A composite fiber antibacterial bandage and its preparation method

Abstract

The present invention relates to the technical field of bandages, and specifically to a composite fiber antibacterial bandage and a preparation method thereof. An antibacterial impregnating solution is obtained by physical cross-linking using the characteristics that quaternary ammonium salt chitosan dissolves in water to carry a positive charge and sodium alginate dissolves in water to carry a negative charge; using the characteristic that polyethylene glycol can effectively prevent the growth of bacteria and molds, polyethylene glycol is connected to the surface of polydopamine nanospheres by a covalent bonding method to form a polymer molecular brush, obtaining an antibacterial impregnating solution; cotton fibers and polyester fibers are respectively impregnated into the antibacterial impregnating solution and the antibacterial impregnating solution to obtain antibacterial fibers and antibacterial fibers, and a bandage with both antibacterial adhesion prevention and antibacterial functions is prepared by co-spinning the antibacterial fibers and the antibacterial fibers. The prepared bandage has a good antibacterial effect and effectively improves the persistence of antibacterial.

Description

Technical Field

[0001] The present invention relates to the technical field of bandages, and specifically relates to a composite fiber antibacterial bandage and a preparation method thereof. Background Art

[0002] Bandages are usually applied in first aid and postoperative wound healing. It can create a clean and moist environment for the wound, provide physical support and wound protection, prevent bacterial infection, and promote wound healing. In the environment where people live, floating bacteria and fungi are everywhere and can non-specifically adhere to the interface to form biofouling. Especially in the field of biomedicine, when these biomedical materials are used for a long time, due to the non-specific adhesion of proteins and bacteria, it will lead to microbial infection, which will not only prolong the wound healing time, increase the economic burden and pain of patients, but even lead to death. Usually, bacteria floating in the air or liquid can attach to the surfaces of various materials they can contact through physical adsorption, causing the initial adhesion of bacteria; over time, the bacteria settled on the material surface resume growth and multiply continuously; when the bacterial density reaches a certain level, the bacteria begin to secrete extracellular polymers continuously to form a biofilm matrix, and finally form a mature biofilm. At the same time, some detached biofilms and a small amount of released planktonic bacteria diffuse to new sites to restart the formation of biofilms. Once the biofilm is formed, it indicates that the bacteria have firmly adhered to the material surface and can protect the bacteria from the influence of environmental changes, preventing the killing and phagocytosis by antibiotics and the body's immune system. Therefore, it is necessary to study various methods to prevent the adhesion and reproduction of bacteria, reduce bacterial adhesion from the source, and thus reduce the formation of biofilms.

[0003] Chinese Patent with Publication No. CN117618624B discloses a biodegradable medical polymer bandage and a preparation method thereof, and prepares an antibacterial and skin-friendly polylactic acid. The antibacterial and skin-friendly polylactic acid is prepared by reacting carboxyl-modified chitosan, epoxy quaternary ammonium salt and hydrophilic-modified polylactic acid. Under the action of carboxyl-modified chitosan, the mechanical properties and hydrophilic properties of hydrophilic-modified polylactic acid are improved, the number of active groups increases, the cell adhesion ability is improved, and the application range of PLA in the medical and health field is expanded. The introduction of carboxyl-modified chitosan and epoxy quaternary ammonium salt improves the antibacterial and antifungal properties of hydrophilic-modified polylactic acid, avoids bacterial infection of the wound, and has excellent antibacterial and antiviral effects. Chinese Patent with Publication No. CN116115815B discloses an antibacterial medical bandage and a preparation method thereof, which uses a medical non-woven fabric with good air permeability as the base material, impregnates it in a thermoplastic polyurethane elastomer rubber impregnating solution, then coats an uncured thermoplastic polyurethane elastomer rubber film-forming solution on the non-woven fabric with a scraper, and then evenly coats a SiO2-ZnO nanoparticle dispersion solution, and obtains it by pressurized drying and curing.

[0004] However, the above research focuses on how to improve the antibacterial performance. However, the dead microorganisms will form a biofilm on the fabric surface, hindering the contact between the antibacterial agent and the microorganisms and leading to a decline in the antibacterial performance. Therefore, the problem that the biofilm formed by the adhesion of dead bacteria will cause a decline in the performance of antibacterial materials has become the focus of attention. Summary of the Invention

[0005] Aiming at the deficiencies existing in the prior art, the present invention provides a composite fiber antibacterial bandage and its preparation method, which is obtained by mixing and spinning antibacterial fibers and antibacterial-proof fibers, followed by weaving and then cross-linking with a calcium chloride solution. The prepared bandage has good antibacterial effects.

[0006] In order to achieve the above objectives, the technical solutions adopted by the present invention are as follows:

[0007] A preparation method of a composite fiber antibacterial bandage, comprising the following steps:

[0008] S1. Preparation of antibacterial fibers: Dissolve sodium alginate in water, add quaternary ammonium chitosan, react for 12 - 18 h under magnetic stirring to obtain an antibacterial impregnating solution. Raise the temperature to 30 - 45 °C, add cotton fibers thereto to make them completely immersed in the antibacterial impregnating solution, place for 2 - 4 h for impregnation, and after the impregnation is completed, take out and dry to obtain antibacterial fibers; the drying conditions are: drying in a vacuum drying oven at 35 - 45 °C for 2 - 4 h;

[0009] Further, the preparation process of quaternary ammonium chitosan is as follows: Using isopropanol as a solvent, add chitosan, heat and mix evenly, then adjust the pH of the solution to 8 - 9, and then add an aqueous solution of 2,3-epoxypropyltrimethylammonium chloride, raise the temperature to 75 - 85 °C and react for 25 - 30 h. After the reaction is completed, obtain quaternary ammonium chitosan through dialysis, filtration, and freeze-drying; the dosage of 2,3-epoxypropyltrimethylammonium chloride in the aqueous solution of 2,3-epoxypropyltrimethylammonium chloride is 0.06 - 0.1 g / mL; the mass ratio of isopropanol, chitosan, and 2,3-epoxypropyltrimethylammonium chloride is 28 - 32:1:4 - 8;

[0010] Chitosan is widely present in the shells of marine arthropods, the exoskeletons of insects, the cell membranes of fungi and algae, the shells and skeletons of mollusks, and the cell walls of higher plants. It is a non-toxic, biodegradable, and biocompatible cationic polysaccharide with broad-spectrum antibacterial effects and can inhibit the growth of various bacteria and fungi. Chitosan can damage the cell membranes and cell walls of microorganisms, resulting in the outflow of intercellular electrolytes and causing the death of microorganisms. It can also bind to DNA in the cell nuclei of microorganisms, thereby inhibiting the synthesis of RNA and proteins. In addition, chitosan has the ability to promote cell regeneration and helps the rapid healing of wounds. However, under alkaline or neutral conditions, chitosan has poor solubility, which limits its application. Quaternary ammonium compounds, as antibacterial agents, have low toxicity and low irritation and are suitable for antibacterial disinfection of the skin, mucous membranes, and wounds. Quaternary ammonium salts have broad-spectrum bactericidal properties and can kill a variety of bacteria, fungi, and lipophilic viruses. By adsorbing to the surface of the bacteria, the hydrophobic groups insert into the lipid layer, changing the permeability of the cell membrane, destroying the membrane structure, resulting in the leakage of intracellular substances, and ultimately inhibiting the cell metabolism process, leading to the death of the bacteria. Therefore, in the present invention, quaternary ammonium salts are used to modify chitosan to obtain quaternary ammonium salt chitosan as the main antibacterial agent, further enhancing the antibacterial effect. Sodium alginate is a linear high-molecular natural polysaccharide extracted from brown algae, with good adhesion performance and stability. At the same time, sodium alginate has good moisture retention performance, can maintain a moist environment of the wound surface, promote cell proliferation and tissue regeneration, and accelerate wound healing. It also has certain antibacterial and anti-inflammatory effects, reduces the risk of bacterial infection, and alleviates the inflammatory reaction around the wound surface. The quaternary ammonium salt chitosan molecule contains many amino groups and is positively charged after dissolving in water, while sodium alginate is negatively charged after dissolving in water. By using the characteristics of the positive charge of quaternary ammonium salt chitosan and the negative charge of sodium alginate for physical cross-linking, the binding strength is increased and it is conducive to dispersion. Cotton textiles have good air permeability and moisture absorption capacity and can play a role of soft comfort and heat insulation in daily applications. However, they lack antibacterial groups themselves and do not have antibacterial ability, and are prone to bacterial growth in applications. Therefore, in this step, quaternary ammonium salt chitosan is used as an antibacterial agent to combine with sodium alginate and impregnate cotton fibers to obtain antibacterial fibers with a surface-coated antibacterial agent;

[0011] S2. Preparation of antibacterial fibers: Add polydopamine nanospheres to Tris buffer solution, ultrasonically disperse evenly, then add diaminopolyethylene glycol, and react under magnetic stirring for 25 - 30 h to obtain an antibacterial impregnating solution. Add polyester fibers to it to make them completely immersed in the antibacterial impregnating solution, place for 2 - 4 h for impregnation, and after the impregnation is completed, take out and dry to obtain antibacterial fibers; the drying conditions are: drying in a vacuum drying oven at 35 - 45 °C for 2 - 4 h; the ultrasonic dispersion conditions are: ultrasonic dispersion at a power of 500 W for 6 - 10 min;

[0012] Further, the preparation process of the polydopamine nanospheres is as follows: Add absolute ethanol, ammonia water and water into a reactor. After mixing evenly, add dopamine hydrochloride, and react at room temperature for 28 - 36 h, then centrifuge and separate. After washing, polydopamine nanospheres are obtained; the volume ratio of absolute ethanol, ammonia water and water is 3.5 - 5.5:0.1:8.2 - 12.5; the dosage of dopamine hydrochloride in water is 2.2 - 3.0 mg / mL;

[0013] After an antibacterial product is used for a period of time, the dead microorganisms will form a biofilm on the surface of the product, which hinders the contact between the antibacterial agent and the microorganisms, resulting in a gradual weakening of the antibacterial performance of the product. Moreover, the biofilm will provide new sites for the adhesion of subsequent bacteria, further reducing the antibacterial effect of the product. To address this problem, antibacterial fibers and antibacterial adhesion - preventing fibers are prepared while introducing antibacterial fibers in the present invention. The polydopamine nanospheres are nanoparticles prepared from polydopamine, which have dopamine functional groups, with super - strong adhesion performance, good biocompatibility and versatility; the dopamine functional groups on the surface of the polydopamine nanospheres can interact with bacteria and microorganisms, having the potential for antibacterial and anti - biofouling; the molecular structure of polyethylene glycol can change the surface energy state, reducing the surface attraction of the object, so that dirt is not easily adhered. Therefore, polyethylene glycol can effectively prevent the growth of bacteria and molds. At the same time, polyethylene glycol is a hydrophilic substance with good moisturizing effects, and can also promote local blood circulation, stimulate collagen regeneration, and play a certain role in repairing damaged skin. Therefore, in this step, polyethylene glycol is connected to the surface of the polydopamine nanospheres by a covalent bonding method to form a polymer molecular brush, which can effectively prevent the adhesion of bacteria and proteins. The polyester fiber has excellent wear resistance and shape retention, high strength and elastic recovery ability, but its moisture absorption is poor and its air permeability is not good; by immersing it in an antibacterial impregnating solution containing polydopamine nanospheres modified with diaminopolyethylenediamine, its hydrophilicity can be improved. At the same time, by co - spinning with cotton fibers with antibacterial properties, the moisture absorption and air permeability of the bandage are further improved, and certain strength and elasticity are given to the bandage.

[0014] S3. Mix and spin - draw the antibacterial fibers and the antibacterial adhesion - preventing fibers to obtain an antibacterial bandage base material. Immerse it in water, add concentrated ammonia water and quickly stir and mix evenly. Let it stand for 25 - 30 h, then add a calcium chloride solution for cross - linking. After 3 - 5 h, suck out the calcium chloride solution, soak and wash it with water, change the water every 2 - 4 h, and change the water 3 - 5 times, then take it out and dry it to obtain the composite fiber antibacterial bandage; the drying conditions are: drying in a vacuum drying oven at 40 - 50 °C for 4 - 8 h;

[0015] In this step, through Ca +Crosslink the sodium alginate coated on the antibacterial fiber and the polydopamine nanospheres coated on the antibacterial fiber. At the same time, a large number of hydrogen bonds are generated between the large number of hydroxyl groups on the surface of sodium alginate and the hydroxyl and amino groups on the surface of polydopamine nanospheres, resulting in intermolecular attraction, forming a macromolecular network structure on the surface of the prepared antibacterial bandage, further enhancing the binding strength between the polymer and the fiber, and improving the stability of the prepared bandage.

[0016] The present invention has the following beneficial effects:

[0017] In the present invention, a bandage with both antibacterial adhesion prevention and antibacterial functions is prepared by co-spinning antibacterial fibers and antibacterial fibers. Quaternary ammonium salt modified chitosan is used as the main antibacterial agent, and an antibacterial impregnating solution is obtained by physical crosslinking using the characteristics that quaternary ammonium salt chitosan is positively charged when dissolved in water and sodium alginate is negatively charged when dissolved in water. Antibacterial fibers are obtained by impregnating cotton fibers in the antibacterial impregnating solution. Utilizing the characteristic that polyethylene glycol can effectively prevent the growth of bacteria and molds, polyethylene glycol is connected to the surface of polydopamine nanospheres by a covalent bonding method to form a polymer molecular brush, obtaining an antibacterial impregnating solution, and then polyester fibers are impregnated in the antibacterial impregnating solution to obtain antibacterial fibers. Finally, through Ca + Crosslink the sodium alginate coated on the antibacterial fiber and the polydopamine nanospheres coated on the antibacterial fiber, form a macromolecular network structure on the surface of the prepared antibacterial bandage, further enhance the binding strength between the polymer and the fiber, so that the prepared bandage has good and persistent antibacterial properties while also endowing the bandage with certain strength and elasticity. Detailed implementation manners

[0018] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0019] The sodium alginate (AR) used in the present invention was purchased from Chengdu Shuobo Research and Innovation Technology Co., Ltd., the cotton fibers were purchased from Dezhou Caishihe Textile Co., Ltd., the polyester fibers were purchased from Younijike (Shanghai) Trading Co., Ltd. (UNIIKA, Japan), isopropanol, 2,3-epoxypropyltrimethylammonium chloride, Tris buffer solution, diaminopolyethylene glycol, dopamine hydrochloride, absolute ethanol, ammonia water (7.5% v / v), calcium chloride were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. (China), chitosan was purchased from Shanghai Macklin Biochemical Technology Co., Ltd. (China), and concentrated ammonia water was purchased from Tianjin Damao Chemical Reagent Factory. All reagents were commercially available.

[0020] Example 1

[0021] A preparation method of a composite fiber antibacterial bandage, comprising the following steps:

[0022] S1. Preparation of antibacterial fibers: Dissolve 2 parts by weight of sodium alginate in 185 parts by weight of deionized water, then add 3.5 parts by weight of quaternary ammonium chitosan. React for 16 h under magnetic stirring to obtain an antibacterial impregnating solution. Raise the temperature to 40 °C, add 85 parts by weight of cotton fibers thereto to completely immerse them in the antibacterial impregnating solution, place for 3 h for impregnation, and after the impregnation is completed, take out and dry to obtain antibacterial fibers; the drying conditions are: drying at 40 °C in a vacuum drying oven for 3 h;

[0023] Among them, the preparation process of quaternary ammonium chitosan is as follows: Using isopropanol as a solvent, add chitosan, heat to 70 °C and mix for 6 h, then adjust the pH of the solution to 8 - 9 with 1% NaOH solution, then add an aqueous solution of 2,3-epoxypropyltrimethylammonium chloride, raise the temperature to 80 °C and react for 28 h. After the reaction is completed, dialyze for 2 days to remove the unreacted 2,3-epoxypropyltrimethylammonium chloride, and obtain quaternary ammonium chitosan after filtration and freeze-drying; the dosage of 2,3-epoxypropyltrimethylammonium chloride in the aqueous solution of 2,3-epoxypropyltrimethylammonium chloride is 0.08 g / mL; the mass ratio of isopropanol, chitosan and 2,3-epoxypropyltrimethylammonium chloride is 30:1:6;

[0024] S2. Preparation of antibacterial fibers: Add 1.2 parts by weight of polydopamine nanospheres to 285 parts by weight of Tris buffer solution with a pH of 8.0, ultrasonically disperse evenly, then add 2.4 parts by weight of diaminopolyethylene glycol, react for 28 h under magnetic stirring to obtain an antibacterial impregnating solution, add 95 parts by weight of polyester fibers thereto to completely immerse them in the antibacterial impregnating solution, place for 3 h for impregnation, and after the impregnation is completed, take out and dry to obtain antibacterial fibers; among them, the drying conditions are: drying at 40 °C in a vacuum drying oven for 3 h; the conditions for ultrasonic dispersion are: ultrasonic dispersion at a power of 500 W for 8 min;

[0025] Among them, the preparation process of polydopamine nanospheres is as follows: Add absolute ethanol, ammonia water and deionized water to a reactor, mix evenly, then add dopamine hydrochloride, react at room temperature for 32 h and then centrifuge, and obtain polydopamine nanospheres after repeatedly washing with deionized water until the color of the supernatant after washing is close to that of deionized water; the volume ratio of absolute ethanol, ammonia water and deionized water is 4.5:0.1:11.2; the dosage of dopamine hydrochloride in deionized water is 2.5 mg / mL;

[0026] S3. Mix and spin the antibacterial fiber and the bacteria-proof fiber to obtain the base material of the antibacterial bandage. Immerse it in 150 parts by weight of deionized water, add 7.2 parts by weight of concentrated ammonia water, and quickly stir and mix evenly. After standing for 28 h, add 116 parts by weight of 5wt% calcium chloride solution for cross-linking. After 4 h, suck out the calcium chloride solution, soak and wash it with water, change the water every 3 h, and take it out and dry it after changing the water 4 times to obtain the composite fiber antibacterial bandage; the drying conditions are: drying in a vacuum drying oven at 45 °C for 6 h.

[0027] Example 2

[0028] This example is different from Example 1 as follows:

[0029] In step S1, dissolve 1.2 parts by weight of sodium alginate in 120 parts by weight of deionized water, add 2.2 parts by weight of quaternary ammonium chitosan, and react for 12 h under magnetic stirring to obtain the antibacterial impregnating solution. Raise the temperature to 30 °C, add 55 parts by weight of cotton fiber to it to make it completely immersed in the antibacterial impregnating solution, and place it for 2 h for impregnation. After the impregnation is completed, take it out and dry it to obtain the antibacterial fiber; the drying conditions are: drying in a vacuum drying oven at 35 °C for 2 h; in the preparation process of quaternary ammonium chitosan, after adding the aqueous solution of 2,3-epoxypropyltrimethylammonium chloride, raise the temperature to 75 °C and react for 25 h. The dosage of 2,3-epoxypropyltrimethylammonium chloride in the aqueous solution of 2,3-epoxypropyltrimethylammonium chloride is 0.06 g / mL; the mass ratio of isopropanol, chitosan and 2,3-epoxypropyltrimethylammonium chloride is 28:1:4;

[0030] In step S2, add 0.75 part by weight of polydopamine nanospheres to 175 parts by weight of Tris buffer solution with a pH of 8.5, ultrasonically disperse it evenly, then add 1.5 parts by weight of diaminopolyethylene glycol, and react for 25 h under magnetic stirring to obtain the bacteria-proof impregnating solution. Add 60 parts by weight of polyester fiber to it to make it completely immersed in the bacteria-proof impregnating solution, and place it for 2 h for impregnation. After the impregnation is completed, take it out and dry it to obtain the bacteria-proof fiber; the drying conditions are: drying in a vacuum drying oven at 35 °C for 2 h; the conditions for ultrasonic dispersion are: ultrasonic for 6 min at a power of 500 W; in the preparation process of polydopamine nanospheres, after adding dopamine hydrochloride, react at room temperature for 28 h. The volume ratio of absolute ethanol, ammonia water and water is 3.5:0.1:8.2; the dosage of dopamine hydrochloride in water is 2.2 mg / mL;

[0031] In step S3, the obtained antibacterial bandage base material is immersed in 95 parts by weight of deionized water, 4.5 parts by weight of concentrated ammonia water is added, and then it is quickly stirred and mixed evenly. After standing for 25 h, 72 parts by weight of 5 wt% calcium chloride solution is added for crosslinking. After 3 h, the calcium chloride solution is sucked off, and it is soaked and washed with water, changing the water every 2 h. After changing the water 3 times, it is taken out and dried to obtain the composite fiber antibacterial bandage; the drying conditions are: drying in a vacuum drying oven at 40 °C for 4 h.

[0032] Example 3

[0033] Compared with Example 1, this example has the following differences:

[0034] In step S1, 3 parts by weight of sodium alginate is dissolved in 280 parts by weight of deionized water, 5.5 parts by weight of quaternary ammonium salt chitosan is added, and it reacts for 18 h under magnetic stirring to obtain the antibacterial impregnating solution. The temperature is raised to 45 °C, 125 parts by weight of cotton fiber is added thereto to completely immerse it in the antibacterial impregnating solution, and it is left for 4 h for impregnation. After the impregnation is completed, it is taken out and dried to obtain the antibacterial fiber; the drying conditions are: drying in a vacuum drying oven at 45 °C for 4 h; in the preparation process of the quaternary ammonium salt chitosan, after adding the aqueous solution of 2,3-epoxypropyltrimethylammonium chloride, the temperature is raised to 85 °C and reacted for 30 h. The dosage of 2,3-epoxypropyltrimethylammonium chloride in the aqueous solution of 2,3-epoxypropyltrimethylammonium chloride is 0.1 g / mL; the mass ratio of isopropanol, chitosan and 2,3-epoxypropyltrimethylammonium chloride is 32:1:8;

[0035] In step S2, 1.8 parts by weight of polydopamine nanospheres are added to 425 parts by weight of Tris buffer solution with a pH of 8.5, ultrasonically dispersed evenly, 3.6 parts by weight of diaminopolyethylene glycol is added, and it reacts for 30 h under magnetic stirring to obtain the antibacterial impregnating solution. 145 parts by weight of polyester fiber is added thereto to completely immerse it in the antibacterial impregnating solution, and it is left for 4 h for impregnation. After the impregnation is completed, it is taken out and dried to obtain the antibacterial fiber; the drying conditions are: drying in a vacuum drying oven at 45 °C for 4 h; the conditions of ultrasonic dispersion are: ultrasonicating at a power of 500 W for 10 min; in the preparation process of the polydopamine nanospheres, after adding dopamine hydrochloride, it reacts at room temperature for 36 h. The volume ratio of anhydrous ethanol, ammonia water and water is 5.5:0.1:12.5; the dosage of dopamine hydrochloride in water is 3.0 mg / mL;

[0036] In step S3, the obtained antibacterial bandage base material is immersed in 240 parts by weight of deionized water, 12 parts by weight of concentrated ammonia water is added, and then it is quickly stirred and mixed evenly. After standing for 30 h, 175 parts by weight of 5 wt% calcium chloride solution is added for crosslinking. After 5 h, the calcium chloride solution is sucked off, and it is soaked and washed with water, changing the water every 4 h. After changing the water 5 times, it is taken out and dried to obtain the composite fiber antibacterial bandage; the drying conditions are: drying in a vacuum drying oven at 50 °C for 8 h.

[0037] Comparative Example 1

[0038] Compared with Example 1, when preparing the antibacterial fiber, the quaternary ammonium salt chitosan was replaced with chitosan, as follows:

[0039] S1. Preparation of antibacterial fiber: Dissolve 2 parts by weight of sodium alginate in 185 parts by weight of deionized water, then add 3.5 parts by weight of chitosan, and react for 16 h under magnetic stirring to obtain an antibacterial impregnating solution. Raise the temperature to 40 °C, add 85 parts by weight of cotton fiber to it to make it completely immersed in the antibacterial impregnating solution, place it for 3 h for impregnation, and take it out and dry it after impregnation to obtain antibacterial fiber; the drying conditions are: drying in a vacuum drying oven at 40 °C for 3 h.

[0040] The rest refers to Example 1.

[0041] Comparative Example 2

[0042] Compared with Example 1, when preparing the antibacterial fiber, diaminopolyethylene glycol was not added, as follows:

[0043] S2. Preparation of antibacterial fiber: Add 1.2 parts by weight of polydopamine nanospheres to 285 parts by weight of deionized water, ultrasonically disperse evenly, and react for 28 h under magnetic stirring to obtain an antibacterial impregnating solution. Add 95 parts by weight of polyester fiber to it to make it completely immersed in the antibacterial impregnating solution, place it for 3 h for impregnation, and take it out and dry it after impregnation to obtain antibacterial fiber; the drying conditions are: drying in a vacuum drying oven at 40 °C for 3 h; the conditions for ultrasonic dispersion are: ultrasonic dispersion at a power of 500 W for 8 min.

[0044] The rest refers to Example 1.

[0045] Comparative Example 3

[0046] Compared with Example 1, the cross-linking reaction was not carried out in step S3, as follows:

[0047] S3. Mix and spin the antibacterial fiber and the antibacterial fiber to obtain an antibacterial bandage base material, and place it in a vacuum drying oven to dry at 45 °C for 6 h to obtain a composite antibacterial bandage.

[0048] The rest refers to Example 1.

[0049] Comparative Example 4

[0050] Compared with Example 1, the composite fiber bandage was directly obtained by blending cotton fiber and polyester fiber, as follows:

[0051] The preparation process of a composite fiber bandage is as follows: Mix cotton fibers and polyester fibers for spinning and weaving to obtain a bandage base material, and place it in a vacuum drying oven to dry at 45°C for 6 hours to obtain the composite fiber bandage.

[0052] Related tests:

[0053] Perform performance tests on the bandages prepared in Examples 1 to 3 and Comparative Examples 1 to 4.

[0054] Tensile strength test: Under the conditions of 20°C and a relative humidity of 65%, the sample size is 100 mm in length, 20 mm in width, and 4 mm in thickness. Use an electronic universal material testing machine to test the tensile properties of the sample, with a clamping distance of 5 mm and a tensile speed of 50 mm / min; each sample is tested 5 times and the average value is taken.

[0055] In vitro cytotoxicity test: Refer to the experimental method of ISO10993-5 "Biological evaluation of medical devices - Part 5: Tests for in vitro cytotoxicity" for testing: Passage the L-929 (ATCC CL-1) mouse fibroblasts 5 times, inoculate them in a 96-well plate, add Dulbecco's modified Eagle medium, transfer them to a 5% carbon dioxide cell culture incubator, incubate at 37°C for 24 hours, add 50 μL of phenazine methosulfate solution after 8 hours of incubation, incubate at 37°C in the dark for 4 hours, and use an enzyme-linked immunosorbent assay (ELISA) reader to measure the optical density at 490 nm to evaluate cell proliferation. When the cell survival rate ≥ 70%, the sample can be judged to be safe and non-toxic.

[0056] The test results are shown in Table 1.

[0057] Table 1 Test results of tensile strength and in vitro cell survival rate

[0058]

[0059]

[0060] Antibacterial property test: After washing the bandages prepared in Examples 1 to 3 and Comparative Examples 1 to 4 0 times, 5 times, and 10 times respectively, test the antibacterial property according to the standard of GB / T 20944.2-2007. The test results are shown in Table 2.

[0061] Table 2 Test results of antibacterial property

[0062]

[0063] The test results in Table 1 and Table 2 show that the test data of Examples 1 to 3 are generally better than those of Comparative Examples 1 to 4, and especially the performance of Example 1 is the best. From the tensile strength test results of Example 1, Comparative Example 3 (without cross-linking reaction), and Comparative Example 4 (directly woven from cotton fibers and polyester fibers), it can be seen that after Ca +After cross-linking the sodium alginate coated on the antibacterial fiber and the polydopamine nanospheres coated on the antibacterial fiber, its tensile strength has been improved to a certain extent. This is because a macromolecular network structure is formed on the surface of the bandage through the cross-linking reaction, further improving the tensile strength of the bandage. From the results of in vitro cytotoxicity tests, it can be seen that the bandage prepared by the present invention has good biosafety. From the results of antibacterial performance tests, it can be seen that the bandage prepared in Example 1 still has good antibacterial performance after multiple washes. This is because the antibacterial agent is combined with the bandage in various ways such as covalent bonds, hydrogen bonds, and electrostatic interactions, which can effectively improve the persistence of antibacterial activity.

[0064] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0065] Although the embodiments of the present application have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present application. The scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A preparation method of a composite fiber antibacterial bandage, characterized in that, It includes the following steps: S1. Preparation of antibacterial fiber: Dissolve sodium alginate in water, add quaternary ammonium salt chitosan, mix evenly to obtain an antibacterial impregnating solution, add cotton fiber to it for impregnation, and take it out and dry after impregnation to obtain antibacterial fiber; S2. Preparation of antibacterial fiber: Add polydopamine nanospheres to Tris buffer solution, mix evenly, add diaminopolyethylene glycol and stir to react to obtain an antibacterial impregnating solution, add polyester fiber to it for impregnation, and take it out and dry after impregnation to obtain antibacterial fiber; S3. Mix and spin the antibacterial fiber and the antibacterial fiber, and then weave to obtain a base material for an antibacterial bandage. Immerse it in water, add concentrated ammonia water, mix evenly, let it stand, then add calcium chloride solution for cross-linking. After the reaction is completed, wash and dry to obtain the composite fiber antibacterial bandage.

2. The preparation method of the composite fiber antibacterial bandage according to claim 1, characterized in that, In step S1, the preparation process of quaternary ammonium salt chitosan is as follows: Use isopropanol as a solvent, add chitosan, heat and mix evenly, then adjust the pH of the solution to 8-9, then add an aqueous solution of 2,3-epoxypropyltrimethylammonium chloride, raise the temperature to 75-85 °C and react for 25-30 h. After the reaction is completed, dialyze, filter and dry to obtain quaternary ammonium salt chitosan.

3. The preparation method of the composite fiber antibacterial bandage according to claim 2, characterized in that, The dosage of 2,3-epoxypropyltrimethylammonium chloride in the aqueous solution of 2,3-epoxypropyltrimethylammonium chloride is 0.06-0.1 g / mL.

4. The preparation method of the composite fiber antibacterial bandage according to claim 2, wherein, The mass ratio of isopropanol, chitosan and 2,3-epoxypropyltrimethylammonium chloride is 28-32:1:4-8.

5. The preparation method of the composite fiber antibacterial bandage according to claim 1, characterized in that, In step S2, the preparation process of polydopamine nanospheres is as follows: Add anhydrous ethanol, ammonia water and water to a reactor, mix evenly, add dopamine hydrochloride, react at room temperature for 28-36 h, then centrifuge and separate, and wash to obtain polydopamine nanospheres.

6. The preparation method of the composite fiber antibacterial bandage according to claim 5, characterized in that, The volume ratio of anhydrous ethanol, ammonia water and water is 3.5-5.5:0.1:8.2-12.

5.

7. The preparation method of the composite fiber antibacterial bandage according to claim 5, wherein, The dosage of dopamine hydrochloride in water is 2.2-3.0 mg / mL.

8. A composite fiber antibacterial bandage, characterized in that, Prepared by the preparation method according to any one of claims 1-7.

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