An antibacterial hydrogel for promoting wound healing and preparation method thereof

Abstract

The invention discloses an antibacterial hydrogel for promoting wound healing and a preparation method thereof, and belongs to the technical field of skin dressings. The hydrogel dressing is mainly composed of carbomer, arginine, copper peroxide and water. While providing a moist healing environment for the wound, the dressing can release hydrogen peroxide and copper ions to kill bacteria at the wound, and the released arginine can promote wound healing and repair. The dressing solves the problem that traditional hydrogel dressings cannot prevent and treat wound infection, and does not contain antibiotics, silver ions and hormone drugs, has little side effects, and is safer to use. The dressing can be applied to the treatment of acute and chronic wounds, has the functions of preventing infection, assisting in clearing infection and promoting wound healing, and has high clinical application value.

Description

Technical Field

[0001] The invention relates to the technical field of skin dressings, and in particular to an antibacterial hydrogel for promoting wound healing and a preparation method thereof. Background Art

[0002] Skin is the largest organ in the human body. It is an important barrier for the human body to resist external damage and an important immune organ of the human body. Skin barrier damage and defects caused by skin diseases, burns, chronic ulcers and mechanical trauma, especially large-area damage, have always been a major challenge faced by clinical needs. As a temporary skin barrier substitute, skin dressings need to play an important role in protecting the wound, stopping bleeding, preventing infection, and promoting wound healing.

[0003] Hydrogel dressings are a type of wet dressing that is mainly composed of hydrophilic natural or synthetic polymers and water, and may contain auxiliary materials and functional additives such as polyols, oils, stabilizers, antimicrobial agents, and the water content can be as high as 80-90%, or even higher. Common hydrophilic polymers include modified cellulose, pectin, chitosan, polyvinyl pyrrolidone, polyacrylamide, polyethylene oxide, etc. Hydrogel dressings have a certain water absorption effect. While providing a moist environment to the wound surface, they can also absorb excess exudate from the wound surface and dissipate it to the outside world, and have good exudate management capabilities; the moist environment provided by hydrogel dressings can promote granulation and endothelial cell proliferation; in addition, hydrogel dressings also have the advantages of cooling and strong breathability. Hydrogel dressings can be divided into shaped hydrogels and amorphous hydrogel dressings according to their different deformation abilities. Amorphous hydrogel dressing products such as IntraSite TM Gel (Smith & Nephews) has the advantages of being easy to apply and fill, can better fit the wound surface, and is easy to use.

[0004] Wound infection often occurs when the care is improper or the patient's immune system is weak (such as patients with large-area burns and diabetic patients). Wound infection will cause further deterioration of the wound, and the wound will not heal, which will bring greater pain and risks to the patient, as well as greater economic burden and mental stress. Therefore, in addition to the physical barrier and humidity regulation functions, the ideal wound dressing should also have the functions of preventing infection and antibacterial, and can further promote wound healing to a certain extent.

[0005] Traditional hydrogel dressings only have the function of protecting and providing a moist healing environment. The hydrogel itself is rich in water and has large holes and gaps between the hydrogel matrix, which makes it difficult to block the invasion of external pathogens. The hydrogel itself often needs to add preservatives or use disposable packaging to ensure its own sterility. The development of hydrogel dressings with antibacterial functions can reduce the use of antibiotics and has very important practical significance for the care and treatment of wounds and wounds. The antibacterial hydrogel products currently on the market are generally loaded with silver and triclocarban, and the safety of these two antibacterial agents has been questioned. Therefore, it is very necessary to develop safer and more effective antibacterial hydrogel dressings. Summary of the invention

[0006] The purpose of the present invention is to provide an antibacterial hydrogel for promoting wound healing and a preparation method thereof, so as to solve the problems in the background technology. In addition to ensuring good mechanical protection, humidity regulation and firm adhesion performance, the hydrogel also has good antibacterial effect, safety and the function of accelerating wound healing.

[0007] To achieve the above-mentioned object, the present invention provides an antibacterial hydrogel for promoting wound healing, comprising carbomer, arginine, copper peroxide and water; wherein the mass percentage of carbomer is 0.5-10%, the mass percentage of copper peroxide is 0.001-1%, the mass ratio of arginine to carbomer is 0.67-1.5, and the rest is water.

[0008] The present invention also provides a method for preparing the above-mentioned antibacterial hydrogel for promoting wound healing, comprising the following steps:

[0009] S1, preparing copper peroxide aqueous dispersion;

[0010] S2, dispersing carbomer in an aqueous solution and degassing to prepare a carbomer aqueous dispersion, and dissolving arginine in an aqueous solution to prepare an arginine aqueous solution;

[0011] S3, adding the arginine aqueous solution to the carbomer aqueous dispersion and mixing to neutralize, then adding the copper peroxide aqueous dispersion thereto, stirring and mixing evenly to form a hydrogel containing copper peroxide.

[0012] Preferably, the specific preparation process of step S1 is:

[0013] Arginine and copper salt are mixed and added to an aqueous solution to dissolve to obtain an arginine-copper salt aqueous solution, into which an aqueous hydrogen peroxide solution is added dropwise while stirring, and the stirring reaction is continued for 2-15 minutes. The copper peroxide slurry is washed by centrifugation to obtain a copper peroxide slurry, which is redispersed in water to obtain a copper peroxide aqueous dispersion.

[0014] Preferably, the copper salt provides divalent copper ions, and the copper salt is one or more of copper chloride, copper sulfate, and copper nitrate.

[0015] Preferably, in the arginine-copper salt aqueous solution, the arginine content is 0.005-0.2M, and the copper ion content is 0.005-0.2M.

[0016] Preferably, the concentration of hydrogen peroxide is 2-10 M, and the amount of the hydrogen peroxide added dropwise is 1.2-25 times the amount of the copper ion substance.

[0017] The carbomer used in the present invention, also known as carbopol, is a type of polyacrylic acid polymer with a certain degree of crosslinking, and is a commonly used gelling agent in the medical and cosmetic fields. It has strong hydrophilicity, is acidic when dissolved in water, and increases in viscosity after neutralization, becoming a thixotropic gel. Carbomer has good gelation, adhesion, emulsification, suspension and film-forming properties, and has stable and safe chemical properties, no irritation and allergic reactions, and is a high-quality raw material commonly used in the preparation of amorphous hydrogels.

[0018] Arginine used in the present invention is an essential amino acid for the human body and is also one of the common neutralizers in the cosmetic and pharmaceutical fields. Arginine is a substrate for endogenous synthesis of nitric oxide. In the human body, it can be decomposed by the iNOS enzyme to produce nitric oxide (NO). NO is a small signal molecule in the human body that can promote the production of capillaries, thereby improving the nutritional status of the damaged area and promoting tissue regeneration. At the same time, NO can also directly bind to bacterial DNA to interfere with its genetic recombination, disrupting bacterial proliferation and division; and NO can react with endogenous superoxide in bacteria to generate reactive nitrogen species (RNS) such as nitric oxide free radicals, and exert antibacterial effects on bacteria through oxidation or nitrosation in multiple ways.

[0019] Copper peroxide is an efficient and safe antibacterial agent prepared based on hydrogen peroxide. Hydrogen peroxide (hydrogen peroxide) is a commonly used disinfectant in medical processes. It has strong oxidizing properties and has a good disinfecting effect on skin and wounds at concentrations above 1%. After decomposition, it eventually produces non-toxic species such as oxygen and water, which has long-term safety. However, high-concentration hydrogen peroxide, while sterilizing, will also irritate the wound surface, causing strong pain and damaging healthy tissues exposed to the human body and new granulation tissue, causing secondary damage to the wound surface and slowing down the wound healing process. To address this defect, PVP-stabilized copper peroxide nanoparticles have been prepared by using hydrogen peroxide and copper ions in the presence of sodium hydroxide and polyvinyl pyrrolidone (PVP) as stabilizers. The copper peroxide prepared by it can remain stable in neutral and weakly alkaline environments. Inflammation and bacterial infection sites are often slightly acidic. Copper peroxide slowly decomposes in this slightly acidic environment, releasing hydrogen peroxide and copper ions. The released hydrogen peroxide decomposes under the catalytic action of copper ions to produce hydroxyl free radicals with higher antibacterial efficacy, thereby achieving effective bactericidal and antibacterial effects at lower concentrations.

[0020] The present invention adopts a more suitable preparation method according to the characteristics of its own gel, and uses arginine as an alkalizing agent and a stabilizer to prepare a copper peroxide aqueous dispersion. Arginine itself, as one of the important raw materials in the preparation process of amorphous hydrogel, can not only provide a weak alkaline environment for the preparation of copper peroxide particles to stabilize the product and prevent decomposition; at the same time, amino acids, as metal ligands with good safety, can also coordinate on the surface of copper peroxide, passivate the particle surface and perform hydrophilic modification, play a role in stabilizing the particles to prevent agglomeration and enhancing water solubility; the preparation of copper peroxide is precisely combined with the preparation of hydrogel, which reduces the introduction of other substances and reduces the purification and quantitative difficulty of materials.

[0021] Therefore, the present invention provides an antibacterial hydrogel for promoting wound healing and a preparation method thereof, which has the following beneficial effects:

[0022] (1) The hydrogel dressing prepared by the present invention uses carbomer as a gelling agent, arginine as a neutralizing agent, and copper peroxide as an antibacterial additive. The three main raw materials are all raw materials with excellent performance and safe properties;

[0023] (2) The amorphous hydrogel dressing prepared by the present invention not only has good mechanical protection, humidity regulation and strong adhesion properties, but also has good antibacterial effect, safety and the function of promoting wound healing.

[0024] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The figure is a schematic diagram of the preparation method of the amorphous hydrogel dressing of the present invention;

[0026] Figure 2 This is a microscopic image of copper peroxide particles obtained in step 1 of the embodiment of the present invention;

[0027] Figure 3 This is a comparison chart of the in vitro antibacterial effect of the antibacterial amorphous hydrogel dressing prepared in the embodiments of the present invention;

[0028] Figure 4 This is a graph showing the results of an in vitro cytotoxicity test of the copper peroxide particles prepared in step 1 of an embodiment of the present invention;

[0029] Figure 5 This is a comparison chart of the therapeutic effects of the amorphous hydrogel dressing prepared in an embodiment of the present invention on a diabetic rat skin wound model;

[0030] Figure 6This is a comparison chart of the therapeutic effects of the amorphous hydrogel dressing prepared in an embodiment of the present invention in assisting the treatment of bacterial infection in a mouse skin wound infection model. DETAILED DESCRIPTION

[0031] The invention provides an antibacterial hydrogel for promoting wound healing, comprising carbomer, arginine, copper peroxide and water; wherein the mass percentage of carbomer is 0.5-10%, the mass percentage of copper peroxide is 0.001-1%, the mass ratio of arginine to carbomer is 0.67-1.5, and the rest is water.

[0032] The present invention also provides a method for preparing the above-mentioned antibacterial hydrogel for promoting wound healing, the flow diagram of which is as follows: Figure 1 As shown, the specific steps include:

[0033] S1, preparing copper peroxide aqueous dispersion;

[0034] Arginine and copper salt are mixed and added to an aqueous solution to dissolve, and an arginine-copper salt aqueous solution having an arginine content of 0.005-0.2M and a copper ion content of 0.005-0.2M is prepared, and a hydrogen peroxide aqueous solution having a concentration of 2-10M is added dropwise thereto under stirring, and the total amount of hydrogen peroxide added dropwise is 1.2-25 times the total amount of copper ion substances. After the dropwise addition is completed, stirring is continued for 2-15 minutes to complete the reaction, and the precipitate is collected by centrifugation, and the precipitate is washed twice with pure water to remove excess copper salt, hydrogen peroxide and arginine, and the obtained precipitate is redispersed in purified water to obtain an arginine-stabilized copper peroxide aqueous dispersion.

[0035] S2, dispersing carbomer in an aqueous solution and degassing to prepare a carbomer aqueous dispersion, and dissolving arginine in an aqueous solution to prepare an arginine aqueous solution;

[0036] S3. Under stirring, the arginine aqueous solution is added to the carbomer aqueous dispersion and mixed to neutralize, and then the copper peroxide aqueous dispersion is added thereto, and the mixture is stirred and mixed to form a hydrogel containing copper peroxide.

[0037] In the present invention, the copper salt functions to provide divalent copper ions, so the copper salt is a divalent salt of copper that dissolves well in water, including but not limited to copper chloride, copper sulfate, copper nitrate and a mixture thereof.

[0038] According to the preparation method described above, carbomer is a gelling agent, arginine is a neutralizing agent, and copper peroxide is an antibacterial functional additive. Carbomer is a general term for a class of substances with different grades, and carbomers of different grades have different rheological properties. Different grades can be selected according to different requirements for the final product, and carbomers of different grades can be used in combination. The concentration of carbomer affects the viscosity of the final gel. Generally, for the same grade of carbomer, the higher the concentration, the higher the viscosity of the final product; arginine, as a neutralizing agent, can increase the pH value of the acidic carbomer dispersion. Generally, under mild pH conditions, the higher the addition ratio of arginine to carbomer, the higher the pH value of the system, and the greater the viscosity of the system. In specific practice, gel products with different rheological behaviors, viscosities and pH values ​​can be obtained by adjusting the grade, ratio, concentration of carbomer and the concentration of arginine.

[0039] According to the above formula, other excipients can also be added to the gel as needed, such as polyols as viscosity regulators, oils as emollients, preservatives for maintaining a sterile environment, and various nutrients, vitamins, etc. The addition of the above excipients is a common understanding of ordinary technicians with certain professional knowledge in this field, and is a technical solution that can be obtained without creative work. For ordinary technicians in this field, without paying creative work, the technical solution obtained by adding the above excipients to the product disclosed by the present invention still belongs to the scope of the present invention.

[0040] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. Any other changes, modifications, substitutions, combinations, and simplifications made without violating the spirit and principle of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention. In addition, it should be understood that after reading the contents of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application, and all belong to the scope of protection of the present invention.

[0041] Reference to "embodiment" herein means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present application. The term "embodiment" appearing in various places in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or association with other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the various technical features mentioned in the embodiments can be combined in any way to form a corresponding implementable technical solution.

[0042] Unless otherwise defined, the technical terms used in this document have the same meanings as those generally understood by those skilled in the art to which this application belongs; the use of relevant terms in this document is only for describing specific embodiments and is not intended to limit this application.

[0043] Unless otherwise specified in the present invention, the reagents, instruments, equipment, etc. used in the following examples are all reagents, instruments, and equipment commonly used by technicians in this field.

[0044] Example

[0045] This embodiment provides a method for preparing an antibacterial hydrogel for promoting wound healing, comprising the following steps:

[0046] 1. Preparation of copper peroxide particles

[0047] Prepare 0.01M arginine aqueous solution mother solution, 0.01M copper chloride aqueous solution mother solution, 10M hydrogen peroxide aqueous solution, stir and mix 5mL arginine aqueous solution mother solution and 5mL copper chloride aqueous solution mother solution, at this time the solution appears blue, add 0.1mL 10M hydrogen peroxide, the solution becomes a yellow-brown turbid liquid, continue stirring to make it fully react. Centrifuge the obtained yellow-brown suspension, collect the yellow-brown precipitate at the bottom, wash twice with water to remove excess unreacted substances and excessive arginine, obtain copper peroxide slurry, freeze-dry and store.

[0048] For comparison, the arginine in step 1 was replaced with the common inorganic base sodium hydroxide to prepare a reference substance. The copper peroxide prepared by the sodium hydroxide method directly formed a flocculent precipitate in the absence of an additional surfactant and could not be suspended / dispersed in an aqueous solution.

[0049] The prepared copper peroxide particles were dispersed in anhydrous ethanol by stirring, and then dropped onto the coated copper grid. After drying, the particles were observed under TEM. Figure 2 , it can be seen that the prepared copper peroxide is a layered particle with wrinkles. Compared with the copper peroxide prepared by sodium hydroxide, the copper peroxide particles prepared by the preparation method of this embodiment can be stably dispersed and suspended in water without the assistance of additional surfactants, while the copper peroxide prepared by the sodium hydroxide method is a flocculent precipitate and is difficult to disperse.

[0050] 2. Preparation of antibacterial amorphous hydrogel dressing containing copper peroxide

[0051] 1. Weigh a certain amount of Carbomer (981), slowly add a certain amount of pure water under high-speed stirring to fully disperse it in the water, and then let it stand overnight to allow it to absorb water and swell, thereby obtaining a hydrated Carbomer aqueous dispersion;

[0052] 2. Weigh a certain amount of arginine, stir and add into water to prepare arginine aqueous solution;

[0053] 3. Take the copper peroxide slurry prepared in step 1 and stir and disperse it in pure water to obtain a copper peroxide aqueous dispersion;

[0054] 4. Under stirring, evacuate the hydrated carbomer aqueous dispersion to remove a large amount of air mixed therein; then slowly add the prepared arginine aqueous solution under stirring. With the addition of arginine, the viscosity of the system gradually increases to form a gel; take a certain amount of copper peroxide aqueous dispersion, add it to the gel, continue stirring to make the whole system evenly dispersed, and the antibacterial amorphous hydrogel can be obtained.

[0055] Some hydrogel formulas are listed below and the pH value test and property stability test of the hydrogel were performed; in order to facilitate the comparison needs of other tests, sample I is a reference sample without copper peroxide particles, as shown in Table 1 below, wherein the samples are all made using Carbomer 981.

[0056] The pH value test adopts the direct detection method, that is, direct detection using a pH meter, burying the glass electrode of the pH meter directly in the gel, and reading the pH value after the instrument reading stabilizes.

[0057] The gel stability test mentioned above mainly refers to the test of the stability of copper peroxide in hydrogel. Copper peroxide itself is yellow-brown, and its decomposition product copper ions will produce blue. Therefore, the change in gel color can be used to determine whether the copper peroxide in the gel is decomposed. The gel that changes color within one day is marked as -, the gel that does not change color within one day but changes color within a week is marked as +, and the gel that remains unchanged for more than one week is marked as ++. Through stability observation, it can be found that when the pH value of the gel is close to neutral, the copper peroxide particles in the gel are more stable. When the pH value of the gel is acidic, it will promote the decomposition of copper peroxide. The stronger the acidity, the more unstable it is.

[0058] Table 1 A series of hydrogel dressing formulations (mass ratio), pH value and stability

[0059]

[0060] Table 1 includes near-neutral samples II and IV with better stability, slightly acidic sample III with slightly worse stability, and neutral reference sample I without copper peroxide addition.

[0061] The performance of the amorphous hydrogels prepared with the above-mentioned different proportions was tested.

[0062] 1. Test of antibacterial effect of amorphous hydrogel

[0063] The antibacterial properties of the selected gel samples were evaluated according to the method described in 5.1.2 Carrier immersion quantitative antibacterial test of the standard WS / T 650-2019 Antibacterial and antibacterial effect evaluation method. The test strains were Gram-negative bacteria Escherichia coli (E. coli.) 8099 strain and Gram-positive bacteria Staphylococcus aureus (S. au.) ATCC 6538 strain.

[0064] The test method is briefly described as follows: Prepare 10 7 The CFU / mL concentration suspension was set aside, 10 μL was added to a sterilized 10 mm × 10 mm degreased plain cotton cloth, and the infected carrier was obtained after drying at room temperature. It was completely immersed in 5 g of gel sample, incubated at 37 ° C for 2 h, and then the infected carrier was taken out and placed in a sterile test tube containing 5 mL of PBS. The test bacteria were washed off, and the eluate was diluted 100 times and then applied to the corresponding agar medium plate. After culturing for 48 h, the bacterial growth on the agar surface was observed. A control sample with the same material as the test sample but without antibacterial ingredients was taken as a positive control. The amount of bacteria recovered in the positive control should be 1.0 × 10 4 CFU / piece~9.0×10 4 CFU / tablet.

[0065] In this test, samples II, III, and IV were selected as test samples, and sample I without copper peroxide was used as a positive control sample. The bacterial culture results of the test can be found in the attached Figure 3 After two hours of gel contact incubation, compared with gel sample I without copper peroxide, the bacterial colonies grown on the agar plates of several gel dressing samples with copper peroxide added were significantly reduced, all showing obvious antibacterial effects. Among them, the antibacterial rate of sample II with 0.1% copper peroxide added was >50%, while the antibacterial rates of samples III and IV with 0.3% copper peroxide added were over 90%.

[0066] It can be seen from the above that the gel dressing prepared by the present invention has obvious inhibitory or killing effects on both model bacteria, has certain antibacterial properties, and can be used for wound infection prevention and auxiliary treatment of infected wounds.

[0067] 2. In vitro cytotoxicity test

[0068] The product prepared by the present invention is a water-absorbing amorphous hydrogel, which absorbs water and dilutes in an aqueous phase liquid to become a viscous liquid, so it is not possible to use a traditional extraction method to prepare a cytotoxicity test sample. Among the main components of the gel, carbomer and arginine are mature and safe medical materials, and their cytotoxicity does not need to be further investigated, and there is no chemical interaction between the components of the dressing when used. Therefore, the cytotoxicity of the functional granular copper peroxide is examined here alone, which can represent the enhanced extraction safety of the dressing to a certain extent.

[0069] NIH 3T3 mouse embryonic fibroblasts were used as model cells, and DMEM medium supplemented with 10% fetal bovine serum, penicillin and streptomycin was used as the complete medium for the experiment. After the cells were revived, they were cultured for 3 generations. After the cell state was restored, the experiment was officially carried out. The cells were inoculated in a 96-well plate with an inoculation density of about 10,000 cells per well. They were cultured for one day at 37°C and 5% CO2 atmosphere to allow the cells to adhere to the wall and grow. The cell confluence reached about 80%. The original culture medium was aspirated, and complete culture medium (pH 7.24~7.4) containing different concentrations of copper peroxide particles was added for co-culture. After incubation for 24 hours at 37°C and 5% CO2 atmosphere, the old culture medium was aspirated and rinsed 3 times with PBS to thoroughly wash away the added copper peroxide particles and their decomposition products. The cell activity was tested using a commercial CCK-8 cell activity test kit. The test results are shown in the attached figure. Figure 4 As shown, compared with the control group without copper peroxide particles, when high concentration (1 mg / mL) of copper peroxide particles were added, the activity of cells was inhibited, showing certain toxicity, but still higher than the standard of 70% relative activity. When lower concentrations of copper peroxide were added, the activity of cells was enhanced, indicating that at lower concentrations, copper peroxide particles have the ability to promote the proliferation of mouse embryonic fibroblasts. The above not only shows that the appropriate use of copper peroxide has a certain biosafety, but also indicates that amorphous hydrogel dressings with a certain amount of copper peroxide particles may have the ability to promote cell proliferation, thereby promoting wound / wound healing.

[0070] 3. Experiment on promoting skin wound healing in diabetic rats with amorphous hydrogel

[0071] In order to verify whether the hydrogel product prepared by the present invention has the function of promoting wound healing, a treatment test on diabetic wounds, a chronic wound, was conducted. Sample I was selected as a dressing sample without copper peroxide particles, and sample IV was selected as a representative sample of amorphous hydrogel dressing containing copper peroxide for comparative test.

[0072] 6-8 week old male SD rats were selected as test subjects, weighing about 200-250 g. The rats were induced to develop diabetic symptoms by intraperitoneal injection of streptozotocin (STZ). After induction, the rat tail vein blood glucose was monitored and continuously higher than 16.7 mmol / L for one week, which was considered a successful model.

[0073] After depilation, diabetic rats were selected to create a full-thickness skin injury with a diameter of about 8 mm on the back, and a suture silicone ring was pasted around the wound to inhibit the contraction of the rat skin. Rats with skin trauma were treated with different dressings to cover the wound, and the dressings were changed daily. When changing the dressing, the old dressing was thoroughly rinsed with sterile saline, and the surface moisture was wiped dry with sterile gauze before covering with a new dressing. The wound healing process was observed and the wound area was counted.

[0074] The test results are as follows Figure 5 As shown, in the test group without additional treatment, the wound area was reduced in the early stage due to dry wound and wound edge contraction, while the wounds treated with the two hydrogels did not reduce or even slightly increased due to wound edge hydration; after a plateau period of 3 or 4 days, the wound closure speed of the wounds treated with gel dressings was accelerated, and compared with the wounds without additional treatment, the wounds treated with gel dressings had a faster wound closure speed; and the wounds treated with the amorphous hydrogel dressings with copper peroxide particles prepared by the present invention had a significantly faster closure speed than the other two test groups after the early plateau period, indicating that the hydrogel product prepared by the present invention has the advantage of promoting wound healing in wound treatment.

[0075] IV. Experiment on the treatment of mouse skin wound infection with amorphous hydrogel

[0076] In order to clarify the actual antibacterial effect of the antibacterial amorphous hydrogel dressing prepared by the present invention, an infection clearance test was conducted on a mouse animal model, that is, after the infected wound surface was treated, the bacteria loaded on the wound surface were cultured on an agar plate to observe the degree of infection.

[0077] Take about 20g ICR mice as test subjects, remove hair from the back of the mice before the experiment, and then cut a full-thickness skin defect with a diameter of 8mm on the back. After hemostasis, apply a physiological saline suspension of Staphylococcus aureus to the manufactured skin defect. After the bacterial solution is dried, apply a polyurethane transparent film to close the wound, incubate for 24 hours, and allow bacteria to infect the wound surface. The modeling is completed. During treatment, the gel sample prepared by the present invention is applied to the entire wound area with a thickness of 1mm~2mm. The dressing is changed every day. When changing the dressing, the old gel is rinsed with sterile physiological saline, the wound and the surrounding skin are wiped dry with sterile gauze, and the corresponding gel dressing is applied. After 3 days of treatment, the wound tissue is sampled and put into a tissue grinding tube with sterile grinding beads and sterile physiological saline (1mL / 0.1g) to grind to release the bacteria loaded in the tissue, take the tissue grinding solution and dilute it 10 times and apply it on an agar plate culture medium, and observe the results after culturing for 48 hours.

[0078] The culture results are shown in Figure 6 , it can be seen that the bacteria infected in the wound surface without treatment after 3 days cannot be cleared by the mouse's own immune system, so additional means are needed for auxiliary antibacterial treatment; sample I is a hydrogel dressing without antibacterial properties, it can be seen that the dressing provides a moist and gentle environment, and even causes the proliferation of infected bacteria; sample II is a near-neutral hydrogel dressing with 0.1% copper peroxide particles added. After 3 days of treatment, the amount of bacteria loaded on the wound surface has been significantly reduced, and the bacterial load has been reduced by more than 50%; and after 3 days of treatment with the antibacterial hydrogel dressing sample III with a higher copper peroxide content, almost no infected bacteria can be detected on the wound surface, showing a very excellent antibacterial treatment effect. This experiment confirms that the antibacterial amorphous hydrogel dressing prepared by the present invention still shows a good antibacterial effect when used in animal experiments.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A method for preparing an antibacterial hydrogel for promoting wound healing, characterized in that: The antibacterial hydrogel comprises carbomer, arginine, copper peroxide and water; wherein the mass percentage of carbomer is 0.5-10%, the mass percentage of copper peroxide is 0.001-1%, the mass ratio of arginine to carbomer is 0.67-1.5, and the rest is water; The preparation method comprises the following steps: S1, preparing copper peroxide aqueous dispersion; S2, dispersing carbomer in an aqueous solution and degassing to prepare a carbomer aqueous dispersion, and dissolving arginine in an aqueous solution to prepare an arginine aqueous solution; S3, adding the arginine aqueous solution to the carbomer aqueous dispersion, mixing and neutralizing, then adding the copper peroxide aqueous dispersion thereto, stirring and mixing evenly to form a hydrogel containing copper peroxide; The specific preparation process of step S1 is: Arginine and copper salt are mixed and added to an aqueous solution to dissolve to obtain an arginine-copper salt aqueous solution, into which an aqueous hydrogen peroxide solution is added dropwise while stirring, and the stirring reaction is continued for 2-15 minutes. The copper peroxide slurry is washed by centrifugation to obtain a copper peroxide slurry, which is redispersed in water to obtain a copper peroxide aqueous dispersion.

2. The method for preparing an antibacterial hydrogel for promoting wound healing according to claim 1, characterized in that: The copper salt provides divalent copper ions, and the copper salt is one or more of copper chloride, copper sulfate, and copper nitrate.

3. The method for preparing an antibacterial hydrogel for promoting wound healing according to claim 2, characterized in that: In the arginine-copper salt aqueous solution, the arginine content is 0.005-0.2M, and the copper ion content is 0.005-0.2M.

4. The method for preparing an antibacterial hydrogel for promoting wound healing according to claim 2, characterized in that: The concentration of hydrogen peroxide is 2-10M, and the amount of the hydrogen peroxide added dropwise is 1.2-25 times the amount of the copper ion.

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