Nano antibacterial dressing and preparation method thereof

Abstract

The invention discloses a nano antibacterial dressing and a preparation method thereof, and belongs to the technical field of pharmaceutical preparations. According to the nano-antibacterial dressing, mupirocin serves as an antibacterial component, chitosan, zein, tragacanth, sodium hyaluronate, sodium butyrate, a cross-linking agent, a humectant and other components are supplemented, and the nano-antibacterial dressing has efficient antibacterial performance, outstanding stability and simple preparation process and has important application value in wound healing and infection prevention and control.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of pharmaceutical preparations, and particularly relates to a nano-antibacterial dressing and a preparation method thereof. BACKGROUND

[0002] Traditional wound dressings such as gauze and absorbent cotton have certain moisture absorption and protection effects, but have obvious limitations: first, they have poor antibacterial performance and cannot effectively inhibit the growth of bacteria at the wound site; second, they have poor moisture retention performance and can easily cause the wound to dry and scab, hindering the migration of epithelial cells and the growth of granulation tissue; and third, they have poor adhesion to the wound and can easily cause secondary damage when replaced, increasing the patient's pain.

[0003] To solve the above problems, various functional antibacterial dressings have emerged, including silver-containing dressings, antibiotic dressings, and biopolymer dressings. Silver-containing dressings have broad-spectrum antibacterial effects, but the accumulation of silver ions can cause cytotoxicity and skin pigmentation and other side effects; traditional antibiotic dressings can easily lead to the development of bacterial drug resistance in long-term use, and the release of drugs is difficult to control, and a high local concentration can inhibit tissue repair. Biopolymer materials such as chitosan and sodium hyaluronate are widely used in dressing preparation due to their good biocompatibility and biodegradability, but their antibacterial effect is limited when used alone, and their mechanical properties and stability need to be improved.

[0004] In recent years, the application of nanotechnology in the field of biological medicine has provided a new direction for the development of antibacterial dressings. Nanocarrier systems can improve the targeting and bioavailability of drugs, achieve slow release of antibacterial components, and prolong the action time; at the same time, the small size effect of nanoparticles helps to enhance the interaction between the dressing and the wound tissue, improve the adhesion and permeability. Chinese Patent No. CN111793900A discloses a chitosan / poly-caprolactone composite nanofiber membrane material, which is prepared by the following steps: preparing a poly-caprolactone solution and adding mupirocin; preparing a chitosan solution and adding lidocaine hydrochloride; loading the above-mentioned solutions into the feeding device of the electrospinning equipment, respectively, and spraying the solutions onto the fiber receiver to form; and drying to remove the solvent to obtain the composite nanofiber membrane. Chinese Patent No. CN106039394A discloses a medical composite chitosan gel containing an antibacterial drug, which comprises the following components in parts by weight: 0.5-10 parts of a chitosan-based polymer material, 0.05-2 parts of an antibacterial drug, 0-10 parts of a thickening agent, 1-25 parts of a humectant, and 53-98.45 parts of purified water.

[0005] However, the existing nano-antibacterial dressings still have some problems in stability: the compatibility of the effective components such as drugs and the carrier in some formulations is poor, which leads to chemical structure change or activity loss of the effective components due to environmental (such as temperature, pH value) fluctuations, and significant decrease in stability; the stability of some nano-carrier materials is poor, and aggregation, degradation or structure damage of the materials easily occur during storage or use, leading to decrease in overall performance of the dressing.

[0006] Therefore, it has important clinical significance and application value to develop a nano-antibacterial dressing with high efficiency, simple preparation process and outstanding stability for promoting wound healing and reducing the risk of infection. SUMMARY

[0007] To overcome the shortcomings of the prior art, the present application provides a nano-antibacterial dressing and a preparation method thereof. The dressing takes mupirocin as the antibacterial active ingredient, takes chitosan and corn protein as the nano-carrier matrix, and is supplemented with biological macromolecular materials such as tragacanth gum, sodium hyaluronate and sodium caseinate. Through reasonable formulation design and step-by-step preparation process, a hydrogel dressing with high efficiency and excellent stability is formed.

[0008] Specifically, the nano-antibacterial dressing formula of the present application includes, by weight: mupirocin 0.2-0.6 parts, chitosan 3-7 parts, corn protein 0.8-1.7 parts, tragacanth gum 0.35-0.9 parts, sodium hyaluronate 12-22 parts, sodium caseinate 1-3 parts, crosslinking agent 0.6-1.4 parts, humectant 40-80 parts, and appropriate amount of PBS buffer, acetic acid solution (mass fraction 0.5-1.5%), pH adjuster and deionized water.

[0009] The preparation method of the nano-antibacterial dressing of the present application includes two steps: (1) Chitosan nanoparticle preparation: chitosan and corn protein are dissolved in acetic acid solution and heated to dissolve to obtain phase A, the crosslinking agent is dissolved in deionized water, then mupirocin and tragacanth gum are added and ultrasonically dispersed to obtain phase B, phase B is added to phase A at a rate of 0.3-0.7 mL / min under stirring, and the stirring is continued to form a drug-loaded nanoparticle suspension; (2) Hydrogel preparation: sodium hyaluronate and sodium caseinate are dissolved in PBS buffer (pH 7.0-7.8), the drug-loaded nanoparticle suspension is added and stirred, the humectant is slowly added and the stirring is continued, the pH adjuster is added to adjust the pH to 6.0-7.5, and then the crosslinking is carried out to obtain the hydrogel.

[0010] Compared with the prior art, the technical effect of the present application is that: (1) High efficiency and stable antibacterial performance: The application takes mupirocin as the core antibacterial ingredient, and realizes drug release through a chitosan-corn protein composite nanocarrier; the accelerated test (40℃ / 75% RH, 6 months) shows that the mupirocin content is higher than 99%, the inhibition rate of pathogenic bacteria such as Staphylococcus aureus and Escherichia coli is still above 98%, and the antibacterial effect is long-term stable.

[0011] (2) Excellent physical and chemical stability: The nanoparticle particle size of the nanometer antibacterial dressing of the application changes little after 6 months of storage, the Zeta potential is stable, and there is no obvious aggregation; the hydrogel system has small viscosity fluctuation, no stratification and precipitation, the pH value is maintained in the physiological suitable range, and the structural stability is significantly better than that of the comparative example; it is proved that the synergistic effect of corn protein and chitosan enhances the stability of the nanocarrier, tragacanth reduces drug exposure, and the gel network formed by sodium caseinate and sodium hyaluronate further protects the drug, and together inhibits the degradation of the components. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 : Mupirocin content stability.

[0013] Figure 2 : Inhibition rate after 6 months of accelerated test. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical scheme of the application more clear, the following embodiments are used to further illustrate the application, but the protection scope of the application is not limited to these embodiments, and the embodiments are only used to explain the application. Those skilled in the art should understand that any change or equivalent replacement without departing from the concept of the application is included in the protection scope of the application.

[0015] Example 1: Nanometer antibacterial dressing Formula: Preparation method: (1) Preparation of chitosan nanoparticles: chitosan and corn protein were weighed and dissolved in 100 mL of 1.0% acetic acid solution together, and magnetic stirring was carried out at 50℃ water bath until complete dissolution, to obtain a composite solution (phase A). The crosslinking agent was dissolved in 50 mL of deionized water, and mupirocin and tragacanth were added and ultrasonically dispersed for 15 min (power 300 W, ice bath temperature control), to obtain a mixed solution (phase B). Under the stirring of 400 rpm, phase B was added to phase A at a rate of 0.5 mL / min, and after the drop was completed, the stirring was continued for 40 min, to form a drug-loaded nanoparticle suspension.

[0016] (2) Preparation of hydrogel: sodium hyaluronate and sodium caseinate were dissolved in 50 mL of PBS buffer (pH 7.4), and the above nanoparticle suspension was added, and magnetic stirring was performed for 2.0 h. 6 mL of humectant was slowly added, and stirring was continued for 35 min, and the pH of the system was adjusted to 6.8 with a pH adjuster. The system was allowed to stand at room temperature for 1.5 h to allow the system to crosslink completely to form a gel, and a mupirocin chitosan nanometer antibacterial hydrogel dressing was obtained.

[0017] Example 2 Nanometer antibacterial dressing Formulation: Preparation method: (1) Preparation of chitosan nanoparticles: chitosan and corn protein were weighed and dissolved in 80 mL of 0.5% acetic acid solution together, and magnetic stirring was performed in a 40°C water bath until complete dissolution to obtain a composite solution (phase A). The crosslinking agent was dissolved in 30 mL of deionized water, and mupirocin and tragacanth gum were added and ultrasonically dispersed for 10 min (power 250 W, ice bath temperature control), to obtain a mixed solution (phase B). Under stirring at 300 rpm, phase B was added to phase A at a rate of 0.3 mL / min, and after the drop was completed, stirring was continued for 30 min to form a drug-loaded nanoparticle suspension.

[0018] (2) Preparation of hydrogel: sodium hyaluronate and sodium caseinate were dissolved in 30 mL of PBS buffer (pH 7.0), and the above nanoparticle suspension was added, and magnetic stirring was performed for 1.0 h. 4 mL of humectant was slowly added, and stirring was continued for 25 min, and the pH of the system was adjusted to 6.0 with a pH adjuster. The system was allowed to stand at room temperature for 0.5 h to allow the system to crosslink completely to form a gel, and a mupirocin chitosan nanometer antibacterial hydrogel dressing was obtained.

[0019] Example 3 Nanometer antibacterial dressing Formulation: Preparation method: (1) Preparation of chitosan nanoparticles: chitosan and corn protein were weighed and dissolved in 80 mL of 0.5% acetic acid solution together, and magnetic stirring was performed in a 40°C water bath until complete dissolution to obtain a composite solution (phase A). The crosslinking agent was dissolved in 30 mL of deionized water, and mupirocin and tragacanth gum were added and ultrasonically dispersed for 10 min (power 250 W, ice bath temperature control), to obtain a mixed solution (phase B). Under stirring at 300 rpm, phase B was added to phase A at a rate of 0.3 mL / min, and after the drop was completed, stirring was continued for 30 min to form a drug-loaded nanoparticle suspension.

[0020] (2) Preparation of hydrogel: sodium hyaluronate and sodium caseinate were dissolved in 70 mL of PBS buffer (pH 7.8), and the above nanoparticle suspension was added, and magnetic stirring was performed for 2.5 h. 8 mL of humectant was slowly added, and stirring was continued for 45 min, and the pH of the system was adjusted to 7.5 with a pH adjuster. The system was allowed to stand at room temperature for 2.5 h to allow the system to crosslink completely to form a gel, and a mupirocin chitosan nanometer antibacterial hydrogel dressing was obtained.

[0021] Comparative Example 1: Nanometer antibacterial dressing (without adding corn prolamine) Formulation: Preparation method: (1) Preparation of chitosan nanoparticles: chitosan was weighed and dissolved in 100 mL of 1.0% acetic acid solution, and magnetic stirring was performed in a 50°C water bath until complete dissolution to obtain a complex solution (phase A). The crosslinking agent was weighed and dissolved in 50 mL of deionized water, and mupirocin and tragacanth gum were added and ultrasonically dispersed for 15 min (power 300 W, ice bath temperature control), to obtain a mixed solution (phase B). Under stirring at 400 rpm, phase B was added to phase A at a rate of 0.5 mL / min, and after the drop was completed, stirring was continued for 40 min to form a drug-loaded nanoparticle suspension.

[0022] (2) Preparation of hydrogel: sodium hyaluronate and sodium caseinate were dissolved in 50 mL of PBS buffer (pH 7.4), and the above nanoparticle suspension was added, and magnetic stirring was performed for 2.0 h. 6 mL of humectant was slowly added, and stirring was continued for 35 min, and the pH of the system was adjusted to 6.8 with a pH adjuster. The system was allowed to stand at room temperature for 1.5 h to allow the system to crosslink completely to form a gel, and a mupirocin chitosan nanometer antibacterial hydrogel dressing was obtained.

[0023] Comparative Example 2: Nanometer antibacterial dressing (gelatin was used instead of tragacanth gum) Formulation: Preparation method: (1) Preparation of chitosan nanoparticles: chitosan and corn prolamine were weighed and dissolved in 100 mL of 1.0% acetic acid solution, and magnetic stirring was performed in a 50°C water bath until complete dissolution to obtain a complex solution (phase A). The crosslinking agent was weighed and dissolved in 50 mL of deionized water, and mupirocin and gelatin were added and ultrasonically dispersed for 15 min (power 300 W, ice bath temperature control), to obtain a mixed solution (phase B). Under stirring at 400 rpm, phase B was added to phase A at a rate of 0.5 mL / min, and after the drop was completed, stirring was continued for 40 min to form a drug-loaded nanoparticle suspension.

[0024] (2) Preparation of hydrogel: sodium hyaluronate and sodium caseinate were dissolved in 50 mL of PBS buffer (pH 7.4), and the above nanoparticle suspension was added, and magnetic stirring was performed for 2.0 h. 6 mL of humectant was slowly added, and stirring was continued for 35 min, and the pH of the system was adjusted to 6.8 with a pH adjuster. The system was allowed to stand at room temperature for 1.5 h to allow the system to crosslink completely to form a gel, and a mupirocin chitosan nanometer antibacterial hydrogel dressing was obtained.

[0025] Comparative Example 3: Nanometer antibacterial dressing (soy protein is used instead of zein) Formulation: Preparation method: (1) Preparation of chitosan nanoparticles: chitosan and soy protein were weighed and dissolved in 100 mL of 1.0% acetic acid solution together, and magnetic stirring was performed in a 50°C water bath until complete dissolution to obtain a composite solution (phase A). The crosslinking agent was dissolved in 50 mL of deionized water, and mupirocin and tragacanth gum were added and ultrasonically dispersed for 15 min (power 300 W, ice bath temperature control), to obtain a mixed solution (phase B). Under stirring at 400 rpm, phase B was added to phase A at a rate of 0.5 mL / min, and after the addition was completed, stirring was continued for 40 min to form a drug-loaded nanoparticle suspension.

[0026] (2) Preparation of hydrogel: sodium hyaluronate and sodium caseinate were dissolved in 50 mL of PBS buffer (pH 7.4), and the above nanoparticle suspension was added, and magnetic stirring was performed for 2.0 h. 6 mL of humectant was slowly added, and stirring was continued for 35 min, and the pH of the system was adjusted to 6.8 with a pH adjuster. The system was allowed to stand at room temperature for 1.5 h to allow the system to crosslink completely to form a gel, and a mupirocin chitosan nanometer antibacterial hydrogel dressing was obtained.

[0027] Comparative Example 4: Nanometer antibacterial dressing (without sodium caseinate) Formulation: Preparation method: (1) Preparation of chitosan nanoparticles: chitosan and soy protein were weighed and dissolved in 100 mL of 1.0% acetic acid solution together, and magnetic stirring was performed in a 50°C water bath until complete dissolution to obtain a composite solution (phase A). The crosslinking agent was dissolved in 50 mL of deionized water, and mupirocin and tragacanth gum were added and ultrasonically dispersed for 15 min (power 300 W, ice bath temperature control), to obtain a mixed solution (phase B). Under stirring at 400 rpm, phase B was added to phase A at a rate of 0.5 mL / min, and after the addition was completed, stirring was continued for 40 min to form a drug-loaded nanoparticle suspension.

[0028] (2) Preparation of hydrogel: sodium hyaluronate and sodium carboxymethyl cellulose were dissolved in 50 mL of PBS buffer (pH 7.4), and the above nanoparticle suspension was added, and magnetically stirred for 2.0 h. Slowly add 6 mL of humectant, continue to stir for 35 min, adjust the pH of the system to 6.8 with pH adjuster. Stand at room temperature for 1.5 h, so that the system is fully cross-linked to form a gel, and the mupirocin chitosan nanometer antibacterial hydrogel dressing is obtained.

[0029] Comparative Example 5 Nanometer antibacterial dressing (sodium carboxymethyl cellulose is used instead of sodium tyroate) Formulation: Preparation method: (1) Preparation of chitosan nanoparticles: chitosan and corn protein were weighed and dissolved in 100 mL of 1.0% acetic acid solution, and magnetically stirred in a 50°C water bath until completely dissolved to obtain a composite solution (phase A). The crosslinking agent was weighed and dissolved in 50 mL of deionized water, and mupirocin and tragacanth gum were added and ultrasonically dispersed for 15 min (power 300 W, ice bath temperature control), to obtain a mixed solution (phase B). Under stirring at 400 rpm, phase B was added to phase A at a rate of 0.5 mL / min, and after the drop was completed, stirring was continued for 40 min to form a drug-loaded nanoparticle suspension.

[0030] (2) Preparation of hydrogel: sodium hyaluronate and sodium carboxymethyl cellulose were dissolved in 50 mL of PBS buffer (pH 7.4), and the above nanoparticle suspension was added, and magnetically stirred for 2.0 h. Slowly add 6 mL of humectant, continue to stir for 35 min, adjust the pH of the system to 6.8 with pH adjuster. Stand at room temperature for 1.5 h, so that the system is fully cross-linked to form a gel, and the mupirocin chitosan nanometer antibacterial hydrogel dressing is obtained.

[0031] Physical stability test Sample preparation: the nanometer antibacterial dressings prepared in Examples 1-3 and Comparative Examples 1-5 were taken respectively, and each dressing was divided into 3 groups, with 3 parallel samples in each group.

[0032] Storage conditions: the samples were stored in a constant temperature incubator at 37°C, and stored for 6 months.

[0033] Measurement method: an appropriate amount of sample was diluted with deionized water to a concentration that met the measurement requirements of the dynamic light scattering instrument, and was thoroughly mixed. The particle size distribution and Zeta potential of the nanoparticles were measured using a dynamic light scattering instrument (DLS), and each sample was measured 3 times, and the average value was taken.

[0034] Table 1 Particle size distribution and Zeta potential Table 1 shows that the nanoparticles of Examples 1-3 have no obvious aggregation, good dispersibility, and meet the requirements of physical stability, indicating that the synergistic effect of the components (corn protein, tragacanth gum, sodium caseinate) in the formulation of the examples effectively maintains the structural stability of the nanoparticles and inhibits aggregation.

[0035] Gel performance determination Viscosity determination: The samples were stored in a constant temperature incubator at 37°C for 6 months, and the viscosity of the dressing was determined at 25°C using a rotational viscometer. Each sample was measured 3 times, and the average value was taken.

[0036] pH determination: The pH of the dressing was directly determined using a pH meter. Each sample was measured 3 times, and the average value was taken.

[0037] Appearance observation: The appearance of the dressing was observed by naked eye and microscope, and whether there were delamination, precipitation, color change, etc. was recorded.

[0038] Table 2 Viscosity and pH Table 3 Appearance change Table 2 and Table 3 show that the nano-antibacterial dressing of Examples 1-3, by reasonably matching chitosan, corn protein, tragacanth gum, sodium caseinate and other key components, synergistically improves the dispersibility of nanoparticles, the structural stability of the gel and the uniformity of the system, which is significantly better than the comparative examples, indicating that the synergistic effect of the components in the formulation of the present application is the core to achieve high stability of the dressing, and corn protein, tragacanth gum and sodium caseinate play an irreplaceable role in maintaining stability.

[0039] Chemical stability test The content change of mupirocin in the nano-antibacterial dressing of Examples 1-3 and Comparative Examples 1-5 during the accelerated test was determined by high performance liquid chromatography (HPLC). The accelerated test conditions were 40°C / 75%RH for 6 months.

[0040] Table 4 Mupirocin content change Table 4 shows that the nano-antibacterial dressing of Examples 1-3 of the present application maintains a high stability of mupirocin content during the accelerated test (40°C / 75%RH). The difference from Comparative Examples 1-5 shows that the synergistic effect of chitosan, corn protein, tragacanth gum and sodium caseinate in the formulation of the present application is the key to maintaining the chemical stability of mupirocin. The complex nanocarrier formed by corn protein and chitosan can enhance the stability of drug encapsulation, the thickening and dispersing effect of tragacanth gum reduces the exposure opportunity of the drug, and the gel network formed by sodium caseinate and sodium hyaluronate provides a protective barrier for the drug, and the combination of the above can inhibit the degradation of mupirocin under high temperature and high humidity conditions.

[0041] Antibacterial inhibition of nanometer antibacterial dressing Test samples: Nanometer antibacterial dressings prepared in Examples 1-3 and Comparative Examples 1-5, divided into initial samples and accelerated 6-month samples, 3 parallel samples in each group.

[0042] Strains: Staphylococcus aureus (ATCC25923), Streptococcus (ATCC32210), Escherichia coli (ATCC25922), Pseudomonas aeruginosa (ATCC27853), Candida albicans (ATCC10231) Culture medium: Nutrient agar medium (for bacterial culture), Sabouraud dextrose agar medium (for Candida albicans culture), nutrient broth medium (for bacterial enrichment), Sabouraud dextrose broth medium (for Candida albicans enrichment) Preparation of bacterial solution: Take the slope culture of each strain, inoculate into the corresponding broth medium, Staphylococcus aureus, Streptococcus, Escherichia coli, Pseudomonas aeruginosa are placed in a 37°C constant temperature incubator for 18-24h, Candida albicans is placed in a 30°C constant temperature incubator for 24-48h for enrichment culture. Take the enriched bacterial solution, dilute with sterile normal saline, adjust the concentration of the bacterial solution to 10 6 -10 7 CFU / mL, ready for use.

[0043] Sample treatment: Initial sample: Take the initial nanometer antibacterial dressing of each example and comparative example, dilute with sterile normal saline to a suspension of 1g / mL in mass concentration, ultrasonic dispersion for 10min (power 200W), ready for use. Accelerated 6-month sample: Take each dressing after 6 months of accelerated test, treat the same as 1g / mL suspension, ready for use.

[0044] Bacteriostatic circle experiment (Oxford cup method) Take the corresponding culture medium melted and cooled to 45-50°C, pour about 20mL into a sterile culture dish, after solidification as the bottom layer agar. Take 0.1mL of each bacterial solution prepared above, evenly spread on the surface of the bottom layer agar, after the bacterial solution is absorbed, place 4 sterile Oxford cups equidistantly in each culture dish. Add 100μL of initial sample suspension, accelerated 6-month sample suspension to the Oxford cups respectively, 3 replicates for each treatment. Staphylococcus aureus, Streptococcus, Escherichia coli, Pseudomonas aeruginosa culture dishes are placed in a 37°C constant temperature incubator for 24h, Candida albicans culture dishes are placed in a 30°C constant temperature incubator for 48h.

[0045] Table 5 Diameter of bacteriostatic circle of nanometer antibacterial dressing (mm) Table 5 reflects the bacteriostatic range and initial antibacterial ability of the nano-antibacterial dressing to various pathogenic bacteria, and the retention of antibacterial performance after accelerated storage. The results show that the nano-antibacterial dressing of the embodiment of the application can maintain a relatively optimal bacteriostatic range and stable antibacterial effect whether in the initial state or after long-term storage, indicating that the synergistic effect of the components in the formula of the application can not only ensure the initial antibacterial efficiency of the dressing, but also effectively maintain its long-term antibacterial stability.

[0046] Bacteriostasis rate determination (plate counting method) Take 1 mL of the above adjusted concentration of bacterial solution and add it to 9 mL of different sample suspensions (the final concentration of the sample is 0.1 g / mL), and at the same time set up a control group of sterile normal saline plus bacterial solution, and place it in a corresponding temperature incubator for culture. At 0 h and 24 h of culture, take 1 mL of the above mixture and perform gradient dilution with sterile normal saline, select an appropriate dilution, and take 0.1 mL and spread it on the corresponding agar medium. After culture, count the number of colonies, and calculate the bacteriostasis rate. Bacteriostasis rate = (number of colonies in the control group - number of colonies in the experimental group) / number of colonies in the control group x 100%.

[0047] Table 6: Bacteriostasis rate of nano-antibacterial dressing (%) Table 6 reflects the inhibition intensity of the nano-antibacterial dressing to various pathogenic bacteria and the retention of antibacterial activity after long-term storage. The results show that the formula of the application can synergistically enhance the antibacterial efficiency of the dressing and effectively maintain its long-term antibacterial stability, which is superior to the formula design of the comparative examples.

Claims

1. A nano-antibacterial dressing, characterized in that, The formula of the nano-antibacterial dressing is calculated as follows: mupirocin 0.2-0.6 parts, chitosan 3-7 parts, corn protein 0.8-1.7 parts, tragacanth gum 0.35-0.9 parts, sodium hyaluronate 12-22 parts, sodium caseinate 1-3 parts, crosslinking agent 0.6-1.4 parts, humectant 40-80 parts, PBS buffer solution, acetic acid solution, pH adjuster and deionized water in proper amounts.

2. The nano-antiseptic dressing according to claim 1, characterized in that, The mass fraction of the acetic acid solution is 0.5-1.5%.

3. The nano-antiseptic dressing according to claim 1, characterized in that, The pH of the PBS buffer solution ranges from 7.0 to 7.

8.

4. The nano-antiseptic dressing according to claim 1, characterized in that, The pH adjuster is at least one selected from the group consisting of tris-hydroxymethyl aminomethane buffer solution and phosphate buffer solution.

5. The nano-antiseptic dressing according to claim 1, characterized in that, The humectant is at least one selected from the group consisting of glycerol, propylene glycol and polyethylene glycol-400.

6. The nano-antiseptic dressing according to claim 1, characterized in that, The crosslinking agent is at least one selected from the group consisting of sodium tripolyphosphate, sodium alginate and heparin sodium.

7. The nanofabricated antimicrobial dressing of any one of claims 1-6, wherein, The formula of the nano-antibacterial dressing is calculated as follows: mupirocin 0.4 parts, chitosan 5 parts, corn protein 1.2 parts, tragacanth gum 0.6 parts, sodium hyaluronate 17 parts, sodium caseinate 2 parts, crosslinking agent 1.0 part, humectant 60 parts, PBS buffer solution, acetic acid solution, pH adjuster and deionized water in proper amounts.

8. A method of preparing the nano-antibacterial dressing of claim 1, characterized by, The preparation method is as follows: (1) preparation of chitosan nanoparticles: chitosan and corn protein are dissolved in an acetic acid solution by heating, to obtain phase A; a crosslinking agent is dissolved in deionized water, and mupirocin and tragacanth gum are added and ultrasonicated, to obtain phase B; phase B is added dropwise to phase A under stirring, and the stirring is continued to form a drug-loaded nanoparticle suspension; (2) preparation of hydrogel: sodium hyaluronate and sodium caseinate are dissolved in a PBS buffer solution, and the drug-loaded nanoparticle suspension is added and stirred; a humectant is slowly added and stirred, and the pH is adjusted with a pH adjuster; and the mupirocin chitosan nano-antibacterial hydrogel dressing is obtained after standing.

9. The production method according to claim 8, characterized by, The dropwise addition rate of phase B to phase A is 0.3-0.7 mL / min.

10. The preparation method according to claim 8, characterized in that, The pH is adjusted to 6.0-7.5 with the pH adjuster.

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