A medical antibacterial dressing and its preparation method

Abstract

The present invention discloses a medical antibacterial dressing and a preparation method thereof, which relates to the technical field of medical materials. The dressing is made by blending chitosan composite fibers, rose fibers, bamboo fibers and antibacterial nanofibers; the weight ratio of the chitosan composite fibers, rose fibers, bamboo fibers and antibacterial nanofibers is 1:(0.2-0.4):0.3:0.5. The medical antibacterial dressing disclosed by the present invention has good antibacterial property and remarkable effect in promoting wound healing.

Description

Technical Field

[0001] The present invention relates to the technical field of medical materials, and particularly relates to a medical antibacterial dressing and a preparation method thereof. Background Art

[0002] A medical dressing is a medical material that directly covers the damaged surfaces such as sores and wounds of an organism, and plays a basic protective role on the surface of the organism. It can provide an ideal environment for wound healing, inhibit bacteria, promote wound healing, and relieve wound pain. With the progress of medical science, the demand for medical dressings is becoming more and more extensive, and the performance requirements for them are also getting higher and higher.

[0003] Currently, the most commonly used medical dressings in clinics are mainly made of gauze, cotton pads, etc., which are mostly processed from cotton, soft linen, and linen cloth, and belong to inert dressings, having no obvious promoting effect on wound healing. Such dressings are cheap, widely available,

[0004] easy to manufacture, have a certain absorbency for wound exudate, can protect the wound surface, and can be reused. However, with the continuous in-depth research on wound repair, due to the disadvantages of being not conducive to wound healing, easy to cause wound infection, poor hemostasis effect, etc., the limitations of such medical dressings are gradually emerging. Other types of medical dressings on the market also still have more or less technical defects such as insufficient antibacterial properties and insignificant promotion effect on wound healing.

[0005] In order to solve the above problems, a Chinese invention patent with the authorization announcement number of CN113318260B discloses a medical antibacterial dressing and a preparation method thereof. The method includes the following steps: after laying a laminated structure in the order of a covering adhesive layer, a hot-melt web adhesive, a porous adsorption material, a hot-melt web adhesive, and a covering adhesive layer, a composite structure of covering adhesive layer / web adhesive / porous adsorption layer / web adhesive / covering adhesive layer is directly obtained by hot pressing; then the composite structure is cut into a plurality of strips of a certain size, and the covering adhesive layer is removed to obtain a composite structure of web adhesive / porous adsorption layer / web adhesive; finally, a medical tape is bonded to one side of the web adhesive / porous adsorption layer / web adhesive composite structure, and a covering adhesive layer with a size matching that of the medical tape is adhered to the other side of the composite structure, and after overall packaging, it is irradiated and sterilized to prepare a medical antibacterial dressing. Compared with the prior art, the medical antibacterial dressing of this invention has a high antibacterial rate, a far-infrared function, a high retention rate of effective adsorption capacity, good air permeability, good moisture permeability, good flexibility, an excellent odor removal function, and strong absorption and infiltration ability. However, its antibacterial property and promotion effect on wound healing still need to be further improved. Summary of the Invention

[0006] In order to overcome the defects in the prior art, the present invention provides a medical antibacterial dressing with good antibacterial property and remarkable promotion effect on wound healing and a preparation method thereof.

[0007] The technical solution adopted by the present invention to solve the technical problem is: a medical antibacterial dressing, which is blended by chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber; the weight ratio of the chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber is 1: (0.2-0.4): 0.3: 0.5; the preparation method of the antibacterial nanofiber comprises the following steps:

[0008] Step D1, adding acrylamide β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trihydroxymethyl methacrylamide, and an initiator to a high boiling point solvent, stirring and reacting at 55-75° C. in an inert gas atmosphere for 4-6 hours, then precipitating in water, washing the precipitated polymer with ethanol 3-6 times, and finally drying in a vacuum drying oven at 85-95° C. to constant weight to obtain an antibacterial copolymer;

[0009] Step D2, adding the antibacterial copolymer prepared in step D1 to 2,2,2-trifluoroethanol, and mixing them uniformly to form a dispersion A; adding hyperbranched polylysine to deionized water, and mixing them uniformly to form a dispersion B; mixing the dispersion A and the dispersion B to obtain a spinning solution;

[0010] Step D3, electrospinning the spinning solution to obtain raw fibers;

[0011] Step D4: dispersing sodium alginate in water to form a modifier, spraying the modifier on the surface of the original fiber, and then post-processing to obtain antibacterial nanofibers.

[0012] Preferably, the mass ratio of acrylamide β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trihydroxymethyl methacrylamide, initiator and high boiling point solvent in step D1 is 1:(0.8-1.2):(3-5):(0.05-0.08):(20-35).

[0013] Preferably, there is no special requirement for the source of the acrylamide β-cyclodextrin quaternary ammonium salt. In one embodiment of the present invention, the acrylamide β-cyclodextrin quaternary ammonium salt is prepared according to the preparation method of reactive β-cyclodextrin quaternary ammonium salt in Example 6 of Chinese invention patent with authorization announcement number CN106008755B.

[0014] Preferably, the initiator is azobisisobutyronitrile; the high boiling point solvent is at least one of dimethyl sulfoxide, N,N-dimethylformamide, and N-methylpyrrolidone; and the inert gas is any one of nitrogen, helium, neon, and argon.

[0015] Preferably, the mass ratio of the antibacterial copolymer and 2,2,2-trifluoroethanol in step D2 is (1.2-2.2):10.

[0016] Preferably, the mass ratio of the hyperbranched polylysine to deionized water in step D2 is (1 - 3):10.

[0017] Preferably, there are no special requirements for the source of the hyperbranched lysine. In one embodiment of the present invention, the hyperbranched lysine is prepared by the method of Example 1 of the Chinese invention patent with the application publication number CN117205361A.

[0018] Preferably, the mass ratio of dispersion system A to dispersion system B in step D2 is 10:(0.4 - 1.6).

[0019] Preferably, the process parameters of the electrospinning in step D3 include: the voltage is 15 - 35 kV, and the distance between the spinneret and the receiver is 12 - 30 cm.

[0020] Preferably, the mass ratio of sodium alginate to water in step D4 is 1:(4 - 6); the mass ratio of sodium alginate to the nanofibers is (1 - 2):10.

[0021] Preferably, the post - treatment in step D4 is specifically: under the conditions of a vacuum gauge pressure of - 0.05 to - 0.15 MPa and a temperature of 80 - 90 °C, vacuum drying for 5 - 10 h.

[0022] Preferably, there are no special requirements for the source of the chitosan composite fiber. In one embodiment of the present invention, the chitosan composite fiber is prepared by the method of Example 9 of the Chinese invention patent with the authorization announcement number CN108914248B.

[0023] Preferably, the rose fiber is Rose fiber viscose cotton 32S, provided by Shaoxing Xineng Textile Technology Co., Ltd.; the fiber fineness of the bamboo fiber is 6D.

[0024] Another object of the present invention is to provide a preparation method of the medical antibacterial dressing, including the following steps: mixing and weaving the chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofibers into a dressing blank, then rolling it through a rolling mill, and then cutting it into 5×5 cm squares, and packaging to obtain the medical antibacterial dressing.

[0025] Preferably, the temperature during the rolling mill rolling is 115 °C - 155 °C, and the speed of the blank passing through the hot roller of the rolling mill is 130 - 320 revolutions per minute.

[0026] The beneficial effects of adopting the above - mentioned technical solutions are as follows:

[0027] (1) The preparation method of the medical antibacterial dressing provided by the present invention has a short process flow, is easy to operate, has high preparation efficiency and high finished product qualification rate, is easy to promote and use, and the product can be industrially produced.

[0028] (2) The medical antibacterial dressing provided by the present invention is made of blended chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber, combining the advantages of these fiber materials, so that the prepared medical antibacterial dressing has good antibacterial property and remarkable effect on promoting wound healing; the antibacterial nanofiber is prepared by electrospinning using acrylamide-based β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trimethylolmethylacrylamide and hyperbranched polylysine as raw materials. By introducing cyclodextrin quaternary ammonium salt, thiazole, hydroxyl group and hyperbranched polylysine structure into the fiber material structure at the same time, under the multiple effects of electronic effect, steric effect and conjugation effect, etc., the prepared medical antibacterial dressing has better antibacterial and wound healing promotion effects, and more sufficient performance stability, and can provide a comfortable healing environment condition for the wound.

[0029] (3) The medical antibacterial dressing provided by the present invention, through the reasonable selection of antibacterial nanofiber and dressing preparation process parameters, makes the prepared medical antibacterial dressing have good skin compatibility, low irritation to the skin, obvious antibacterial effect, remarkable effect on promoting wound healing, long shelf life and sufficient stability. Detailed implementation manners

[0030] In order to enable those skilled in the art to better understand the technical solution of the present invention and make the above features, purposes and advantages of the present invention clearer and more understandable, the present invention will be further described below in conjunction with embodiments. The embodiments are only used to illustrate the present invention and not to limit the scope of the present invention.

[0031] Embodiment 1

[0032] A medical antibacterial dressing, which is made of blended chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber; the weight ratio of the chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber is 1:0.2:0.3:0.5; the preparation method of the antibacterial nanofiber includes the following steps:

[0033] Step D1: Add acrylamide-based β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trimethylolmethylacrylamide, and initiator into a high-boiling solvent. Stir and react at 55 °C for 4 h under an inert gas atmosphere. Then precipitate in water and wash the precipitated polymer with ethanol three times. Finally, place it in a vacuum drying oven and dry at 85 °C to constant weight to obtain an antibacterial copolymer. In step D1, the mass ratio of acrylamide-based β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trimethylolmethylacrylamide, initiator, and high-boiling solvent is 1:0.8:3:0.05:20. The acrylamide-based β-cyclodextrin quaternary ammonium salt is prepared according to the preparation method of reactive β-cyclodextrin quaternary ammonium salt in Example 6 of the Chinese invention patent with the authorization announcement number CN106008755B. The initiator is azobisisobutyronitrile. The high-boiling solvent is dimethyl sulfoxide. The inert gas is nitrogen. Through GPC test, the M n of the obtained functional polymer is measured to be 16381 g / mol, and M W / M n is 1.358. Through elemental analysis, the mass ratio of the structural units introduced by acrylamide-based β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, and N-trimethylolmethylacrylamide is 0.98:0.79:2.99;

[0034] Step D2: Add the antibacterial copolymer prepared in step D1 into 2,2,2-trifluoroethanol and mix evenly to form dispersion system A. Add hyperbranched polylysine into deionized water and mix evenly to form dispersion system B. Mix dispersion system A and dispersion system B to obtain a spinning solution;

[0035] Step D3: Electrospun the spinning solution to obtain nanofibers;

[0036] Step D4: Disperse sodium alginate in water to form a modifier. Spray the modifier on the surface of the nanofibers and then perform post-treatment to obtain antibacterial nanofibers.

[0037] In step D2, the mass ratio of the antibacterial copolymer to 2,2,2-trifluoroethanol is 1.2:10. In step D2, the mass ratio of hyperbranched polylysine to deionized water is 1:10. The hyperbranched lysine is prepared according to the method in Example 1 of the Chinese invention patent with the application publication number CN117205361A. In step D2, the mass ratio of dispersion system A to dispersion system B is 10:0.4.

[0038] The process parameters of the electrospinning in step D3 include: voltage of 15 kV and distance between the spinneret and the receiver of 12 cm. In step D4, the mass ratio of sodium alginate to water is 1:4. The mass ratio of sodium alginate to nanofibers is 1:10.

[0039] The post-treatment described in step D4 is specifically as follows: under the conditions of a vacuum gauge pressure of -0.05 MPa and a temperature of 80 °C, vacuum drying is carried out for 5 h.

[0040] The chitosan composite fiber is prepared by the method of Example 9 of the Chinese invention patent with the authorization announcement number CN108914248B; the rose fiber is Rose fiber viscose cotton 32S, provided by Shaoxing Xineng Textile Technology Co., Ltd.; the fiber fineness of the bamboo fiber is 6D.

[0041] A preparation method of the medical antibacterial dressing includes the following steps: mixing and weaving chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber into a dressing blank, then rolling it through a rolling mill, and then cutting it into 5×5 cm squares, and obtaining the medical antibacterial dressing after packaging; the temperature during the rolling mill rolling is 115 °C, and the speed of the blank passing through the hot roller of the rolling mill is 130 revolutions per minute.

[0042] Example 2

[0043] A medical antibacterial dressing, which is composed of a blend of chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber; the weight ratio of the chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber is 1:0.25:0.3:0.5; the preparation method of the antibacterial nanofiber includes the following steps:

[0044] Step D1: Add acrylamido-β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trimethylolmethylacrylamide and an initiator to a high-boiling solvent, stir and react at 60 °C under an inert gas atmosphere for 4.5 h, then precipitate in water, wash the precipitated polymer 4 times with ethanol, and finally dry it in a vacuum drying oven at 87 °C to constant weight to obtain an antibacterial copolymer.

[0045] Step D2: Add the antibacterial copolymer prepared in step D1 to 2,2,2-trifluoroethanol, and form dispersion system A after mixing evenly; add hyperbranched polylysine to deionized water, and form dispersion system B after mixing evenly; mix dispersion system A and dispersion system B to obtain a spinning solution.

[0046] Step D3: Electrospinning the spinning solution to obtain original fibers.

[0047] Step D4: Disperse sodium alginate in water to form a modifier, spray the modifier on the surface of the original fiber, and then carry out post-treatment to obtain antibacterial nanofibers.

[0048] In step D1, the mass ratio of acrylamido-β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trimethylolmethylacrylamide, initiator, and high-boiling solvent is 1:0.9:3.5:0.06:25; the acrylamido-β-cyclodextrin quaternary ammonium salt is prepared according to the preparation method of reactive β-cyclodextrin quaternary ammonium salt in Example 6 of the Chinese invention patent with the authorization announcement number CN106008755B; the initiator is azobisisobutyronitrile; the high-boiling solvent is N,N-dimethylformamide; the inert gas is helium.

[0049] In step D2, the mass ratio of the antibacterial copolymer and 2,2,2-trifluoroethanol is 1.5:10; in step D2, the mass ratio of the hyperbranched polylysine and deionized water is 1.5:10; the hyperbranched lysine is prepared according to the method in Example 1 of the Chinese invention patent with the application publication number CN117205361A; in step D2, the mass ratio of dispersion system A and dispersion system B is 10:0.8.

[0050] The process parameters of the electrospinning in step D3 include: the voltage is 20 kV, and the distance between the spinneret and the receiver is 16 cm; in step D4, the mass ratio of sodium alginate and water is 1:4.5; the mass ratio of sodium alginate and the nanofibers is 1.2:10; the post-treatment in step D4 is specifically: under the conditions of a vacuum gauge pressure of -0.07 MPa and a temperature of 83 °C, vacuum drying for 6 h.

[0051] The chitosan composite fiber is prepared according to the method in Example 9 of the Chinese invention patent with the authorization announcement number CN108914248B; the rose fiber is Rose fiber viscose cotton 32S, provided by Shaoxing Xineng Textile Technology Co., Ltd.; the fiber fineness of the bamboo fiber is 6 D.

[0052] A preparation method of the medical antibacterial dressing includes the following steps: mixing and weaving the chitosan composite fiber, rose fiber, bamboo fiber, and antibacterial nanofibers into a dressing blank, then rolling it through a rolling mill, and then cutting it into 5×5 cm squares, and packaging to obtain the medical antibacterial dressing; the temperature during the rolling mill rolling is 125 °C, and the speed of the blank passing through the hot roller of the rolling mill is 170 revolutions per minute.

[0053] Example 3

[0054] A medical antibacterial dressing, which is composed of a chitosan composite fiber, rose fiber, bamboo fiber, and antibacterial nanofibers mixed and woven; the weight ratio of the chitosan composite fiber, rose fiber, bamboo fiber, and antibacterial nanofibers is 1:0.3:0.3:0.5; the preparation method of the antibacterial nanofibers includes the following steps:

[0055] Step D1: Add acrylamido-β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trimethylolmethylacrylamide, and initiator into a high-boiling solvent. Under an inert gas atmosphere, stir and react at 65 °C for 5 h. Then precipitate in water and wash the precipitated polymer with ethanol 5 times. Finally, place it in a vacuum drying oven and dry at 90 °C to constant weight to obtain an antibacterial copolymer;

[0056] Step D2: Add the antibacterial copolymer prepared in Step D1 into 2,2,2-trifluoroethanol, and form dispersion system A after mixing evenly; add hyperbranched polylysine into deionized water, and form dispersion system B after mixing evenly; mix dispersion system A and dispersion system B to obtain a spinning solution;

[0057] Step D3: Electrospun the spinning solution to obtain nanofibers;

[0058] Step D4: Dissolve sodium alginate in water to form a modifier, spray the modifier on the surface of the nanofibers, and then perform post-treatment to obtain antibacterial nanofibers.

[0059] The mass ratio of acrylamido-β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trimethylolmethylacrylamide, initiator, and high-boiling solvent in Step D1 is 1:1:4:0.065:28; the acrylamido-β-cyclodextrin quaternary ammonium salt is prepared according to the preparation method of reactive β-cyclodextrin quaternary ammonium salt in Example 6 of the Chinese invention patent with the authorization announcement number CN106008755B; the initiator is azobisisobutyronitrile; the high-boiling solvent is N-methylpyrrolidone; the inert gas is neon.

[0060] The mass ratio of the antibacterial copolymer and 2,2,2-trifluoroethanol in Step D2 is 1.8:10; the mass ratio of hyperbranched polylysine and deionized water in Step D2 is 2:10; the hyperbranched lysine is prepared according to the method in Example 1 of the Chinese invention patent with the application publication number CN117205361A; the mass ratio of dispersion system A and dispersion system B in Step D2 is 10:1.

[0061] The process parameters of the electrospinning in Step D3 include: voltage of 28 kV, distance between the spinneret and the receiver of 23 cm; the mass ratio of sodium alginate and water in Step D4 is 1:5; the mass ratio of sodium alginate and nanofibers in Step D4 is 1.5:10; the post-treatment in Step D4 is specifically: under a vacuum gauge pressure of -0.1 MPa and a temperature of 85 °C, vacuum dry for 7.5 h.

[0062] The chitosan composite fiber is prepared according to the method in Example 9 of the Chinese invention patent with the authorization announcement number CN108914248B; the rose fiber is Rose fiber viscose cotton 32S, provided by Shaoxing Xineng Textile Technology Co., Ltd.; the fiber fineness of the bamboo fiber is 6D.

[0063] A preparation method of the medical antibacterial dressing includes the following steps: mixing and weaving chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber into a dressing blank, then rolling and pressing by a rolling mill, and then cutting into 5×5 cm squares, and obtaining the medical antibacterial dressing after packaging; the temperature during the rolling and pressing by the rolling mill is 135 °C, and the speed of the blank passing through the hot roller of the rolling mill is 230 revolutions per minute.

[0064] Example 4

[0065] A medical antibacterial dressing is made by mixing and weaving chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber; the weight ratio of the chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber is 1:0.35:0.3:0.5; the preparation method of the antibacterial nanofiber includes the following steps:

[0066] Step D1: Add acrylamido-β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trimethylolmethylacrylamide and initiator into a high-boiling solvent, stir and react at 70 °C for 5.5 h in an inert gas atmosphere, then precipitate in water, wash the precipitated polymer with ethanol 6 times, and finally dry it to constant weight at 93 °C in a vacuum drying oven to obtain an antibacterial copolymer;

[0067] Step D2: Add the antibacterial copolymer prepared in Step D1 into 2,2,2-trifluoroethanol, and form dispersion system A after mixing evenly; add hyperbranched polylysine into deionized water, and form dispersion system B after mixing evenly; mix dispersion system A and dispersion system B to obtain a spinning solution;

[0068] Step D3: Electrospin the spinning solution to obtain raw fibers;

[0069] Step D4: Disperse sodium alginate in water to form a modifier, spray the modifier on the surface of the raw fibers, and then perform post-treatment to obtain antibacterial nanofibers.

[0070] In Step D1, the mass ratio of acrylamido-β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trimethylolmethylacrylamide, initiator and high-boiling solvent is 1:1.1:4.5:0.075:33; the acrylamido-β-cyclodextrin quaternary ammonium salt is prepared according to the preparation method of the reactive β-cyclodextrin quaternary ammonium salt in Example 6 of the Chinese invention patent with the authorization announcement number CN106008755B; the initiator is azobisisobutyronitrile; the high-boiling solvent is a mixture of dimethyl sulfoxide, N,N-dimethylformamide and N-methylpyrrolidone in a mass ratio of 1:1:2; the inert gas is argon.

[0071] In step D2, the mass ratio of the antibacterial copolymer to 2,2,2-trifluoroethanol is 2:10; in step D2, the mass ratio of the hyperbranched polylysine to deionized water is 2.5:10; the hyperbranched lysine is prepared according to the method of Example 1 of the Chinese invention patent with the application publication number CN117205361A; in step D2, the mass ratio of dispersion system A to dispersion system B is 10:1.4; in step D3, the process parameters of the electrospinning include: the voltage is 33 kV and the distance between the spinneret and the receiver is 28 cm; in step D4, the mass ratio of sodium alginate to water is 1:5.5; the mass ratio of sodium alginate to the nanofibers is 1.8:10; the post-treatment in step D4 is specifically: under the conditions of a vacuum gauge pressure of -0.13 MPa and a temperature of 88 °C, vacuum drying for 9 h.

[0072] The chitosan composite fiber is prepared according to the method of Example 9 of the Chinese invention patent with the authorization announcement number CN108914248B; the rose fiber is Rose fiber viscose cotton 32S, provided by Shaoxing Xinen Textile Technology Co., Ltd.; the fiber fineness of the bamboo fiber is 6 D.

[0073] A preparation method of the medical antibacterial dressing includes the following steps: mixing and weaving the chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofibers into a dressing blank, then rolling and pressing through a rolling mill, and then cutting into 5×5 cm squares, and packaging to obtain the medical antibacterial dressing; the temperature during the rolling and pressing by the rolling mill is 145 °C, and the speed of the blank passing through the hot roller of the rolling mill is 300 revolutions per minute.

[0074] Example 5

[0075] A medical antibacterial dressing, which is made by mixing and weaving chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofibers; the weight ratio of the chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofibers is 1:0.4:0.3:0.5; the preparation method of the antibacterial nanofibers includes the following steps:

[0076] Step D1: Add acrylamido-β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trimethylolmethylacrylamide and an initiator to a high-boiling solvent, stir and react at 75 °C for 6 h under an inert gas atmosphere, then precipitate in water, wash the precipitated polymer with ethanol 6 times, and finally place it in a vacuum drying oven at 95 °C to dry to a constant weight to obtain an antibacterial copolymer;

[0077] Step D2: Add the antibacterial copolymer prepared in Step D1 into 2,2,2-trifluoroethanol. After mixing evenly, a dispersion system A is formed; add hyperbranched polylysine into deionized water. After mixing evenly, a dispersion system B is formed; mix dispersion system A and dispersion system B to obtain a spinning solution;

[0078] Step D3: Electrospun the spinning solution to obtain precursor fibers;

[0079] Step D4: Disperse sodium alginate in water to form a modifier. Spray the modifier on the surface of the precursor fibers, and then through post-treatment to obtain antibacterial nanofibers.

[0080] In Step D1, the mass ratio of acrylamido-β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trimethylolmethylacrylamide, initiator, and high-boiling solvent is 1:1.2:5:0.08:35; the acrylamido-β-cyclodextrin quaternary ammonium salt is prepared according to the preparation method of reactive β-cyclodextrin quaternary ammonium salt in Example 6 of the Chinese invention patent with the authorization announcement number CN106008755B; the initiator is azobisisobutyronitrile; the high-boiling solvent is dimethyl sulfoxide; the inert gas is nitrogen.

[0081] In Step D2, the mass ratio of the antibacterial copolymer to 2,2,2-trifluoroethanol is 2.2:10; in Step D2, the mass ratio of hyperbranched polylysine to deionized water is 3:10; the hyperbranched lysine is prepared according to the method in Example 1 of the Chinese invention patent application publication number CN117205361A; in Step D2, the mass ratio of dispersion system A to dispersion system B is 10:1.6; the process parameters of the electrospinning in Step D3 include: the voltage is 35 kV, and the distance between the spinneret and the receiver is 30 cm; in Step D4, the mass ratio of sodium alginate to water is 1:6; the mass ratio of sodium alginate to the precursor fibers is 2:10; the specific post-treatment in Step D4 is: under the conditions of a vacuum gauge pressure of -0.15 MPa and a temperature of 90 °C, vacuum dry for 10 h.

[0082] The chitosan composite fiber is prepared according to the method in Example 9 of the Chinese invention patent with the authorization announcement number CN108914248B; the rose fiber is Rose fiber viscose cotton 32S, provided by Shaoxing Xineng Textile Technology Co., Ltd.; the fiber fineness of the bamboo fiber is 6 D.

[0083] A preparation method of the medical antibacterial dressing includes the following steps: Mix and weave the chitosan composite fiber, rose fiber, bamboo fiber, and antibacterial nanofibers into a dressing blank fabric, then roll and press it through a rolling mill, and then cut it into 5×5 cm squares, and package it to obtain the medical antibacterial dressing; the temperature during the rolling mill rolling and pressing is 155 °C, and the speed of the blank fabric passing through the hot roller of the rolling mill is 320 revolutions per minute.

[0084] Comparative Example 1

[0085] A medical antibacterial dressing, which is basically the same as Example 1, except that 4-methyl-5-vinylthiazole is not added, and bamboo fiber is used to replace rose fiber in equal amount.

[0086] Comparative Example 2

[0087] A medical antibacterial dressing, which is basically the same as Example 1, except that acrylamido-β-cyclodextrin quaternary ammonium salt is not added, and rose fiber is used to replace bamboo fiber in equal amount.

[0088] The medical antibacterial dressings described in Examples 1-5 and Comparative Examples 1-2 were subjected to performance tests. The test results are shown in Table 1, and the test methods are as follows:

[0089] (1) Antibacterial property: The antibacterial rate was tested with reference to GB / T 20944.3-2008.

[0090] (2) Animal wound healing experiment: 84 rabbits (in good health, weighing 2-3 kg) were divided into 7 groups (Group A, Group B, Group C, Group D, Group E, Group F, Group G), with 12 rabbits in each group. A 5 cm×5 cm hair-removed area was reserved on the back of the rabbits. After disinfection, a 1 cm×1 cm wound was made on their backs with a scalpel. The wounds were treated with the dressings prepared in Examples 1-5 and Comparative Examples 1-2 of the present invention, and the dressings were changed twice a day; after 7 days, the healing conditions of the rabbit wounds were statistically recorded. Among them, the wound healing rate (%) = (original wound area - unhealed wound area) / original wound area × 100%, and the average value of the wound healing rates of the rabbits in each group was taken as the animal wound healing rate of this product.

[0091] Table 1

[0092]

[0093] It can be seen from Table 1 that the medical antibacterial dressings disclosed in the examples of the present invention have more excellent antibacterial properties and wound healing promotion effects compared with the comparative examples; the combined use of 4-methyl-5-vinylthiazole, acrylamido-β-cyclodextrin quaternary ammonium salt, bamboo fiber, and rose fiber is beneficial to improving the above properties.

[0094] The foregoing has shown and described the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments, and what is described in the above embodiments and the specification is only the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection required by the present invention is defined by the appended claims and their equivalents.

Claims

1. A medical antibacterial dressing, characterized in that: The dressing is blended by chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber; the weight ratio of the chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber is 1:(0.2-0.4):0.3:0.5; the preparation method of the antibacterial nanofiber comprises the following steps: Step D1, adding acrylamide β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trihydroxymethyl methacrylamide, and an initiator to a high boiling point solvent, stirring and reacting at 55-75° C. in an inert gas atmosphere for 4-6 hours, then precipitating in water, washing the precipitated polymer with ethanol 3-6 times, and finally drying in a vacuum drying oven at 85-95° C. to constant weight to obtain an antibacterial copolymer; Step D2, adding the antibacterial copolymer prepared in step D1 to 2,2,2-trifluoroethanol, and mixing them evenly to form a dispersion A; adding hyperbranched polylysine to deionized water, and mixing them evenly to form a dispersion B; and mixing the dispersion A and the dispersion B to obtain a spinning solution; Step D3, electrospinning the spinning solution to obtain raw fibers; Step D4: dispersing sodium alginate in water to form a modifier, spraying the modifier on the surface of the original fiber, and then post-processing to obtain antibacterial nanofibers.

2. The medical antibacterial dressing according to claim 1, characterized in that: The mass ratio of acrylamide β-cyclodextrin quaternary ammonium salt, 4-methyl-5-vinylthiazole, N-trihydroxymethyl methacrylamide, initiator and high boiling point solvent in step D1 is 1:(0.8-1.2):(3-5):(0.05-0.08):(20-35).

3. The medical antibacterial dressing according to claim 1, characterized in that: The initiator is azobisisobutyronitrile; the high boiling point solvent is at least one of dimethyl sulfoxide, N,N-dimethylformamide, and N-methylpyrrolidone; and the inert gas is any one of nitrogen, helium, neon, and argon.

4. The medical antibacterial dressing according to claim 1, characterized in that: The mass ratio of the antibacterial copolymer and 2,2,2-trifluoroethanol in step D2 is (1.2-2.2):

10.

5. The medical antibacterial dressing according to claim 1, characterized in that: The mass ratio of the hyperbranched polylysine to deionized water in step D2 is (1-3):

10.

6. The medical antibacterial dressing according to claim 1, characterized in that: The mass ratio of dispersion A to dispersion B in step D2 is 10:(0.4-1.6).

7. The medical antibacterial dressing according to claim 1, characterized in that: The process parameters of the electrospinning described in step D3 include: a voltage of 15-35 kV, a distance between the spinneret and the receiver of 12-30 cm; the mass ratio of sodium alginate to water described in step D4 is 1:(4-6); the mass ratio of sodium alginate to fibril is (1-2):10; the post-treatment described in step D4 is specifically: vacuum drying for 5-10 hours under vacuum gauge pressure of -0.05 to -0.15 MPa and temperature of 80-90°C.

8. The medical antibacterial dressing according to claim 1, characterized in that: The fiber fineness of the bamboo fiber is 6D.

9. A method for preparing the medical antibacterial dressing according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: chitosan composite fiber, rose fiber, bamboo fiber and antibacterial nanofiber are blended to form dressing cloth, which is then rolled by a rolling mill and cut into 5×5 cm squares, and the medical antibacterial dressing is obtained after packaging.

10. The method for preparing the medical antibacterial dressing according to claim 9, characterized in that: The temperature of the rolling mill during rolling is 115° C.-155° C., and the speed at which the grey cloth passes through the hot roller of the rolling mill is 130-320 rpm.

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