Aseptic liquid dressing and method of making same

Abstract

The application relates to the technical field of medical devices, and discloses a sterile liquid dressing and a preparation method thereof. The sterile liquid dressing is obtained by adding EGF, silicon rubber modified chitosan, epoxy group modified quaternary ammonium borate, polyacrylic acid resin IV, ethyl acetate, menthol, polyethylene glycol and purified water into a stirrer and stirring. In the stirring process, a large number of epoxy groups in the epoxy group modified quaternary ammonium borate and phenolic hydroxyl groups in the silicon rubber modified chitosan can produce ring-opening reaction and crosslinking with each other, and are better adsorbed on the surface of the skin, so that the film forming effect is better, and the repair and antibacterial effect on the skin are promoted. The chitosan in the silicon rubber modified chitosan and the quaternary ammonium salt groups in the epoxy group modified quaternary ammonium borate both have good antibacterial effect, and the quaternary ammonium salt in the epoxy group modified quaternary ammonium borate has high substitution degree, so that the antibacterial effect is further improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a sterile liquid dressing and a preparation method thereof. BACKGROUND

[0002] Medical dressings are a kind of medical materials used to temporarily replace the skin and protect the wound after skin injury, which can prevent wound infection and dehydration, provide a moist environment conducive to wound healing, and promote tissue repair. Silicone rubber has good biocompatibility and will not cause adverse reactions or irritation to human tissues, and at the same time, it can help dry human skin, so it is applied in the sterile liquid dressing of the present application, thereby accelerating the recovery of the wound.

[0003] Patent CN112107724 discloses a liquid dressing and a preparation method thereof. The liquid dressing prepared by the present application is safe and non-irritating, can protect the wound from external pollutants and bacterial infection, and at the same time, has the functions of moisturizing and repairing the skin of the wound, but the antibacterial effect needs to be improved. SUMMARY

[0004] (I) Technical problems solved

[0005] In view of the deficiencies of the prior art, the present application provides a sterile liquid dressing and a preparation method thereof, which has good film-forming, antibacterial and repairing effects.

[0006] (II) Technical solutions

[0007] To achieve the above-mentioned purpose, the present application provides the following technical solutions: a sterile liquid dressing, comprising the following components by weight: 0.001-0.002 parts by weight of EGF, 2-3 parts by weight of silicone rubber modified chitosan, 1-3 parts by weight of epoxy modified quaternary ammonium borate, 8-11 parts by weight of polyacrylic acid resin IV, 3-6 parts by weight of ethyl acetate, 0.4-0.6 parts by weight of menthol, 5-9 parts by weight of polyethylene glycol, and 40-60 parts by weight of purified water.

[0008] Preferably, the preparation method of the silicone rubber modified chitosan is as follows:

[0009] Step one: dissolve magnolol and 3-mercaptopropionic acid in 2-4ml dichloromethane under nitrogen protection, stir uniformly, then continue to add benzoin dimethyl ether catalyst, irradiate with 352-365nm ultraviolet light in a dark environment for 2-4h, the power is 40W, after the end, the product is purified by chromatography column, to obtain carboxylated magnolol;

[0010] Step two: carboxylated magnolol, 1-(3-dimethylaminopropyl)-3-ethyl carbodiimide salt is dissolved in 5-7ml of ethanol solvent, stirring at room temperature for 25-40min, then adding N-hydroxysuccinimide, reacting in ice water bath for 1-2h, continue to add 10-13ml of chitosan hydrochloride mixture, control the pH at 4-5.8 at room temperature, reaction for 20-24h, centrifugal the product, and clean with ethanol, finally through dialysis, freeze-drying, to obtain magnolol modified chitosan;

[0011] Step three: add 20-30ml of methanol solvent, 0.12-0.14mmol of polymerization inhibitor dibutyl hydroxytoluene, 0.23-0.27mmol of catalyst chloroplatinic acid tetrahydrofuran solution into the reactor, stirring for 2-4min, continue to add 2.1-2.6mmol of magnolol modified chitosan and 1.9-2.2mmol of silicone rubber, ultrasonic dispersion for 30-40min, reaction at 65-80℃ for 4-6h, cooling, centrifugal, washing, to obtain silicone rubber modified chitosan.

[0012] In the above reaction process, the terminal alkenyl group in magnolol and the thiol group of 3-mercaptopropionic acid undergo a click reaction, introducing carboxyl and alkenyl groups to obtain carboxylated magnolol, then acylation reaction with chitosan hydrochloride mixture, and finally addition reaction with silicone rubber, to obtain silicone rubber modified chitosan.

[0013] Preferably, the molar ratio of magnolol, 3-mercaptopropionic acid, and dimethyl anisole catalyst in step one is (1.3-1.4)mmol:1mmol:(0.2-0.3)mmol.

[0014] Preferably, the molar ratio of carboxylated magnolol, 1-(3-dimethylaminopropyl)-3-ethyl carbodiimide salt, and N-hydroxysuccinimide in step two is 1mmol:(0.1-0.2)mmol:(0.1-0.3)mmol.

[0015] Preferably, the preparation method of the epoxy modified quaternary ammonium borate is:

[0016] S1. Add boronic acid and 1,3-bis(dimethylamino)-2-propanol into 25-35ml of acetone solvent, stirring and dispersing, reacting at 95-110℃ for 6-8h, after the reaction is completed, distillation under reduced pressure, filtering and drying, to obtain tertiary amine boronic acid;

[0017] S2. Add tertiary amine boronic acid and 3-chloropropene into 20-40ml of N,N-dimethylformamide solvent, stirring and dispersing, reacting at 70-85℃ for 10-12h, after the reaction is completed, distillation under reduced pressure, filtering, to obtain alkenyl quaternary ammonium borate;

[0018] S3. 8-12 mmol of the alkenyl quaternary ammonium borate is added to 20-35 ml of N,N-dimethylformamide solvent at 25-30 DEG C, stirred uniformly, then 40-55 mmol of hydrogen peroxide aqueous solution is added, stirred for 3-5 h, after the reaction is completed, stand, distilled under reduced pressure, washed, to obtain the epoxy-modified quaternary ammonium borate.

[0019] In the above reaction process, the esterification reaction of the borate and the hydroxyl group in 1,3-bis(dimethylamino)-2-propanol is carried out, the tertiary amine group is introduced, the tertiary amine borate is obtained, the quaternary ammonium reaction of the chlorine in 3-chloropropene is continued, the quaternary ammonium salt is generated, the alkenyl group is introduced, and finally the epoxidation reaction is carried out under the action of the hydrogen peroxide aqueous solution, so that the epoxy-modified quaternary ammonium borate is obtained.

[0020] Preferably, the molar ratio of the borate and 1,3-bis(dimethylamino)-2-propanol in S1 is 1 mmol:(2.14-2.86) mmol.

[0021] Preferably, the molar ratio of the tertiary amine borate and 3-chloropropene in S2 is 1 mmol:(3.5-4.2) mmol.

[0022] Preferably, the preparation method of the sterile liquid dressing is that EGF, silicone rubber modified chitosan, epoxy-modified quaternary ammonium borate, polyacrylic resin IV, ethyl acetate, menthol, polyethylene glycol, purified water are added to a stirrer, stirred for 3-5 min at 20-30 DEG C, to obtain the sterile liquid dressing.

[0023] (III) Beneficial technical effects

[0024] The present application adds EGF, silicone rubber modified chitosan, epoxy-modified quaternary ammonium borate, polyacrylic resin IV, ethyl acetate, menthol, polyethylene glycol, purified water into a stirrer, stirs, to obtain the sterile liquid dressing.

[0025] In the stirring process, a large number of epoxy groups in the epoxy-modified quaternary ammonium borate will undergo ring-opening reaction with the phenolic hydroxyl group in the silicone rubber modified chitosan, cross-linking each other, better adsorbed on the surface of the skin, making the film-forming effect better, promoting the repair and antibacterial effect on the skin. The chitosan in the silicone rubber modified chitosan and the quaternary ammonium salt group in the epoxy-modified quaternary ammonium borate both have good antibacterial effect, and the quaternary ammonium salt substitution degree in the epoxy-modified quaternary ammonium borate is high, further improving the antibacterial effect. The silicone rubber has good biocompatibility and good adsorption capacity, can be used as a protective layer to reduce the direct contact of external bacteria on the skin. The boron element and magnolol structure in the sterile liquid dressing also have anti-inflammatory and antibacterial effects. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is the reaction formula of the epoxy-modified quaternary ammonium borate. DETAILED DESCRIPTION

[0027] Preparation of chitosan hydrochloride mixed solution: 0.3 g of chitosan hydrochloride was added to 15 ml of an ethanol / water (2 / 1, v / v) mixed solution to form a chitosan hydrochloride mixed solution.

[0028] Example 1

[0029] (1) 6.5 mmol of magnolol, 5 mmol of 3-mercaptopropionic acid were dissolved in 2 ml of dichloromethane under nitrogen protection, after stirring uniformly, 1 mmol of benzpinacol catalyst was continuously added, and irradiated with 352 nm ultraviolet light in a dark environment for 2 h, the power was 40 W, after the end, the product was purified by chromatography column to obtain carboxylated magnolol;

[0030] (2) 3 mmol of carboxylated magnolol, 0.3 mmol of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide salt were dissolved in 5 ml of ethanol solvent, stirred at room temperature for 25 min, then 0.3 mmol of N-hydroxysuccinimide was added, reacted in an ice water bath for 1 h, 10 ml of chitosan hydrochloride mixed solution was continuously added, the pH was controlled at 4 at room temperature, and reacted for 20 h, the product was centrifuged and washed with ethanol, and finally dialyzed, freeze-dried to obtain magnolol modified chitosan;

[0031] (3) 20 ml of methanol solvent, 0.12 mmol of polymerization inhibitor dibutylhydroxytoluene, 0.23 mmol of tetrahydrofuran solution of catalyst chloroplatinic acid were added to the reactor, stirred for 2 min, 2.1 mmol of magnolol modified chitosan and 1.9 mmol of silicone rubber were continuously added, ultrasonic dispersion for 30 min, reaction at 65°C for 4 h, cooling, centrifugation, washing to obtain silicone rubber modified chitosan;

[0032] (4) 4 mmol of boric acid and 8.56 mmol of 1,3-bis(dimethylamino)-2-propanol were added to 25 ml of acetone solvent, stirred and dispersed, reacted at 95°C for 6 h, after the reaction was completed, reduced pressure distillation, filtration and drying to obtain tertiary amine borate;

[0033] (5) 2 mmol of tertiary amine borate and 7 mmol of 3-chloropropene were added to 20 ml of N,N-dimethylformamide solvent, stirred and dispersed, reacted at 70°C for 10 h, after the end, reduced pressure distillation, filtration to obtain alkenyl quaternary ammonium borate;

[0034] (6) 8 mmol of alkenyl quaternary boronic acid was added to 20 ml of N,N-dimethylformamide solvent at 25°C, stirred uniformly, then 40 mmol of aqueous hydrogen peroxide solution was added, stirred for 3 h, after the reaction was completed, it was left to stand, distilled under reduced pressure, washed, and an epoxy-modified quaternary boronic acid was obtained;

[0035] (7) 0.001 g of EGF, 2 g of silicone rubber-modified chitosan, 1 g of epoxy-modified quaternary boronic acid, 8 g of polyacrylic resin IV, 3 g of ethyl acetate, 0.4 g of menthol, 5 g of polyethylene glycol, and 40 g of purified water were added to a stirrer, stirred for 3 min at 20°C, and a sterile liquid dressing was obtained.

[0036] Example 2

[0037] (1) 7 mmol of magnolol, 5 mmol of 3-mercaptopropionic acid were dissolved in 4 ml of dichloromethane under nitrogen protection, after uniform stirring, 1.5 mmol of benzoin dimethyl ether catalyst was continuously added, irradiated with 365 nm ultraviolet light in a dark environment for 4 h, the power was 40 W, after the end, the product was purified by chromatography column, and carboxylated magnolol was obtained;

[0038] (2) 3 mmol of carboxylated magnolol, 0.6 mmol of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide salt were dissolved in 7 ml of ethanol solvent, stirred at room temperature for 40 min, then 0.9 mmol of N-hydroxysuccinimide was added, reacted in an ice water bath for 2 h, 13 ml of chitosan hydrochloride mixture was continuously added, the pH was controlled at 5.8 at room temperature, and reacted for 24 h, the product was centrifuged and washed with ethanol, and finally dialyzed, freeze-dried to obtain magnolol-modified chitosan;

[0039] (3) 30 ml of methanol solvent, 0.14 mmol of polymerization inhibitor dibutylhydroxytoluene, and 0.27 mmol of tetrahydrofuran solution of catalyst chloroplatinic acid were added to the reactor, stirred for 4 min, 2.6 mmol of magnolol-modified chitosan and 2.2 mmol of silicone rubber were continuously added, ultrasonic dispersion was performed for 40 min, and reaction was performed at 80°C for 6 h, and after cooling, centrifugation and washing, silicone rubber-modified chitosan was obtained;

[0040] (4) 4 mmol of boric acid and 11.44 mmol of 1,3-bis(dimethylamino)-2-propanol were added to 35 ml of acetone solvent, stirred and dispersed, and reacted at 110°C for 8 h, after the reaction was completed, it was distilled under reduced pressure, filtered and dried, and a tertiary amine boronic acid was obtained;

[0041] (5) 2 mmol of tertiary amine boronic acid and 8.4 mmol of 3-chloropropene were added to 40 ml of N,N-dimethylformamide solvent, stirred and dispersed, and reacted at 85°C for 12 h. After the reaction was completed, distillation was performed under reduced pressure, and filtration was performed to obtain an enyl quaternary ammonium boronic acid;

[0042] (6) 12 mmol of enyl quaternary ammonium boronic acid was added to 35 ml of N,N-dimethylformamide solvent at 30°C, stirred and mixed, and then 55 mmol of an aqueous hydrogen peroxide solution was added thereto, stirred and reacted for 5 h. After the reaction was completed, standing was performed, distillation was performed under reduced pressure, and washing was performed to obtain an epoxy-modified quaternary ammonium boronic acid;

[0043] (7) 0.002 g of EGF, 3 g of silicone rubber-modified chitosan, 3 g of epoxy-modified quaternary ammonium boronic acid, 11 g of polyacrylic acid resin IV, 6 g of ethyl acetate, 0.6 g of menthol, 9 g of polyethylene glycol, and 60 g of purified water were added to a stirrer, stirred at 30°C for 5 min, and a sterile liquid dressing was obtained.

[0044] Example 3

[0045] (1) 6.8 mmol of magnolol, 5 mmol of 3-mercapto propionic acid, and 1.2 mmol of benzoin dimethyl ether catalyst were dissolved in 3 ml of dichloromethane under nitrogen protection, stirred and mixed, and then irradiated with ultraviolet light of 356 nm for 3 h in a dark environment at a power of 40 W. After the reaction was completed, the product was purified by a chromatographic column to obtain a carboxylated magnolol;

[0046] (2) 3 mmol of the carboxylated magnolol, 0.4 mmol of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide salt, and 0.6 mmol of N-hydroxysuccinimide were dissolved in 6 ml of an ethanol solvent, stirred at room temperature for 35 min, and then reacted in an ice water bath for 1 h. Then, 12 ml of a chitosan hydrochloride mixture was added, and the pH was controlled at 5.8 at room temperature. The reaction was performed for 22 h, the product was centrifuged and washed with ethanol, and then dialysis and lyophilization were performed to obtain a magnolol-modified chitosan;

[0047] (3) 25 ml of a methanol solvent, 0.13 mmol of a polymerization inhibitor, i.e., dibutylhydroxytoluene, and 0.25 mmol of a catalyst, i.e., chloroplatinic acid in a tetrahydrofuran solution, were added to a reactor, stirred for 3 min, and then 2.3 mmol of the magnolol-modified chitosan and 2.1 mmol of silicone rubber were added thereto, ultrasonically dispersed for 35 min, and reacted at 70°C for 5 h. After the reaction was completed, cooling, centrifugation, and washing were performed to obtain a silicone rubber-modified chitosan;

[0048] (4) 4 mmol of boric acid and 9.56 mmol of 1,3-bis(dimethylamino)-2-propanol were added to 30 ml of acetone solvent, stirred and dispersed, and reacted at 100°C for 7 h. After the reaction was completed, distillation was performed under reduced pressure, and filtration and drying were performed to obtain a tertiary amine-based boric acid;

[0049] (5) 2 mmol of the tertiary amine-based boric acid and 8.2 mmol of 3-chloropropene were added to 30 ml of N,N-dimethylformamide solvent, stirred and dispersed, and reacted at 76°C for 11 h. After the reaction was completed, distillation was performed under reduced pressure, and filtration was performed to obtain an alkenyl quaternary ammonium boric acid;

[0050] (6) 10 mmol of the alkenyl quaternary ammonium boric acid was added to 25 ml of N,N-dimethylformamide solvent at 28°C, stirred and mixed, and then 45 mmol of an aqueous hydrogen peroxide solution was added thereto, stirred and reacted for 4 h. After the reaction was completed, standing was performed, and distillation was performed under reduced pressure to obtain an epoxy-modified quaternary ammonium boric acid.

[0051] (7) 0.001 g of EGF, 2.5 g of silicone rubber-modified chitosan, 2 g of the epoxy-modified quaternary ammonium boric acid, 10 g of polyacrylic acid resin IV, 4 g of ethyl acetate, 0.5 g of menthol, 6 g of polyethylene glycol, and 50 g of purified water were added to a stirrer, stirred at 25°C for 4 min, and then a sterile liquid dressing was obtained.

[0052] Example 4

[0053] (1) 6.5 mmol of magnolol, 5 mmol of 3-mercaptopropionic acid, and 1 mmol of benzoin dimethyl ether catalyst were dissolved in 2 ml of dichloromethane under nitrogen protection, stirred and mixed, and then irradiated with ultraviolet light of 352 nm in a dark environment for 2 h at a power of 40 W. After the reaction was completed, the product was purified by a chromatographic column to obtain carboxylated magnolol.

[0054] (2) 3 mmol of the carboxylated magnolol, 0.3 mmol of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide salt, and 0.3 mmol of N-hydroxysuccinimide were dissolved in 5 ml of ethanol solvent, stirred at room temperature for 25 min, and then 10 ml of a chitosan hydrochloride mixture was added. The reaction was performed at room temperature for 20 h while controlling the pH to be 4. The product was centrifuged, washed with ethanol, and then subjected to dialysis and lyophilization to obtain magnolol-modified chitosan.

[0055] (3) 30 ml of methanol solvent, 0.14 mmol of polymerization inhibitor dibutyl hydroxytoluene, 0.27 mmol of catalyst chloroplatinic acid tetrahydrofuran solution were added into the reactor, stirred for 4 min, 2.6 mmol of magnolia officinalis phenol modified chitosan and 2.2 mmol of silicone rubber were continuously added, ultrasonic dispersion for 40 min, reaction at 80℃ for 6h, cooling, centrifugal, washing, to obtain silicone rubber modified chitosan;

[0056] (4) 4 mmol of boric acid and 11.44 mmol of 1,3-bis(dimethylamino)-2-propanol were added into 35 ml of acetone solvent, stirred and dispersed, reacted at 110℃ for 8h, after the reaction was completed, reduced pressure distillation, filtration and drying, to obtain tertiary amine boronic acid;

[0057] (5) 2 mmol of tertiary amine boronic acid and 8.2 mmol of 3-chloropropene were added into 30 ml of N,N-dimethylformamide solvent, stirred and dispersed, reacted at 76℃ for 11h, after the reaction was completed, reduced pressure distillation, filtration, to obtain alkenyl quaternary ammonium boronic acid;

[0058] (6) 10 mmol of alkenyl quaternary ammonium boronic acid was added into 25 ml of N,N-dimethylformamide solvent at 28℃, stirred uniformly, then 45 mmol of hydrogen peroxide aqueous solution was added, stirred and reacted for 4h, after the reaction was completed, standing, reduced pressure distillation, washing, to obtain epoxy modified quaternary ammonium boronic acid;

[0059] (7) 0.002 g of EGF, 2.5 g of silicone rubber modified chitosan, 2 g of epoxy modified quaternary ammonium boronic acid, 10 g of polyacrylic acid resin IV, 4 g of ethyl acetate, 0.5 g of menthol, 6 g of polyethylene glycol, 50 g of purified water were added into a stirrer, stirred at 25℃ for 4 min, to obtain a sterile liquid dressing.

[0060] Comparative Example 1

[0061] The difference between this comparative example and Example 4 is that no silicone rubber modified chitosan is added.

[0062] Comparative Example 2

[0063] The difference between this comparative example and Example 4 is that no epoxy modified quaternary ammonium boronic acid is added.

[0064] The sterile liquid dressing was dissolved and cast into a film to make a thin piece with a radius of 1 cm; then the bacteria were moved into a sterile culture medium with a loop to culture, to make a bacterial suspension with a concentration of 106CFU / mL, then 0.5 mL of the bacterial suspension was added dropwise into a culture dish containing beef extract peptone medium, shaken uniformly, then the thin piece was added, and cultured in a constant temperature incubator, and the diameter of the inhibition zone was measured after 48h of culture.

[0065] Table 1: Anti-bacterial test.

[0066] Item E. coli (mm) S. aureus (mm) Example 1 15.2 15.8 Example 2 17.3 17.4 Example 3 15.4 16.7 Example 4 15.6 15.2 Comparative Example 1 12.1 11.3 Comparative Example 2 12.3 13.5

[0067] From Table 1, it can be seen that the sterile liquid dressing examples 1-4 of the present application have better anti-bacterial effect compared to comparative examples 1-2.

[0068] At 15-20℃, 0.2ml of the liquid dressing of examples 1-4 and comparative examples 1-2 were respectively sprayed on a flat dish (90mm) uniformly to an area of about 2cm 2 , and the time for drying and solidifying into a film was recorded. The experiment was repeated twice, and the average of the three experiments was taken. The results are shown in Table 2.

[0069] Table 2: Film forming time.

[0070] Item Time to film formation (min) Example 1 3 min Example 2 2 min 15 s Example 3 2 min 48 s Example 4 3 min 14 s Comparative Example 1 4 min 25 s Comparative Example 2 4 min 34 s

[0071] From Table 2, it can be seen that the sterile liquid dressing examples 1-4 of the present application have better film forming effect compared to comparative examples 1-2.

[0072] The liquid dressing of examples 1-4 and comparative examples 1-2 of the present application were taken as experimental groups, and were respectively applied to the surface of the wound skin (2cm 2 ) of 10 SD rats (half male and half female, body weight 148.2±12.5g) each with 1ml. The solidification film forming time and repair time were observed. The results are shown in Table 3.

[0073] Table 3: Repair time.

[0074] Item Repair time (d) Example 1 2-4 Example 2 1-2 Example 3 2-3 Example 4 2-3 Comparative Example 1 4-6 Comparative Example 2 4-5

[0075] From Table 3, it can be seen that the sterile liquid dressing examples 1-4 of the present application have better repair effect compared to comparative examples 1-2.

[0076] The preferred embodiments of the present application disclosed above are only used to help explain the present application. The preferred embodiments do not describe all the details, and do not limit the present application to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of the present application. The present application selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present application, so that those skilled in the art can well understand and utilize the present application. The present application is limited only by the claims and their full scope and equivalents.

Claims

1. A sterile liquid dressing, characterized in that, It comprises the following components by weight: 0.001-0.002 parts by weight of EGF, 2-3 parts by weight of silicone rubber modified chitosan, 1-3 parts by weight of epoxy-modified quaternary ammonium boric acid, 8-11 parts by weight of polyacrylic acid resin IV, 3-6 parts by weight of ethyl acetate, 0.4-0.6 parts by weight of menthol, 5-9 parts by weight of polyethylene glycol, and 40-60 parts by weight of purified water; The preparation method of the silicone rubber modified chitosan is as follows: Step 1: Dissolve magnolol and 3-mercaptopropionic acid in dichloromethane under nitrogen protection. After stirring evenly, add benzoin dimethyl ether catalyst. Irradiate with 352-365nm ultraviolet light for 2-4 hours in the dark at a power of 40W. After the irradiation, purify the product with a chromatographic column to obtain carboxylated magnolol. Step 2: Dissolve carboxylated magnolol and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide salt in ethanol solvent and stir at room temperature for 25-40 min. Then add N-hydroxysuccinimide and react in an ice-water bath for 1-2 h. Continue to add 10-13 ml of chitosan hydrochloride mixture and control the pH at room temperature to 4-5.

8. React for 20-24 h. Centrifuge the product and wash it with ethanol. Finally, dialyze and freeze dry to obtain magnolol-modified chitosan. Step 3: Add methanol solvent, 0.12-0.14 mmol of polymerization inhibitor dibutylhydroxytoluene, and 0.23-0.27 mmol of tetrahydrofuran solution of chloroplatinic acid catalyst to the reactor, stir for 2-4 min, then add 2.1-2.6 mmol of magnolol-modified chitosan and 1.9-2.2 mmol of silicone rubber, sonicate for 30-40 min, react at 65-80℃ for 4-6 h, cool, centrifuge, and wash to obtain silicone rubber-modified chitosan; The preparation method of the epoxy-modified quaternary ammonium boric acid is as follows: S1. Boric acid and 1,3-bis(dimethylamino)-2-propanol were added to acetone solvent, stirred and dispersed, and reacted at 95-110℃ for 6-8h. After the reaction was completed, the mixture was distilled under reduced pressure, filtered and dried to obtain tertiary aminoboric acid. S2. Add tertiary aminoboronic acid and 3-chloropropene to N,N-dimethylformamide solvent, stir and disperse, react at 70-85℃ for 10-12h, after which distill under reduced pressure and filter to obtain alkenyl quaternized boronic acid; S3. At 25-30℃, 8-12 mmol of alkenyl quaternized boric acid was added to N,N-dimethylformamide solvent and stirred until homogeneous. Then, an aqueous solution containing 40-55 mmol of hydrogen peroxide was added and the mixture was stirred for 3-5 hours. After the reaction was completed, the mixture was allowed to stand, then distilled under reduced pressure and washed to obtain epoxy-modified quaternized boric acid.

2. The sterile liquid dressing according to claim 1, characterized in that, In step one, the molar ratio of magnolol, 3-mercaptopropionic acid, and benzoin dimethyl ether catalyst is (1.3-1.4) mmol:1 mmol:(0.2-0.3) mmol.

3. The sterile liquid dressing according to claim 1, characterized in that, In step two, the molar ratio of carboxylated magnolol, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide salt, and N-hydroxysuccinimide is 1 mmol:(0.1-0.2) mmol:(0.1-0.3) mmol.

4. The sterile liquid dressing according to claim 1, characterized in that, The molar ratio of boric acid and 1,3-bis(dimethylamino)-2-propanol in S1 is 1 mmol:(2.14-2.86) mmol.

5. The sterile liquid dressing according to claim 1, characterized in that, The molar ratio of tertiary aminoboronic acid and 3-chloropropene in S2 is 1 mmol:(3.5-4.2) mmol.

6. A method for preparing a sterile liquid dressing as described in any one of claims 1-5, characterized in that, The sterile liquid dressing is prepared by adding EGF, silicone rubber modified chitosan, epoxy-modified quaternary ammonium boric acid, polyacrylic acid resin IV, ethyl acetate, menthol, polyethylene glycol, and purified water into a stirrer and stirring at 20-30℃ for 3-5 minutes to obtain the sterile liquid dressing.

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