A hydrogel wound dressing and its preparation method

Abstract

This application provides a hydrogel wound dressing and its preparation method, comprising: a hydrogel layer, a support layer, and a protective layer. The hydrogel layer is prepared from the following raw material components in the following mass ratio: 10-15% polyvinylpyrrolidone, 5-8% polycaprolactone, 2-4% sodium carboxymethyl cellulose, 1-3% chitosan, 0.5-1.5% antibacterial agent, 0.1-0.3% antioxidant, 0.01-0.1% growth factor, 0.1-0.5% thermosensitive polymer, 0.05-0.15% graphene quantum dots, 0.5-1.5% self-healing polymer, 0.5-1.5% pH-sensitive material, 0.1-0.3% nano-titanium dioxide, and the balance being deionized water. The support layer is a porous polylactic acid film with a thickness of 0.1-0.3 mm. The protective layer is a breathable polyurethane film with a thickness of 0.2-0.4 mm. Through the synergistic effect of the antibacterial agent, nano-titanium dioxide, and graphene quantum dots, the antibacterial performance of the dressing is significantly improved.

Description

TECHNICAL FIELD

[0001] The embodiment of the present application relates to the technical field of medical dressings, in particular to a hydrogel wound dressing and a preparation method thereof. BACKGROUND

[0002] With the continuous progress of medical technology, the demand for wound care is also increasing. Modern wound care not only needs to provide basic protection function, but also needs to have antibacterial, promote healing, reduce scar and other functions. Especially in the treatment of complex wounds (such as diabetic ulcers, burns, surgical incisions, etc.), the requirements for dressings are higher.

[0003] The common wound dressings on the market at present mainly include traditional gauze, biological dressing and hydrogel dressing, etc., but the above-mentioned wound dressings have the following main defects:

[0004] Insufficient antibacterial performance: most of the traditional dressings and part of the hydrogel dressings lack long-acting antibacterial performance, which is easy to cause wound infection.

[0005] Poor self-healing ability: the existing hydrogel dressing cannot quickly recover the integrity after physical damage, which affects its use effect and service life.

[0006] Poor environmental responsiveness: the existing dressing cannot adjust its own properties according to the change of wound environment (such as pH value change), and it is difficult to provide personalized care.

[0007] Insufficient comprehensive performance: the dressing of single component is difficult to have multiple functions such as moisturizing, air permeability, antibacterial, self-healing and environmental responsiveness, and multiple components are needed to realize comprehensive care effect. SUMMARY

[0008] The embodiment of the present application provides a hydrogel wound dressing and a preparation method thereof, to solve the problem of poor antibacterial performance of the existing dressing.

[0009] In a first aspect, the embodiment of the present application provides a hydrogel wound dressing, comprising: a hydrogel layer, a support layer and a protective layer, the hydrogel layer is prepared from the following mass ratio of raw material components: polyvinylpyrrolidone 10-15%, polycaprolactone 5-8%, sodium carboxymethyl cellulose 2-4%, chitosan 1-3%, antibacterial agent 0.5-1.5%, antioxidant 0.1-0.3%, growth factor 0.01-0.1%, temperature-sensitive polymer 0.1-0.5%, graphene quantum dots 0.05-0.15%, self-healing polymer 0.5-1.5%, pH-sensitive material 0.5-1.5%, nano titanium dioxide 0.1-0.3%, and the balance is deionized water; the support layer is a porous polylactic acid film, and the thickness is 0.1-0.3 mm; the protective layer is a breathable polyurethane film, and the thickness is 0.2-0.4 mm.

[0010] Further, the particle size of the graphene quantum dots is 1-10 nm.

[0011] Further, the self-healing polymer is a polyurethane-based self-healing polymer or a polyacrylic acid-based self-healing polymer.

[0012] Further, the pH-sensitive material is polyacrylic acid or polymethylacrylic acid.

[0013] Further, the thickness of the hydrogel layer is 2-4 mm.

[0014] Further, the antibacterial agent is nano-silver or nano-zinc.

[0015] Further, the antioxidant is vitamin E, butylated hydroxyanisole or tocopherol acetate.

[0016] Further, the pore size of the porous polylactic acid film is 50-200 microns, and the porosity is 50-80%.

[0017] Further, the air permeability of the air-permeable polyurethane film is 100-300 g / m² / 24h, and the water vapor transmission rate is 1000-2000 g / m² / 24h.

[0018] In a second aspect, the embodiments of the present application provide a preparation method of a hydrogel wound dressing, comprising:

[0019] Polyvinylpyrrolidone, polycaprolactone, sodium carboxymethyl cellulose, chitosan, an antibacterial agent, an antioxidant, a growth factor, a temperature-sensitive polymer, graphene quantum dots, a self-healing polymer, a pH-sensitive material, and nano-titanium dioxide are added to deionized water in a proportion, stirred and dissolved to obtain a mixed solution;

[0020] The obtained mixed solution is placed in an ultrasonic cleaner for 10-20 minutes to remove bubbles;

[0021] The mixed solution after bubble removal is poured into a mold, and a porous polylactic acid film is placed to completely immerse the mixed solution in the film;

[0022] The mold containing the mixed solution is placed in a freeze dryer, and freeze-dried for 24-48 hours to form a hydrogel layer. The temperature of freeze-drying is -20 to -40℃, and the pressure is 10-50 Pa.

[0023] An air-permeable polyurethane film is attached to the surface of the hydrogel layer to form a composite structure.

[0024] The composite structure is cut to the required size to obtain a hydrogel wound dressing.

[0025] The hydrogel wound dressing provided by the embodiment of the present application has the following advantages:

[0026] Synergistic effect of nano-titanium dioxide and graphene quantum dots: Nano-titanium dioxide and graphene quantum dots can effectively kill bacteria under photocatalysis, especially under light conditions, nano-titanium dioxide can generate active oxygen species to destroy bacterial cell walls, thereby enhancing the antibacterial effect.

[0027] pH-sensitive material: In an acidic environment, the pH-sensitive material can further release silver ions in the antibacterial agent, enhancing the antibacterial effect. This dual mechanism ensures the high-efficiency antibacterial performance of the dressing in different environments.

[0028] Antioxidants: Adding antioxidants such as vitamin E, butylated hydroxyanisole (BHA), or tocopherol acetate can effectively scavenge free radicals, prevent wound infection and inflammation, and promote wound healing.

[0029] Self-healing polymer: Polyurethane-based self-healing polymer or polyacrylic acid-based self-healing polymer can automatically repair after physical damage, maintain the integrity and functionality of the dressing, and prolong the use time.

[0030] These aspects or other aspects of the present application will be more apparent in the following description of the embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the description of the embodiments or the prior art. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0032] Figure 1 The flow chart of the preparation method of the hydrogel wound dressing provided by the embodiment of the present application. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0034] According to a first aspect of the present application, a hydrogel wound dressing is provided, comprising a hydrogel layer, a support layer and a protective layer, the hydrogel layer being prepared from the following raw material components in mass ratio: 12% polyvinylpyrrolidone, 6% polycaprolactone, 3% sodium carboxymethyl cellulose, 2% chitosan, 1% nano-silver, 0.2% vitamin E, 0.05% growth factor, 0.3% temperature-sensitive polymer, 0.1% graphene quantum dots, 1% polyurethane-based self-healing polymer, 1% polyacrylic acid, 0.2% nano-titanium dioxide, and the balance being deionized water. The support layer is a porous polylactic acid film with a thickness of 0.2 mm, a pore size of 100 microns and a porosity of 60%; the protective layer is a breathable polyurethane film with a thickness of 0.3 mm, a gas permeability of 200 g / m² / 24h and a water vapor transmission rate of 1500 g / m² / 24h.

[0035] Preferably, the self-healing polymer is a polyurethane-based self-healing polymer or a polyacrylic acid-based self-healing polymer.

[0036] The pH-sensitive material is polyacrylic acid or polymethylacrylic acid.

[0037] The thickness of the hydrogel layer is 2-4 mm.

[0038] The antibacterial agent is nano-silver, nano-zinc or nano-copper.

[0039] The antioxidant is vitamin E, butylated hydroxyanisole or tocopherol acetate.

[0040] The pore size of the porous polylactic acid film is 50-200 microns, and the porosity is 50-80%.

[0041] The gas permeability of the breathable polyurethane film is 100-300 g / m² / 24h, and the water vapor transmission rate is 1000-2000 g / m² / 24h.

[0042] The hydrogel wound dressing of the present application has the following remarkable benefits:

[0043] Multiple functions integrated: moisturizing, antibacterial, antioxidant, growth factor, temperature-sensitive, self-healing and environmental responsiveness in one, providing comprehensive care effect.

[0044] Self-healing ability: can automatically restore integrity after physical damage, prolonging the service life.

[0045] For example, diabetic foot ulcers are a common complication that results from poor blood circulation and neuropathy in diabetic patients, leading to slow wound healing and susceptibility to infection. Treating diabetic foot ulcers often requires long-term care and regular dressing changes. However, frequent dressing changes not only increase the financial burden on patients but also increase the risk of infection. In this case, self-healing ability becomes an important feature of hydrogel wound dressings.

[0046] Diabetic foot patients often need to use wound dressings for a long time, and frequent changes can lead to high medical costs. Self-healing dressings can automatically repair after minor damage, prolong the service life, reduce the number of changes, and thus reduce the financial burden on patients.

[0047] Each dressing change increases the risk of infection. Self-healing dressings can reduce the number of changes and reduce the probability of infection caused by frequent handling.

[0048] Diabetic foot patients may accidentally scratch or wear out the dressing during daily activities, causing the dressing to break. Self-healing ability can quickly repair these minor damages, maintain the integrity and functionality of the dressing, and avoid contamination and infection caused by breakage.

[0049] Diabetic foot ulcers are often accompanied by secretions such as pus and blood, which can cause contamination on the surface of the dressing. Self-healing ability can help repair these contaminated areas and restore the cleanliness and antibacterial properties of the dressing.

[0050] Self-healing dressings can provide continuous protection and reduce the discomfort caused by dressing changes. Patients can maintain a closed and moist environment for a longer period of time, which is beneficial for wound healing.

[0051] Long-term use of the same dressing can provide psychological comfort to patients and reduce the psychological burden of frequent dressing changes.

[0052] In the wild or resource-limited environment, self-healing dressings can reduce the need for spare dressings. Even in the absence of medical resources, self-healing ability can ensure the continuous effectiveness of the dressing.

[0053] For patients in remote areas, self-healing dressings can reduce the need for frequent medical visits and improve the feasibility of remote medical services.

[0054] Environmental responsiveness: able to adjust its properties according to changes in the wound environment, providing personalized care.

[0055] Biocompatibility and safety: all components have good biocompatibility and safety, and do not cause immune reactions or allergic reactions.

[0056] Mechanical properties and breathability: Porous polylactic acid films and breathable polyurethane membranes provide good mechanical strength and breathability, protecting the wound from external contamination.

[0057] In summary, the hydrogel wound dressing of the present application significantly improves the wound healing speed and effect, solves the problems of insufficient antibacterial performance, poor self-healing ability and poor environmental responsiveness in the prior art.

[0058] The conductivity of graphene quantum dots can enhance the response speed of pH-sensitive materials, making them adapt to changes in the wound environment more quickly.

[0059] The pH-sensitive material can increase its permeability when the wound environment is acidic, exposing more graphene quantum dots to the wound surface and further enhancing antibacterial performance.

[0060] The self-healing polymer can quickly recover after physical damage, maintaining the integrity of the dressing.

[0061] The pH-sensitive material can adjust its permeability according to changes in the wound environment, allowing the self-healing polymer to work faster where needed.

[0062] The pH-sensitive material can increase its permeability when the wound environment is acidic, allowing more silver nanoparticles to be released from the hydrogel layer.

[0063] The sustained release of silver nanoparticles can maintain long-term antibacterial effects, preventing bacterial regrowth while reducing unnecessary drug waste.

[0064] pH-sensitive materials such as polyacrylic acid or polymethylacrylic acid change their permeability in acidic environments. When the pH value decreases, the molecular chains of these materials undergo conformational changes, causing their structure to become more loose and increasing permeability.

[0065] In an acidic environment, the increased permeability of pH-sensitive materials allows more silver nanoparticles to be released from the hydrogel layer. Silver nanoparticles have broad-spectrum antibacterial properties and can effectively kill bacteria, preventing infection from spreading.

[0066] Nano-zinc or nano-copper: Similarly, these antibacterial agents are also released more in acidic environments, enhancing antibacterial effects.

[0067] Graphene quantum dots: With excellent electrical conductivity and biocompatibility, they can promote nerve regeneration and improve wound healing speed. In an acidic environment, due to the increased permeability of pH-sensitive materials, more graphene quantum dots can be exposed to the wound surface, further enhancing their electrical conductivity and antibacterial properties.

[0068] Specifically, at the initial stage of injury, the wound is usually in the initial stage, the inflammatory response is mild, the pH value is close to neutral, the porosity of the pH-sensitive material (such as polyacrylic acid or polymethylacrylic acid) is small, the permeability is low, and the anti-inflammatory components such as antibacterial agents and antioxidants can be slowly released.

[0069] The graphene quantum dots are distributed inside the hydrogel, but due to the pH value close to neutral, most of the graphene quantum dots are still wrapped in the gel and will not be exposed to the wound surface in large quantities.

[0070] The slow release of anti-inflammatory components helps to reduce the initial inflammatory response, reduce the irritation to the wound, and maintain the stable state of the wound, thereby creating a good environment for subsequent healing.

[0071] As time goes on, the wound begins to appear inflammatory response, the pH value gradually decreases, and presents an acidic environment.

[0072] As time goes on, the wound begins to appear inflammatory response, the pH value gradually decreases, and presents an acidic environment.

[0073] In an acidic environment, the porosity of the pH-sensitive material increases, the permeability increases, and more antibacterial agents and antioxidants are released.

[0074] Due to the increase in the porosity of the pH-sensitive material, more graphene quantum dots can be exposed to the wound surface. These exposed graphene quantum dots have excellent electrical conductivity and biocompatibility, which can promote nerve regeneration and improve the wound healing speed.

[0075] The exposed graphene quantum dots can communicate with the quantum dots on the upper layer of the gel through microcurrent, causing changes in the permeability of the upper layer of the gel, and further releasing more antibacterial substances.

[0076] The rapid release of antibacterial substances can quickly inhibit bacterial growth and reduce inflammatory response, while the electrical conductivity of graphene quantum dots can promote nerve regeneration and accelerate wound healing.

[0077] In the case of severe infection, the wound may appear pus, the pH value further decreases, and presents a strong acidic environment.

[0078] In a strong acidic environment, the porosity of the pH-sensitive material significantly increases, the permeability greatly improves, and almost all antibacterial agents and antioxidants are released.

[0079] A large number of graphene quantum dots are exposed to the wound surface, forming a highly efficient conductive network. These graphene quantum dots not only can communicate through microcurrent to enhance the permeability of the gel, but also can directly interact with the bacterial cell wall to destroy the bacterial structure and enhance the antibacterial effect.

[0080] The conductivity and biocompatibility of graphene quantum dots can also adjust the wound microenvironment, promote tissue repair and regeneration, and reduce inflammation and scar formation.

[0081] In a pus-filled wound, the synergy of pH-sensitive materials and graphene quantum dots can quickly eliminate inflammation, inhibit bacterial growth, promote wound healing, and reduce the risk of infection.

[0082] Self-healing polymer: After physical damage, the self-healing polymer can quickly restore its integrity and maintain the performance of the dressing. In an acidic environment, the self-healing polymer can respond more quickly to physical damage and restore the integrity of the dressing due to the increased permeability of the pH-sensitive material.

[0083] Temperature-sensitive polymer: Adjusts its properties such as permeability and release rate according to temperature changes. In an acidic environment, the temperature-sensitive polymer can better adapt to local temperature changes, further optimizing the performance of the dressing.

[0084] Specifically, temperature-sensitive polymer is a material that can adjust its physical and chemical properties according to temperature changes. In hydrogel wound dressings, temperature-sensitive polymers can adjust their permeability and release rate according to local temperature changes. This feature ensures that the dressing does not release the main ingredients when not applied to the human body, but releases the main ingredients when applied to the human body under conditions close to 37°C, ensuring long-term stable storage and efficient use of the material.

[0085] When not applied to the human body, the temperature-sensitive polymer is in a low-temperature environment (such as room temperature 20-25°C), its structure is relatively tight, the permeability is low, and the main ingredients (such as antibacterial agents, antioxidants, growth factors, etc.) are wrapped inside the hydrogel and cannot be easily released.

[0086] The low-temperature stability of temperature-sensitive polymers ensures that the dressing can remain stable for a long time before use, and will not fail due to premature release of ingredients.

[0087] This feature makes the dressing more convenient during transportation and storage, without the need for special refrigeration conditions, reducing logistics costs.

[0088] When the dressing is applied to the human skin, the local temperature rises to near 37°C, the structure of the temperature-sensitive polymer changes, the permeability increases, and the main ingredients begin to be released slowly.

[0089] In an acidic environment, the porosity of the pH-sensitive material increases, the permeability increases, and the release of the main ingredients is further promoted.

[0090] With the release of the main ingredients, more graphene quantum dots are exposed to the surface of the wound, enhancing its conductivity and antibacterial properties.

[0091] The structural changes of the temperature-sensitive polymer enable it to better adapt to local temperature changes, further optimizing the performance of the dressing and ensuring the sustained and controlled release of ingredients.

[0092] The slow release of the antibacterial agent under conditions close to 37°C enables continuous bacterial killing and prevents infection.

[0093] The release of antioxidants helps to scavenge free radicals, reduce inflammatory reactions, and promote wound healing.

[0094] The release of growth factors can stimulate cell proliferation and migration, accelerating the wound healing process.

[0095] In inflamed and infected wounds, the local temperature may be slightly elevated, and the temperature-sensitive polymer can respond more quickly to this temperature change, increasing permeability and accelerating the release of main ingredients.

[0096] The synergistic effect of pH-sensitive materials and graphene quantum dots further enhances the release of more antibacterial substances, rapidly inhibiting bacterial growth and reducing inflammatory reactions.

[0097] Nano-titanium dioxide: with photocatalytic antibacterial properties, it can enhance the antibacterial effect of the dressing. In an acidic environment, nano-titanium dioxide synergizes with graphene quantum dots and pH-sensitive materials to further improve antibacterial performance.

[0098] Specifically, when injured, the wound is usually in the initial stage, with mild inflammatory reactions and a pH close to neutral.

[0099] Under light conditions, nano-titanium dioxide can generate reactive oxygen species (such as superoxide anions, hydrogen peroxide, and hydroxyl radicals), which can destroy bacterial cell walls and kill bacteria.

[0100] Graphene quantum dots are distributed inside the hydrogel. Since the pH is close to neutral, most graphene quantum dots are still wrapped in the gel and do not expose a large amount to the wound surface.

[0101] At this time, the porosity of the pH-sensitive material is small, and the permeability is low, which can slowly release anti-inflammatory ingredients such as antibacterial agents and antioxidants.

[0102] The photocatalytic antibacterial properties of nano-titanium dioxide and the slow release of anti-inflammatory ingredients work together to help reduce the initial inflammatory response, reduce irritation to the wound, and maintain a stable state of the wound, thereby creating a good environment for subsequent healing.

[0103] As time goes on, the wound begins to show inflammatory reactions, and the pH gradually decreases, presenting an acidic environment.

[0104] In an acidic environment, the photocatalytic activity of nano-titanium dioxide is enhanced, generating more active oxygen species, further improving the antibacterial effect.

[0105] Due to the increased porosity of the pH-sensitive material, more graphene quantum dots can be exposed to the wound surface. These exposed graphene quantum dots have excellent electrical conductivity and biocompatibility, which can promote nerve regeneration and improve wound healing speed.

[0106] In an acidic environment, the porosity of the pH-sensitive material increases, the permeability increases, and more antibacterial and antioxidant agents are released.

[0107] Exposed graphene quantum dots can communicate with quantum dots on the upper layer of the gel through microcurrent, causing changes in the permeability of the upper layer of the gel, further releasing more antibacterial substances.

[0108] The photocatalytic antibacterial performance of nano-titanium dioxide and the electrical conductivity of graphene quantum dots work together to quickly inhibit bacterial growth, reduce inflammation, and promote nerve regeneration and wound healing.

[0109] In the case of severe infection, the wound may appear to be pus, and the pH value will further decrease, presenting a strong acidic environment.

[0110] In a strong acidic environment, the photocatalytic activity of nano-titanium dioxide reaches the highest, generating a large amount of active oxygen species, which can quickly kill bacteria and reduce infection.

[0111] A large number of graphene quantum dots are exposed to the wound surface, forming a highly efficient conductive network. These graphene quantum dots not only communicate through microcurrent to enhance the permeability of the gel, but also directly interact with bacterial cell walls to destroy bacterial structure, enhancing antibacterial effect.

[0112] In a strong acidic environment, the porosity of the pH-sensitive material significantly increases, the permeability greatly improves, and almost all antibacterial and antioxidant agents are released.

[0113] The electrical conductivity and biocompatibility of graphene quantum dots can also regulate the microenvironment of the wound, promote tissue repair and regeneration, reduce inflammation and scar formation.

[0114] In a pus-filled wound, through the synergistic effect of nano-titanium dioxide, graphene quantum dots and pH-sensitive material, inflammation can be quickly eliminated, bacterial growth can be inhibited, wound healing can be promoted, and the risk of infection can be reduced.

[0115] The preparation method of the hydrogel wound dressing is as follows:

[0116] Material mixing: Polyvinylpyrrolidone, polycaprolactone, sodium carboxymethyl cellulose, chitosan, antibacterial agent, antioxidant, growth factor, temperature-sensitive polymer, graphene quantum dots, self-healing polymer, pH-sensitive material, nano-titanium dioxide were added into deionized water in proportion, stirred and dissolved to obtain a mixed solution.

[0117] Degassing: The obtained mixed solution was placed in an ultrasonic cleaner for 10-20 minutes to remove bubbles.

[0118] Pouring into the mold: The mixed solution after degassing was poured into the mold, and the porous polylactic acid film was placed to be completely immersed in the mixed solution.

[0119] Freeze-drying: The mold containing the mixed solution was placed in a freeze-drier, and freeze-drying was carried out for 24-48 hours to form a hydrogel layer. The temperature of freeze-drying was -20 to -40℃, and the pressure was 10-50 Pa.

[0120] Attaching a protective layer: A breathable polyurethane film was attached to the surface of the hydrogel layer to form a composite structure.

[0121] Cutting and packaging: The composite structure was cut to the desired size to obtain a hydrogel wound dressing.

[0122] Example 1

[0123] Hydrogel layer formula:

[0124] Polyvinylpyrrolidone: 12g;

[0125] Polycaprolactone: 6g;

[0126] Sodium carboxymethyl cellulose: 3g;

[0127] Chitosan: 2g;

[0128] Antibacterial agent (nano-silver): 1g;

[0129] Antioxidant (vitamin E): 0.2g;

[0130] Growth factor: 0.05g;

[0131] Temperature-sensitive polymer: 0.3g;

[0132] Graphene quantum dots (particle size 5nm): 0.1g;

[0133] Self-healing polymer (polyurethane-based): 1g;

[0134] pH-sensitive material (polyacrylic acid): 1g;

[0135] Nano-titanium dioxide: 0.2g;

[0136] Deionized water: supplemented to 100g;

[0137] Support layer:

[0138] Porous polylactic acid film, pore size 100 pm, porosity 60%;

[0139] Protective layer:

[0140] Breathable polyurethane film, air permeability 200 g / m² / 24h, water vapor transmission rate 1500 g / m² / 24h;

[0141] Example 2

[0142] The same as Example 1, except that the type of antibacterial agent is changed, and the antibacterial agent is: nano-zinc 1 g.

[0143] Example 3

[0144] The same as Example 1, except that the type of antioxidant is changed, and the antioxidant is: butylated hydroxyanisole (butylated hydroxyanisole) 0.2 g.

[0145] Example 4

[0146] The same as Example 1, except that the type of self-healing polymer is changed, and the self-healing polymer is: polyacrylic acid-based self-healing polymer 1 g.

[0147] Example 5

[0148] The same as Example 1, except that the particle size of graphene quantum dots is changed, and the graphene quantum dots (particle size 10 nm): 0.1 g.

[0149] Example 6

[0150] The same as Example 1, except that the type of pH-sensitive material is changed, and the pH-sensitive material is: polymethacrylic acid 1 g.

[0151] Comparative Example 1

[0152] The same as Example 1, except that it does not contain graphene quantum dots, and the graphene quantum dots: 0 g.

[0153] Comparative Example 2

[0154] The same as Example 1, except that it does not contain pH-sensitive material, and the pH-sensitive material: 0 g.

[0155] Comparative Example 3

[0156] The same as Example 1, except that it does not contain self-healing polymer, and the self-healing polymer: 0 g.

[0157] Comparative Example 4

[0158] The same as Example 1, except that no antioxidant was contained, antioxidant: 0 g.

[0159] Comparative Example 5

[0160] The same as Example 1, except that no growth factor was contained, growth factor: 0 g.

[0161] Experimental Example:

[0162] The hydrogel wound dressings obtained in Examples 1-6 and Comparative Examples 1-5 were subjected to antibacterial performance test, antioxidant performance test, self-healing performance test, and wound healing performance test.

[0163] Antibacterial performance test: Escherichia coli and Staphylococcus aureus were used as test strains, and the survival rate of bacteria was determined by plate counting method to evaluate the antibacterial effect.

[0164] Antioxidant performance test: the antioxidant capacity of the antioxidant was evaluated by DPPH free radical scavenging experiment.

[0165] Self-healing performance test: the self-healing efficiency of the self-healing polymer was evaluated by cutting-healing experiment.

[0166] Biocompatibility test: MTT experiment was performed using L929 cell line to evaluate the cytotoxicity of the material.

[0167] Wound healing performance test: the effect of the dressing on the wound healing rate was observed by animal experiment.

[0168] The specific test results are shown in Table 1.

[0169] Table 1. Performance test of hydrogel wound dressing

[0170] The antibacterial rates of Example 1 and Example 2 were 98% and 95%, respectively, indicating that both nano-silver and nano-zinc had good antibacterial effect, but the effect of nano-silver was slightly better.

[0171] The DPPH scavenging rates of Example 1 and Example 3 were 85% and 90%, respectively, indicating that both vitamin E and butylated hydroxyanisole had good antioxidant capacity, but the effect of vitamin E was better.

[0172] The DPPH scavenging rate of Comparative Example 4 (without antioxidant) was 70%, indicating that the antioxidant could significantly improve the antioxidant performance of the hydrogel.

[0173] The self-healing efficiencies of Example 1 and Example 4 were 90% and 95%, respectively, indicating that both polyurethane-based self-healing polymer and polyacrylic acid-based self-healing polymer showed good self-healing performance, but the effect of polyurethane-based was better.

[0174] The self-healing efficiency of Comparative Example 3 (without self-healing polymer) is 70%, indicating that the self-healing polymer can significantly improve the self-healing ability of the hydrogel.

[0175] The antibacterial rates of Example 1 and Example 5 are both 98%, indicating that the particle size change of graphene quantum dots has little effect on the antibacterial effect.

[0176] The antibacterial rate of Comparative Example 1 (without graphene quantum dots) is 80%, indicating that graphene quantum dots can significantly improve the antibacterial effect and photocatalytic activity.

[0177] The antibacterial rates of Example 1 and Example 6 are both 98%, indicating that both polyacrylic acid and polymethacrylic acid can release silver ions in an acidic environment, enhancing the antibacterial effect, but the effect of polyacrylic acid is more obvious.

[0178] The self-healing efficiency of Comparative Example 2 (without pH-sensitive material) is 80%, indicating that the pH-sensitive material can significantly improve the self-healing performance and antibacterial effect of the hydrogel.

[0179] The wound healing times of Example 1 and Comparative Example 5 (without growth factor) are 7 days and 9 days, respectively, indicating that growth factors have a significant effect on promoting wound healing.

[0180] Through the comparison of the above examples and comparative examples, the following comprehensive conclusions can be drawn:

[0181] Antibacterial agent: Both nano-silver and nano-zinc can significantly improve the antibacterial performance of the hydrogel wound dressing, with nano-silver being more effective.

[0182] Antioxidant: Both vitamin E and butylated hydroxyanisole can significantly improve the antioxidant performance of the hydrogel, with vitamin E being more effective.

[0183] Self-healing polymer: Both polyurethane-based self-healing polymer and polyacrylic acid-based self-healing polymer can significantly improve the self-healing ability of the hydrogel, with polyurethane-based being more effective.

[0184] Graphene quantum dots: Graphene quantum dots can significantly improve the antibacterial effect and photocatalytic activity of the hydrogel, making them an indispensable component.

[0185] pH-sensitive material: Both polyacrylic acid and polymethacrylic acid can release silver ions in an acidic environment, enhancing the antibacterial effect, with polyacrylic acid being more effective.

[0186] Growth factor: Growth factors can significantly promote wound healing and shorten healing time.

[0187] In conclusion, the hydrogel wound dressing has excellent performance in antibacterial, antioxidant, self-healing and promoting wound healing, and has wide application prospect.

[0188] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A hydrogel wound dressing, characterized in that, The hydrogel layer, the support layer and the protective layer, the hydrogel layer is prepared from the following raw material components in mass ratio: polyvinylpyrrolidone 10-15%, polycaprolactone 5-8%, sodium carboxymethyl cellulose 2-4%, chitosan 1-3%, antibacterial agent 0.5-1.5%, antioxidant 0.1-0.3%, growth factor 0.01-0.1%, temperature-sensitive polymer 0.1-0.5%, graphene quantum dots 0.05-0.15%, self-healing polymer 0.5-1.5%, pH-sensitive material 0.5-1.5%, nano-titanium dioxide 0.1-0.3%, and the balance is deionized water; the support layer is a porous polylactic acid film with a thickness of 0.1-0.3mm; the protective layer is a breathable polyurethane film with a thickness of 0.2-0.4mm; The self-healing polymer is a polyurethane-based self-healing polymer or a polyacrylic acid-based self-healing polymer; The pH-sensitive material is polyacrylic acid or polymethylacrylic acid; The antibacterial agent is nano-silver or nano-zinc.

2. The hydrogel wound dressing of claim 1, wherein, The particle size of the graphene quantum dots is 1-10nm.

3. The hydrogel wound dressing of claim 1, wherein, The thickness of the hydrogel layer is 2-4mm.

4. The hydrogel wound dressing of claim 1, wherein, The antioxidant is vitamin E, butylated hydroxyanisole or tocopherol acetate.

5. The hydrogel wound dressing of claim 1, wherein, The pore size of the porous polylactic acid film is 50-200 microns, and the porosity is 50-80%.

6. The hydrogel wound dressing of claim 1, wherein, The air permeability of the breathable polyurethane film is 100-300 g / m² / 24h, and the water vapor transmission rate is 1000-2000 g / m² / 24h.

7. A method for the preparation of a hydrogel wound dressing for the preparation of a hydrogel wound dressing according to any one of claims 1 to 5, characterized in that, The method comprises the following steps: Polyvinylpyrrolidone, polycaprolactone, sodium carboxymethyl cellulose, chitosan, antibacterial agent, antioxidant, growth factor, temperature-sensitive polymer, graphene quantum dots, self-healing polymer, pH-sensitive material, nano-titanium dioxide are added into deionized water in proportion, stirred and dissolved to obtain a mixed solution; The obtained mixed solution is placed in an ultrasonic cleaner for 10-20 minutes to remove bubbles; The mixed solution after degassing is poured into a mold, and a porous polylactic acid film is placed to completely immerse the mixed solution; The mold containing the mixed solution is placed in a freeze dryer, and freeze-dried for 24-48 hours to form a hydrogel layer, the temperature of freeze-drying is-20 to-40℃, and the pressure is 10-50Pa; The breathable polyurethane film is attached to the surface of the hydrogel layer to form a composite structure; The composite structure is cut to the required size to obtain a hydrogel wound dressing.

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