamic acid grafted hyaluronic acid moisturizing synergist: 4 parts; Plasticizer: 2 parts (glycerin and polyethylene glycol 400 mixed in a 1:1 mass ratio); Adhesion modifier: 1 part (povidone K30 and xanthan gum mixed at a mass ratio of 3:1); Preservative: 0.1 parts (phenoxyethanol); Deionized water: 15 parts.

[0035] Preparation of modified chitosan-graphene composite antibacterial agent: S1. Preparation of quaternized modified chitosan Five parts of chitosan were added to 40 parts of a 2% acetic acid solution and stirred at 35°C and 150 rpm to dissolve, thus obtaining a chitosan solution. Eight parts of a 30% 3-chloro-2-hydroxypropyltrimethylammonium chloride solution were slowly added dropwise to the chitosan solution. After the addition was complete, the pH of the system was adjusted to 8.0, the temperature was raised to 60°C, and the reaction was maintained for 4 hours. After the reaction was completed, the reaction solution was poured into 100 parts of acetone to precipitate the precipitate. The precipitate was collected by filtration, washed three times with anhydrous ethanol, and then dried in a vacuum drying oven at 60°C for 8 hours to obtain quaternized modified chitosan. S2, Preparation of graphene oxide Using a modified Hummers method, 2 parts of graphite powder were added to 50 parts of 98% concentrated sulfuric acid and stirred for 30 minutes at 0°C and 80 rpm. 6 parts of potassium permanganate were slowly added, with the temperature controlled below 10°C, and stirring continued for 1 hour. The temperature was then raised to 35°C and maintained for 2 hours. 100 parts of deionized water were slowly added, and the temperature was raised to 90°C and maintained for 30 minutes. After the reaction was complete, 20 parts of 30% hydrogen peroxide solution were added and stirred for 10 minutes. The reaction solution was centrifuged, the precipitate was collected, washed twice with 5% hydrochloric acid solution, then washed with deionized water until neutral, and finally dried in a vacuum oven at 50°C for 6 hours to obtain graphene oxide. S3, Preparation of modified chitosan-graphene composite antibacterial agent Three parts of quaternized modified chitosan were added to 30 parts of deionized water and stirred at 40°C and 180 rpm to dissolve. One part of graphene oxide was added to 20 parts of deionized water and ultrasonically dispersed for 20 minutes (ultrasonic power 300 W) to obtain a graphene oxide dispersion. The graphene oxide dispersion was slowly added to the quaternized modified chitosan solution and stirred at 50°C and 200 rpm for 2 hours. After the reaction was completed, the reaction solution was centrifuged (8000 rpm for 15 minutes), the precipitate was collected, washed twice with deionized water, dried in a vacuum drying oven at 60°C for 8 hours, and pulverized through a 100-mesh sieve to obtain the modified chitosan-graphene composite antibacterial agent.

[0036] Preparation of plant-derived healing-promoting active peptides: S1. Pretreatment of Eucommia ulmoides leaf raw materials Select dried Eucommia ulmoides leaves, pulverize them and pass them through a 60-mesh sieve. Take 5 parts of Eucommia ulmoides leaf powder and add it to 40 parts of deionized water. Stir and extract for 1 hour at 50℃ and 120 rpm. Filter to remove residue and obtain crude Eucommia ulmoides leaf extract. Concentrate the crude extract under reduced pressure at 40℃ and 0.06 MPa to 1 / 3 of the original volume to obtain Eucommia ulmoides leaf concentrate. S2. Enzymatic hydrolysis to prepare crude active peptides Add 0.3 parts of a complex protease (papain and alkaline protease in a 1:1 mass ratio) to the concentrated Eucommia ulmoides leaf extract, adjust the pH of the system to 6.5, and enzymatically hydrolyze for 2 hours at 50℃ and 150 rpm. After enzymatic hydrolysis, heat to 90℃ and incubate for 10 minutes to inactivate the enzyme. After cooling to room temperature, centrifuge (6000 rpm for 10 minutes) and collect the supernatant to obtain a crude solution of active peptides. S3. Purification yields plant-derived healing-promoting active peptides. The crude active peptide solution was passed through a macroporous resin adsorption column (model D101). Impurities were first eluted with deionized water, followed by elution with a 20% (w / w) ethanol solution. The eluent was collected. The eluent was concentrated under reduced pressure at 35°C and 0.06 MPa to remove ethanol. The concentrated solution was then passed through a gel filtration chromatography column (model Sephadex G-25) with deionized water as the mobile phase at a flow rate of 0.5 mL / min. The eluent corresponding to the main peak was collected. The collected eluent was freeze-dried (freezing temperature -40°C, vacuum 10 Pa, drying time 24 hours) to obtain the plant-derived healing-promoting active peptide.

[0037] Preparation of poly-γ-glutamic acid-grafted hyaluronic acid moisturizing synergist: Two parts of poly-γ-glutamic acid and three parts of hyaluronic acid were added to 30 parts of deionized water and stirred at 45°C and 180 rpm to dissolve. 0.2 parts of EDC and 0.1 parts of NHS were added to the mixed solution to adjust the pH to 5.0. The mixture was reacted at room temperature and 150 rpm for 3 hours. After the reaction, the reaction solution was placed in a dialysis bag (molecular weight cutoff 8000-14000 Daltons) and dialyzed with deionized water for 24 hours, changing the deionized water three times during this period. The dialyzed solution was freeze-dried (freezing temperature -40°C, vacuum degree 10 Pa, drying time 24 hours) to obtain the poly-γ-glutamic acid-grafted hyaluronic acid moisturizing synergist.

[0038] Preparation of hydrocolloid wound dressings: Step 1: Preparation of hydrocolloid matrix premix Add 30 parts of hydrocolloid matrix to 15 parts of deionized water and stir to dissolve at 60°C and 200 rpm. Then add 2 parts of plasticizer and continue stirring for 20 minutes to obtain the hydrocolloid matrix premix. Step 2: Add the functional ingredients and mix well. Five parts of modified chitosan-graphene composite antibacterial agent, four parts of polyγ-glutamic acid grafted hyaluronic acid moisturizing synergist and one part of adhesion regulator were added to the hydrocolloid matrix premix and stirred for 30 minutes at 50°C and 250 rpm. Then the temperature was lowered to 35°C, three parts of plant-derived healing-promoting active peptides and 0.1 parts of preservative were added, and stirring was continued for 20 minutes to obtain a uniform hydrocolloid mixture. Step 3: Degassing treatment The hydrocolloid mixture was transferred to a vacuum degassing tank and degassed for 15 minutes under a vacuum of 0.07 MPa and a temperature of 35°C. Step 4: Shaping and Drying The degassed hydrocolloid mixture was evenly coated onto the release paper, with the coating thickness controlled at 0.5 mm. The coated mixture was then placed in a drying oven and dried for 2 hours at 50°C and 30% relative humidity to obtain a hydrocolloid film. Step 5: Lamination and Cutting A medical nonwoven fabric is laminated to one side of the hydrocolloid membrane as a backing layer and then pressed and bonded (pressure 0.3 MPa, temperature 40℃, time 10 seconds); then it is cut to the preset size, packaged and sterilized with ethylene oxide (sterilization temperature 30℃, sterilization time 2 hours, ethylene oxide residue ≤10 micrograms / gram) to obtain the finished antibacterial and healing-promoting hydrocolloid wound dressing. Example 3

[0039] An antibacterial and healing-promoting hydrocolloid wound dressing, comprising, by weight parts: Hydrocolloid matrix: 50 parts (sodium carboxymethyl cellulose, gelatin, and pectin mixed in a mass ratio of 2:1:1.5); Modified chitosan-graphene composite antibacterial agent: 12 parts; Plant-derived healing-promoting active peptides: 8 parts; Polyγ-glutamic acid-grafted hyaluronic acid moisturizing synergist: 10 parts; Plasticizer: 6 parts (glycerin and polyethylene glycol 400 mixed at a mass ratio of 1:2); Adhesion modifier: 4 parts (povidone K30 and xanthan gum mixed at a mass ratio of 3:1); Preservative: 0.5 parts (phenoxyethanol); Deionized water: 30 parts.

[0040] Preparation of modified chitosan-graphene composite antibacterial agent: S1. Preparation of quaternized modified chitosan Eight parts of chitosan were added to 60 parts of a 5% acetic acid solution and stirred at 45°C and 200 rpm to dissolve, thus obtaining a chitosan solution. Twelve parts of a 30% 3-chloro-2-hydroxypropyltrimethylammonium chloride solution were slowly added dropwise to the chitosan solution. After the addition was complete, the pH of the system was adjusted to 9.0, the temperature was raised to 70°C, and the reaction was maintained for 6 hours. After the reaction was completed, the reaction solution was poured into 150 parts of acetone to precipitate the precipitate. The precipitate was collected by filtration, washed five times with anhydrous ethanol, and then dried in a vacuum drying oven at 70°C for 12 hours to obtain quaternized modified chitosan. S2, Preparation of graphene oxide Using a modified Hummers method, 3 parts of graphite powder were added to 70 parts of 98% concentrated sulfuric acid and stirred for 40 minutes at 5°C and 100 rpm. 8 parts of potassium permanganate were slowly added, with the temperature controlled below 10°C, and stirring continued for 2 hours. The temperature was then raised to 40°C and maintained for 3 hours. 120 parts of deionized water were slowly added, and the temperature was raised to 95°C and maintained for 40 minutes. After the reaction was complete, 30 parts of 30% hydrogen peroxide solution were added and stirred for 15 minutes. The reaction solution was centrifuged, the precipitate was collected, washed three times with 5% hydrochloric acid solution, then washed with deionized water until neutral, and finally dried in a vacuum oven at 60°C for 8 hours to obtain graphene oxide. S3, Preparation of modified chitosan-graphene composite antibacterial agent Five parts of quaternized modified chitosan were added to 50 parts of deionized water and stirred at 50°C and 220 rpm to dissolve. Two parts of graphene oxide were added to 30 parts of deionized water and ultrasonically dispersed for 30 minutes (ultrasonic power 400 W) to obtain a graphene oxide dispersion. The graphene oxide dispersion was slowly added to the quaternized modified chitosan solution and stirred at 60°C and 250 rpm for 3 hours. After the reaction was completed, the reaction solution was centrifuged (10,000 rpm for 20 minutes), the precipitate was collected, washed three times with deionized water, dried in a vacuum drying oven at 70°C for 10 hours, and pulverized through a 100-mesh sieve to obtain the modified chitosan-graphene composite antibacterial agent.

[0041] Preparation of plant-derived healing-promoting active peptides: S1. Pretreatment of Eucommia ulmoides leaf raw materials Select dried Eucommia ulmoides leaves, pulverize them and pass them through a 60-mesh sieve. Take 10 parts of Eucommia ulmoides leaf powder and add it to 60 parts of deionized water. Stir and extract for 2 hours at 60℃ and 150 rpm. Filter to remove residue and obtain crude Eucommia ulmoides leaf extract. Concentrate the crude extract under reduced pressure at 50℃ and 0.08 MPa to 1 / 2 of the original volume to obtain Eucommia ulmoides leaf concentrate. S2. Enzymatic hydrolysis to prepare crude active peptides Add 0.6 parts of a complex protease (papain and alkaline protease in a 1:1 mass ratio) to the concentrated Eucommia ulmoides leaf extract, adjust the pH of the system to 7.5, and enzymatically hydrolyze for 3 hours at 60℃ and 180 rpm. After enzymatic hydrolysis, heat to 95℃ and incubate for 15 minutes to inactivate the enzyme. After cooling to room temperature, centrifuge (8000 rpm for 15 minutes) and collect the supernatant to obtain a crude solution of active peptides. S3. Purification yields plant-derived healing-promoting active peptides. The crude active peptide solution was passed through a macroporous resin adsorption column (model D101). Impurities were first eluted with deionized water, followed by elution with a 30% (w / w) ethanol solution. The eluent was collected. The eluent was concentrated under reduced pressure at 45°C and 0.08 MPa to remove ethanol. The concentrated solution was then passed through a gel filtration chromatography column (model Sephadex G-25) with deionized water as the mobile phase at a flow rate of 1.0 mL / min. The eluent corresponding to the main peak was collected. The collected eluent was freeze-dried (freezing temperature -30°C, vacuum 30 Pa, drying time 36 hours) to obtain the plant-derived healing-promoting active peptide.

[0042] Preparation of poly-γ-glutamic acid-grafted hyaluronic acid moisturizing synergist: Four parts of poly-γ-glutamic acid and five parts of hyaluronic acid were added to 50 parts of deionized water and stirred at 55°C and 220 rpm to dissolve. 0.4 parts of EDC and 0.3 parts of NHS were added to the mixed solution to adjust the pH to 6.0. The mixture was reacted at room temperature and 200 rpm for 5 hours. After the reaction, the reaction solution was placed in a dialysis bag (molecular weight cutoff 8000-14000 Daltons) and dialyzed with deionized water for 36 hours, changing the deionized water four times during this period. The dialyzed solution was freeze-dried (freezing temperature -30°C, vacuum degree 30 Pa, drying time 36 hours) to obtain a poly-γ-glutamic acid-grafted hyaluronic acid moisturizing synergist.

[0043] Preparation of hydrocolloid wound dressings: Step 1: Preparation of hydrocolloid matrix premix Add 50 parts of hydrocolloid matrix to 30 parts of deionized water and stir to dissolve at 70°C and 250 rpm. Then add 6 parts of plasticizer and continue stirring for 30 minutes to obtain the hydrocolloid matrix premix. Step 2: Add the functional ingredients and mix well. Twelve parts of modified chitosan-graphene composite antibacterial agent, ten parts of polyγ-glutamic acid grafted hyaluronic acid moisturizing synergist, and four parts of adhesion regulator were added to the hydrocolloid matrix premix and stirred for 40 minutes at 60°C and 300 rpm. Then, the temperature was lowered to 45°C, eight parts of plant-derived healing-promoting active peptides and 0.5 parts of preservative were added, and stirring was continued for 30 minutes to obtain a uniform hydrocolloid slurry. Step 3: Degassing treatment The hydrocolloid mixture was transferred to a vacuum degassing tank and degassed for 25 minutes under a vacuum of 0.09 MPa and a temperature of 45°C. Step 4: Shaping and Drying The degassed hydrocolloid mixture was evenly coated onto the release paper, with the coating thickness controlled at 1.5 mm. The coated mixture was then placed in a drying oven and dried for 4 hours at 60°C and 40% relative humidity to obtain a hydrocolloid film. Step 5: Lamination and Cutting A medical nonwoven fabric is laminated to one side of the hydrocolloid membrane as a backing layer and then pressed and bonded (pressure 0.5 MPa, temperature 50℃, time 20 seconds); then it is cut to the preset size, packaged and sterilized with ethylene oxide (sterilization temperature 50℃, sterilization time 4 hours, ethylene oxide residue ≤10 micrograms / gram) to obtain the finished antibacterial and healing-promoting hydrocolloid wound dressing.

[0044] Performance testing The antibacterial and healing-promoting hydrocolloid wound dressings prepared in Examples 1, 2, and 3 were subjected to performance tests under the same conditions. The test methods and results are as follows:

[0045] I. Testing Methods 1. Antibacterial properties: The inhibition zone method was used, with Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC25922), and Pseudomonas aeruginosa (ATCC 27853) as test strains. After 24 hours of incubation, the diameter of the inhibition zone was measured and the inhibition rate was calculated. 2. Promoting healing performance: A full-thickness skin trauma model of rat back was established, with 10 rats in each group. The wound healing was observed daily, and the time to complete healing was recorded. After healing, the thickness of granulation tissue and the number of new blood vessels were measured. 3. Moisturizing performance: The sample was placed in an environment with a relative humidity of 30% and a temperature of 25°C. After 24 hours, the moisture content of the sample was determined by gravimetric method. 4. Adhesion performance: The adhesion strength between the sample and pigskin was determined using a universal testing machine, and the adhesion of the wound surface during replacement was observed; 5. Biocompatibility: Skin irritation test (closed patch for 48 hours) and acute toxicity test (transdermal administration) were conducted in accordance with the GB / T 16886 series of standards to evaluate biocompatibility.

[0046] II. Test Results 1. Test results of Example 1:

[0047] (1) Antibacterial properties: The diameters of the inhibition zones against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were 22.5 mm, 21.3 mm, and 20.8 mm, respectively, with inhibition rates of ≥99% for all three bacteria; (2) Healing promotion performance: The wound healing time was 12 days, which was 33.3% shorter than the blank control group (18 days). After the wound healed, the granulation tissue grew evenly, and the number of new blood vessels increased by 45% compared with the control group. (3) Moisturizing performance: The water content was 48.2% after 24 hours; (4) Adhesion performance: The adhesion strength is 0.25 N / cm, and there is no adhesion phenomenon on the wound surface during replacement; (5) Biosafety: No skin irritation, no acute toxicity, and good biocompatibility. 2. Test results of Example 2:

[0048] (1) Antibacterial properties: The diameters of the inhibition zones against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were 19.2 mm, 18.5 mm, and 17.8 mm, respectively, with inhibition rates of ≥98% for all three bacteria; (2) Healing promotion performance: The wound healing time was 14 days, which was 22.2% shorter than that of the blank control group. After the wound healed, the growth of granulation tissue was more uniform, and the number of new blood vessels increased by 32% compared with the control group. (3) Moisturizing performance: The water content was 45.3% after 24 hours; (4) Adhesion performance: The adhesion strength is 0.22 N / cm, and there is no adhesion phenomenon on the wound surface during replacement; (5) Biosafety: No skin irritation, no acute toxicity, and good biocompatibility. 3. Test results of Example 3:

[0049] (1) Antibacterial properties: The diameters of the inhibition zones against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were 25.1 mm, 24.3 mm, and 23.6 mm, respectively, with inhibition rates ≥99.5% for all three bacteria; (2) Healing promotion performance: The wound healing time was 10 days, which was 44.4% shorter than the blank control group. After the wound healed, the granulation tissue was thick and uniform, and the number of new blood vessels increased by 62% compared with the control group. (3) Moisturizing performance: The water content was 52.6% after 24 hours; (4) Adhesion performance: The adhesion strength is 0.28 N / cm, and there is no adhesion phenomenon on the wound surface during replacement; (5) Biosafety: No skin irritation, no acute toxicity, and good biocompatibility.

[0050] III. Results Analysis Test results show that the antibacterial and healing-promoting hydrocolloid wound dressings prepared in Examples 1, 2, and 3 all possess excellent antibacterial properties, significant healing-promoting effects, and good usability, meeting the requirements for medical wound dressings. Among them, Example 3 exhibits the best antibacterial, healing-promoting, and moisturizing properties due to its higher levels of antibacterial agents and healing-promoting active peptides; although Example 2 has the lowest levels of each functional component, its performance still meets basic clinical needs, and the appropriate formulation can be selected according to the actual application scenario.

[0051] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0052] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An antibacterial and healing-promoting hydrocolloid wound dressing, characterized in that, The ingredients include the following parts by weight: Hydrocolloid matrix: 30-50 parts; Modified chitosan-graphene composite antibacterial agent: 5-12 parts; Plant-derived healing-promoting active peptides: 3-8 parts; Poly-γ-glutamic acid grafted hyaluronic acid moisturizing synergist: 4-10 parts; Plasticizer: 2-6 parts; Adhesion modifier: 1-4 parts; Preservative: 0.1-0.5 parts; Deionized water: 15-30 parts.

2. The antibacterial and healing-promoting hydrocolloid wound dressing according to claim 1, characterized in that, The hydrocolloid matrix is ​​a mixture of sodium carboxymethyl cellulose, gelatin, and pectin in a mass ratio of 2:1:0.5-1.5; The plasticizer is a mixture of glycerin and polyethylene glycol 400 in a mass ratio of 1:1-2; The adhesion modifier is a mixture of povidone K30 and xanthan gum in a mass ratio of 3:1; The preservative is phenoxyethanol.

3. The antibacterial and healing-promoting hydrocolloid wound dressing according to claim 1, characterized in that, The preparation method of the modified chitosan-graphene composite antibacterial agent is as follows: S1. Preparation of quaternized modified chitosan Add 5-8 parts of chitosan to 40-60 parts of acetic acid solution with a mass fraction of 2%-5%, and stir to dissolve at 35-45℃ and 150-200 rpm to obtain a chitosan solution. Slowly add 8-12 parts of 30% 3-chloro-2-hydroxypropyltrimethylammonium chloride solution to the chitosan solution. After the addition is complete, adjust the pH of the system to 8.0-9.0, raise the temperature to 60-70℃, and keep the reaction at this temperature for 4-6 hours. After the reaction is complete, pour the reaction solution into 100-150 parts of acetone to precipitate, filter and collect the precipitate, wash it 3-5 times with anhydrous ethanol, and then dry it in a vacuum drying oven at 60-70℃ for 8-12 hours to obtain quaternized modified chitosan. S2, Preparation of graphene oxide Using a modified Hummers method, 2-3 parts of graphite powder were added to 50-70 parts of 98% concentrated sulfuric acid, and stirred for 30-40 minutes at 0-5℃ and 80-100 rpm. 6-8 parts of potassium permanganate were slowly added, controlling the temperature to not exceed 10℃, and stirring continued for 1-2 hours. The temperature was then raised to 35-40℃ and maintained for 2-3 hours. 100-120 parts of deionized water were slowly added, and the temperature was raised to 90-95℃ and maintained for 30-40 minutes. After the reaction, 20-30 parts of 30% hydrogen peroxide solution were added, and the mixture was stirred for 10-15 minutes until the solution turned bright yellow. The reaction solution was centrifuged, the precipitate was collected, washed 2-3 times with 5% hydrochloric acid solution, then washed with deionized water until neutral, and finally dried in a vacuum drying oven at 50-60℃ for 6-8 hours to obtain graphene oxide. S3, Preparation of modified chitosan-graphene composite antibacterial agent Add 3-5 parts of quaternized modified chitosan to 30-50 parts of deionized water and stir to dissolve at 40-50℃ and 180-220 rpm to obtain a quaternized modified chitosan solution. Add 1-2 parts of graphene oxide to 20-30 parts of deionized water and ultrasonically disperse for 20-30 minutes at an ultrasonic power of 300-400 watts to obtain a graphene oxide dispersion. Slowly add the graphene oxide dispersion to the quaternized modified chitosan solution and stir to react for 2-3 hours at 50-60℃ and 200-250 rpm. After the reaction, centrifuge the reaction solution at 8000-10000 rpm for 15-20 minutes, collect the precipitate, wash it 2-3 times with deionized water, dry it in a vacuum drying oven at 60-70℃ for 8-10 hours, and pulverize it through a 100-mesh sieve to obtain a modified chitosan-graphene composite antibacterial agent.

4. The antibacterial and healing-promoting hydrocolloid wound dressing according to claim 1, characterized in that, The preparation method of the plant-derived healing-promoting active peptide is as follows: S1. Pretreatment of Eucommia ulmoides leaf raw materials Select dried Eucommia ulmoides leaves, pulverize them and pass them through a 60-mesh sieve. Take 5-10 parts of Eucommia ulmoides leaf powder and add it to 40-60 parts of deionized water. Stir and extract for 1-2 hours at 50-60℃ and 120-150 rpm. Filter to remove residue to obtain crude Eucommia ulmoides leaf extract. Concentrate the crude extract under reduced pressure at 40-50℃ and a vacuum of 0.06-0.08 MPa to 1 / 3-1 / 2 of the original volume to obtain concentrated Eucommia ulmoides leaf extract. S2. Enzymatic hydrolysis to prepare crude active peptides Add 0.3-0.6 parts of a complex protease, composed of papain and alkaline protease in a 1:1 mass ratio, to the concentrated Eucommia ulmoides leaf extract. Adjust the pH of the system to 6.5-7.5 and hydrolyze the enzyme at 50-60℃ and 150-180 rpm for 2-3 hours. After hydrolysis, heat to 90-95℃ and incubate for 10-15 minutes to inactivate the enzyme. After cooling to room temperature, centrifuge at 6000-8000 rpm for 10-15 minutes and collect the supernatant to obtain a crude solution of active peptides. S3. Purification yields plant-derived healing-promoting active peptides. The crude active peptide solution was initially purified by passing it through a macroporous resin adsorption column. Impurities were first eluted with deionized water, followed by elution with a 20%-30% (w / w) ethanol solution. The eluent was collected. The eluent was concentrated under reduced pressure at 35-45℃ and a vacuum of 0.06-0.08 MPa to remove ethanol. The concentrate was further purified by passing it through a gel filtration chromatography column with deionized water as the mobile phase at a flow rate of 0.5-1.0 mL / min. The eluent corresponding to the main peak was collected. The collected eluent was freeze-dried at -40 to -30℃ and a vacuum of 10-30 Pa for 24-36 hours to obtain the plant-derived healing-promoting active peptide.

5. The antibacterial and healing-promoting hydrocolloid wound dressing according to claim 1, characterized in that, The preparation method of the polyγ-glutamic acid-grafted hyaluronic acid moisturizing synergist is as follows: Add 2-4 parts of polyγ-glutamic acid and 3-5 parts of hyaluronic acid to 30-50 parts of deionized water and stir to dissolve at 45-55℃ and 180-220 rpm to obtain a mixed solution. Add 0.2-0.4 parts of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and 0.1-0.3 parts of N-hydroxysuccinimide to the mixed solution and adjust the pH of the system to 5.0-6.

0. React at room temperature and 150-200 rpm for 3-5 hours. After the reaction, put the reaction solution into a dialysis bag with a molecular weight cutoff of 8000-14000 Daltons and dialyze with deionized water for 24-36 hours, changing the deionized water 3-4 times during the process. Freeze-dry the dialyzed solution at -40 to -30℃ and a vacuum of 10-30 Pa for 24-36 hours to obtain a polyγ-glutamic acid-grafted hyaluronic acid moisturizing synergist.

6. A method for preparing an antibacterial and healing-promoting hydrocolloid wound dressing, characterized in that, Includes the following steps: Step 1: Preparation of hydrocolloid matrix premix Add 30-50 parts by weight of the hydrocolloid matrix to 15-30 parts of deionized water and stir to dissolve at 60-70℃ and 200-250 rpm. Then add 2-6 parts of plasticizer and continue stirring for 20-30 minutes to obtain the hydrocolloid matrix premix. Step 2: Add the functional ingredients and mix well. Add 5-12 parts of modified chitosan-graphene composite antibacterial agent, 4-10 parts of polyγ-glutamic acid grafted hyaluronic acid moisturizing synergist and 1-4 parts of adhesion regulator to the hydrocolloid matrix premix and stir for 30-40 minutes at 50-60℃ and 250-300 rpm. Then cool to 35-45℃, add 3-8 parts of plant-derived healing-promoting active peptides and 0.1-0.5 parts of preservative, and continue stirring for 20-30 minutes to obtain a uniform hydrocolloid slurry. Step 3: Degassing treatment The hydrocolloid mixture is transferred to a vacuum degassing tank and degassed for 15-25 minutes under a vacuum of 0.07-0.09 MPa and a temperature of 35-45℃ to remove air bubbles from the mixture. Step 4: Shaping and Drying The degassed hydrocolloid mixture is evenly coated onto the release paper, with the coating thickness controlled at 0.5-1.5 mm. The coated mixture is then placed in a drying oven and dried for 2-4 hours at 50-60℃ and 30%-40% relative humidity to obtain a hydrocolloid film. Step 5: Lamination and Cutting A medical nonwoven fabric is laminated onto one side of the hydrocolloid membrane as a backing layer, and then pressed and adhered at a pressure of 0.3-0.5 MPa, a temperature of 40-50℃, and a time of 10-20 seconds. The membrane is then cut to the preset size, packaged, and sterilized using ethylene oxide at a temperature of 30-50℃ for 2-4 hours, with a residual ethylene oxide content of ≤10 micrograms / gram, to obtain the finished antibacterial and healing-promoting hydrocolloid wound dressing.