CN104189942A - Antibacterial wound dressing and preparation method thereof - Google Patents

Abstract

The invention provides an antibacterial composite wound dressing and a preparation method thereof. The antibacterial composite wound dressing is characterized in that it comprises a chitosan-based drug-loaded composite antibacterial superfine fiber membrane, calcium alginate fiber nonwoven fabric and a supporting protective layer arranged sequentially from top to bottom. The drug-loaded ultra-fine fiber membrane prepared by the electrospinning method in the present invention can effectively increase the surface area of the drug, and utilize the high porosity and uniform pore diameter of the ultra-fine fiber to release the drug slowly and continuously, so that the drug can be fully Absorbed by the human body, the effect of the drug can be maintained without frequent administration, and the toxic and side effects of the drug are reduced.

Description

A kind of antibacterial wound dressing and preparation method thereof

technical field

The invention belongs to the technical field of preparation of composite antibacterial wound dressings, and in particular relates to a novel medical dressing with antibacterial, hemostatic and healing functions and a preparation method thereof.

Background technique

At present, traditional dressings are mainly used for nursing care of skin injuries caused by trauma, scalds, burns, bedsores, diabetic ulcers, varicose ulcers, and surgical incisions. However, there are defects such as no antibacterial properties, poor air permeability, and easy adhesion, which can easily lead to repeated damage and damage to the skin, slow down the healing speed, and cause adverse consequences such as secondary bacterial infections. Among them, bacterial infection is one of the main factors affecting wound healing. Wound exudate contains a large number of inflammatory factors, proteases and free radicals, which will affect the speed of wound healing. The development of new composite antibacterial dressings is of great significance to the treatment of skin injuries, and is an inevitable trend in the development of new wound dressings.

Chitosan (Chitosan) is a natural polymer material and a polycation electrolyte naturally occurring in nature. It has antibacterial, hemostatic and healing effects, low toxicity, biodegradable, and non-irritating to skin and mucous membranes. And it is mucoadhesive. Because chitosan has good biological characteristics, it has a positive effect on promoting wound repair, and it is widely recognized as a good wound repair material. There are many active groups on the chitosan macromolecule, which can realize drug loading and controlled release. It is a good drug carrier material. Although there are many studies on chitosan as a drug carrier, its main form It is cast film, sponge and microsphere, or non-woven fabric or fabric composed of single fiber with a diameter of about 10 μm. The ultrafine fiber membrane prepared by electrospinning has the characteristics of fine fiber diameter, large specific surface area, and high porosity. This structural feature shows unique properties when used as a carrier material.

Alginate is processed from alginic acid extracted from brown seaweed, and the cost is low, and the materials used in the processing process are not toxic. The alginate fiber developed with alginate as raw material is non-toxic, highly water-absorbing and gelling, high oxygen permeability, good biocompatibility, good biodegradable absorption, hemostatic performance, and effectively promotes wound healing. High ion adsorption and other superior properties have been widely used in biomedical research. In addition, calcium alginate has good liquid absorption performance, and can absorb exudates equivalent to 20 times its own weight, which is 5-7 times that of ordinary gauze. When in contact with wound exudate, soluble sodium alginate is produced through ion exchange, and at the same time calcium ions are released into the wound to induce platelet activation and accelerate wound healing; calcium alginate can also adsorb bacteria, prevent bacteria from entering the wound, and activate Macrophages defend against the invasion of pathogenic microorganisms.

Among the existing patents, Publication No. CN 102600497A discloses a silver ion antibacterial medical dressing, which mixes an antibacterial agent with silver ions and viscose fiber before weaving to prepare a product with strong anti-infection ability. However, the dressing prepared by this method only has antibacterial and antibacterial functions, and does not involve in improving wounds, accelerating wound healing and breathability. Publication number CN 102335451 A discloses the preparation of a dressing composed of water-soluble chitin and methylguanidine, which has healing-promoting and antibacterial effects, but the liquid absorption of this product is poor. Publication number CN 102264323 A discloses a wound dressing. The prepared dressing has a support layer (polymer film) and an absorbent layer. The absorbent pad includes at least two different absorbent layers (viscose fiber and thermoplastic fiber). Three layers (containing silver antibacterial agent) are separated, and at least one antibacterial agent plays its role in the absorbent pad, which solves the phenomenon of antibacterial agent overload. Patent No. US 8293964B2 discloses an antibacterial layer of silver-containing fabric as the first layer, and the other two layers are composed of an absorbent layer (non-porous elastic material) that absorbs tissue exudates and an air-permeable and impermeable support layer. A medical dressing that can prevent wound infection and promote wound healing. The patent No. US 7030288 B2 discloses a method consisting of an absorbent layer (viscose fiber, etc.), a drug-loaded layer (antibacterial agent), an adhesive layer (pressure-sensitive adhesive) and a support layer (polyester, etc.), which can be loaded with antibiotics. The antibacterial effect of similar drugs is achieved, and the absorbent layer can effectively absorb tissue exudate and accelerate wound healing. Publication number CN103611182 A discloses a wound dressing loaded with organic antibacterial drugs prepared by coaxial electrospinning, which has good antibacterial properties, water absorption and air permeability, and utilizes the high porosity and large specific surface area of nanofibers , so that the loaded antibacterial drugs can be released continuously and stably, achieving a lasting antibacterial effect.

At present, in the research on antibacterial dressings loaded with antibacterial agents, most of them are based on the research and application of silver-loaded antibacterial dressings, and there are few reports on drugs loaded with organic antibacterial agents. However, the biological negative effects of nano-silver on the human body, especially The chronic toxicity of long-term frequent use or large-scale use is not very clear. And because the composite dressing loaded with organic antibacterial drugs has the advantages of rapid onset and obvious antibacterial effect, it will not destroy the substrate and drug activity during the preparation process, and will not produce obvious drug resistance during the treatment period. At the same time, it is made of alginate fiber. The absorbent layer can effectively absorb tissue exudate, maintain a moist environment of the wound, and have a certain hemostatic function.

Contents of the invention

The purpose of the present invention is to propose a kind of antimicrobial compound microfiber film that uses chitosan as the carrier to load organic antibacterial drugs as the antibacterial layer, uses alginate non-woven fabric as the absorption layer, and uses materials such as hydrophobic and breathable polyester as the support layer. Antibacterial wound dressing and preparation method thereof. Based on electrospinning film-forming technology, chitosan is used as the drug-loading system, which reduces the diffusion rate of the drug in the carrier and prolongs the release time, allowing the drug to be released step by step at the wound of the human body without frequent administration. Maintain the effective drug concentration at the wound for a long time. The alginate material is used as the absorption system, which can effectively absorb tissue exudate, form a gel state, maintain a moist environment of the wound, and promote wound healing. At the same time, it exerts the hemostatic properties of chitosan and alginate. The support layer not only ensures the softness and air permeability of the dressing, but also can better block the external moisture. This multi-layer composite structure combines the advantages of each layer of materials, and can well meet the needs of patients for wound repair and medical care for medical staff.

In order to achieve the above object, the present invention provides an antibacterial composite wound dressing, which is characterized in that it comprises a chitosan-based drug-loaded composite antibacterial microfiber membrane (1), calcium alginate fiber and Non-woven fabric (2) and supporting protective layer (3).

Preferably, the support protection layer (3) is polyacrylate pressure-sensitive adhesive, polyurethane film, polyethylene film, non-woven fabric of polypropylene fiber, non-woven fabric of ethylene-propylene composite fiber (ES fiber) or polypropylene A nonwoven fabric made of a blend of fibers and ethylene-propylene composite fibers.

The present invention also provides the preparation method of above-mentioned antibacterial composite wound dressing, it is characterized in that, concrete steps comprise:

The first step: add antimicrobial drug powder into the aqueous solution of acetic acid with a mass fraction of 2-95%, stir it with a magnetic stirrer to make it fully dissolve, weigh chitosan and polyethylene oxide powder and add it to the above solution, and stir to obtain spinning Silk solution; under the conditions of spinning voltage of 8-30Kv, spinning solution feed rate of 0.08-1.2mL/h, receiving distance of 10-35cm, ambient temperature of 15-50°C and relative humidity of 20-60% Electrospinning is carried out under the environment, and the obtained nanofiber membrane is placed in a desiccator filled with 20-30% glutaraldehyde aqueous solution, cross-linked for 12-36 hours, and then dried in a vacuum oven for 12-36 hours to remove residual Solvent and cross-linking agent glutaraldehyde to obtain chitosan-based drug-loaded composite antibacterial microfiber membrane (1), the fiber diameter of which is 150-400nm;

Step 2: Calcium alginate fiber is used, followed by opening, carding, web laying and spunlace in sequence to prepare calcium alginate fiber non-woven fabric (2), which is used as the absorption layer of tissue infiltration fluid;

The third step: the chitosan-based drug-loaded composite antibacterial microfiber membrane (1) and the calcium alginate fiber non-woven fabric (2) are bonded together with a bioadhesive, and then bonded with the supporting protective layer (3) Composite, cut into a certain specification of antibacterial composite wound dressing.

Preferably, the concentration of polyethylene oxide in the spinning solution in the first step is 0.3-0.6wt%, the weight ratio of chitosan to polyethylene oxide is 10-93:10, the ratio of antibacterial drugs to polyethylene oxide The weight ratio is 5-15:10.

Preferably, the chitosan in the first step is a white powder with a degree of deacetylation>95%, and its grade is medical grade, and the polyoxyethylene is a white powder with a molecular weight of 400-1000KDa.

Preferably, the antibacterial drug in the first step is moxifloxacin hydrochloride, ciprofloxacin hydrochloride, mefoxin (cefoxitin sodium), levofloxacin hydrochloride, amoxicillin or tetracycline hydrochloride.

Preferably, the carding and laying process parameters in the second step are: carding machine feeding speed 0.2-0.9m/min, cylinder speed 500-900m/min, output fiber web speed 40-70m/min, The web laying speed is 40-60m/min, and the unevenness of the output web is 1.5-4%.

Preferably, the cutting speed in the third step is 100-400m/min.

Preferably, the liquid absorption rate of the obtained antibacterial composite wound dressing is 500-2000%, the liquid retention rate is 600-1000%, and the diameter of the antibacterial zone is 10-35mm.

Preferably, the drug-loading rate of the chitosan-based drug-loaded composite antibacterial microfiber membrane (1) is 90-96%.

Compared with prior art, the beneficial effect of the present invention is:

1. The drug-loaded ultra-fine fiber membrane prepared by the electrospinning method of the present invention can effectively increase the surface area of the drug, and utilize the high porosity and uniform pore size of the ultra-fine fiber to release the drug slowly and continuously, so that the drug can Fully absorbed by the human body, without frequent administration, the effect of the drug can be maintained, and the toxic and side effects of the drug can be reduced.

2. The drug-loaded fiber membrane material of the present invention takes chitosan as a carrier, and chitosan itself has broad-spectrum antibacterial, hemostasis, wound healing, and good biocompatibility and biodegradability, and can be used as a dressing with Antibacterial drugs work together to form a compound antibacterial effect. Dressings with different drug loadings can also be designed for different degrees of wound treatment according to needs, effectively promoting wound healing.

3. The microfiber membrane of the present invention is soft and easy to fit with the skin, and has good flexibility. When using a wound dressing, it can be cut according to the size of the wound to reduce the irritation of the dressing on the wound tissue. At the same time, it can also prevent wound adhesion and avoid secondary trauma.

4. The calcium alginate fiber of the present invention has good liquid absorption performance, can absorb exudate equivalent to 20 times its own weight, which is 5-7 times that of ordinary gauze, and can effectively prevent wound effusion infection. When in contact with wound exudate, soluble sodium alginate is produced through ion exchange, and calcium ions are released into the wound at the same time, which induces platelet activation and accelerates wound healing.

5. The supporting protection layer of the present invention adopts materials with good water resistance and impermeability, which can well prevent the invasion of external bacteria, microorganisms and moisture, and the waterproof level can reach between 4-5.

6. The materials selected in the present invention have simple preparation process, wide sources, cheap and easy to obtain, and are environmentally friendly and biodegradable. They can be combined into antibacterial medical dressings through medical adhesives, which are suitable for mass production and can reduce the generation of medical waste at the same time .

7. The antibacterial wound dressing prepared by the inventive method can be used for the repair of skin wounds such as clinical surgical incisions, wounds, burns, scalds, bedsores or ulcers.

Description of drawings

Fig. 1 is a schematic structural view of the antibacterial composite functional wound dressing of the present invention, wherein 1-antibacterial layer, 2-absorbent layer, 3-support layer.

Fig. 2 is the scanning electron microscope picture of the loaded ciprofloxacin hydrochloride superfine fiber that obtains in embodiment 1;

Fig. 3 is the scanning electron microscope picture of the loaded moxifloxacin hydrochloride superfine fiber that obtains in embodiment 3;

Fig. 4 is the outline drawing of the loaded ciprofloxacin hydrochloride composite antibacterial dressing obtained in embodiment 1.

Fig. 5 is the antibacterial effect figure of the loaded ciprofloxacin hydrochloride microfiber obtained in embodiment 1,2,3;

Fig. 6 is the antibacterial effect figure of the loaded moxifloxacin hydrochloride microfiber obtained in embodiment 4;

Detailed ways

In order to make the present invention more comprehensible, preferred embodiments are described in detail as follows. Chitosan (CS) used in the following examples is a white powder with a degree of deacetylation>95%, and its grade is medical grade. The polyethylene oxide (PEO) is a white powder with a molecular weight of 400-1000KDa.

Example 1

As shown in Figure 1, it is a schematic structural view of the antibacterial composite wound dressing of the present invention, and the antibacterial composite wound dressing includes a chitosan-based drug-loaded composite antibacterial microfiber membrane 1 sequentially arranged from top to bottom , calcium alginate fiber non-woven fabric 2 and support protection layer 3. The supporting protective layer 3 is polyacrylate pressure-sensitive adhesive.

The concrete steps of the preparation method of described antibacterial composite wound dressing are:

Add antimicrobial drug ciprofloxacin hydrochloride powder in the acetic acid aqueous solution that mass fraction is 90%, make it fully dissolve with magnetic stirrer stirring, take chitosan and polyoxyethylene powder and join in the above-mentioned solution, stir to obtain uniform, Stable spinning solution, the concentration of polyethylene oxide in the spinning solution is 0.5wt%, the weight ratio of chitosan and polyethylene oxide is 90:10, and the weight ratio of antibacterial drug and polyethylene oxide is 5: 10. Electrospinning was carried out for 8 hours under the conditions of a spinning voltage of 16kv, a feeding rate of spinning solution of 0.5mL/h, a receiving distance of 20cm, an ambient temperature of 25°C and a relative humidity of 35%, and the prepared The nanofibrous membrane was placed in a desiccator filled with 25% glutaraldehyde aqueous solution, cross-linked for 24 hours, and then dried in a vacuum oven for 24 hours to remove residual solvents and cross-linking agent glutaraldehyde, and finally in the desiccator to avoid light save. As shown in Figure 2, the fiber diameter of the obtained chitosan-based drug-loaded composite antibacterial microfiber membrane is 238±35nm, and the drug-loading rate is 94%.

100% calcium alginate fibers are used to undergo opening, carding, web laying and spunlace in sequence. The process parameters of carding and web laying are: the feeding speed of the carding machine is 0.8m/min, the cylinder speed is 750m/min, and the output fiber web The speed is 45m/min, the laying speed is 50m/min, and the unevenness of the output fiber web is 2.5%. The process parameters of the spunlace are: the pressure of the pre-wet spunlace head is 25Pa, and the pressure of the spunlace head is 35Pa respectively. , 35Pa, 45Pa, 45Pa, the production speed of the spunlace machine is 10m/min, and the calcium alginate fiber nonwoven fabric 2 is prepared, which is used as the tissue permeation liquid absorption layer.

The chitosan-based drug-loaded composite antibacterial microfiber membrane 1 and the calcium alginate fiber nonwoven fabric 2 are bonded together using bioadhesive polyacrylic acid, and then polyacrylic acid is applied on the calcium alginate fiber nonwoven fabric 2 Ester pressure-sensitive adhesive, and finally, after covering the antibacterial layer with centrifugal paper, it is cut at a speed of 200m/min to become an antibacterial composite wound dressing of a certain specification as shown in Figure 4. After testing, the product has good antibacterial, hemostatic and healing effects, as well as good air permeability and moisture absorption. Among them, the determination of the antibacterial zone is that after the composite dressing is placed in the bacterial culture dish for 18-24 hours, it is tested at room temperature with a digital display vernier caliper immediately after it is taken out from the incubator. Staphylococcus aureus (SA) 18mm and Escherichia coli (EC) 24mm, as shown in sample No. 1 in Fig. 5 . The liquid absorption rate of the dressing is 1615.2%, the liquid retention rate is 821.2%, and the waterproof grade is 5.

Example 2

As shown in Figure 1, it is a schematic structural view of the antibacterial composite wound dressing of the present invention, and the antibacterial composite wound dressing includes a chitosan-based drug-loaded composite antibacterial microfiber membrane 1 sequentially arranged from top to bottom , calcium alginate fiber non-woven fabric 2 and support protection layer 3. The supporting protection layer 3 is provided with polyacrylate pressure-sensitive adhesive.

The concrete steps of the preparation method of described antibacterial composite wound dressing are:

Add antimicrobial drug ciprofloxacin hydrochloride powder in the acetic acid aqueous solution that mass fraction is 90%, make it fully dissolve with magnetic stirrer stirring, take chitosan and polyoxyethylene powder and join in the above-mentioned solution, stir to obtain uniform, Stable spinning solution, the concentration of polyethylene oxide in the spinning solution is 0.5wt%, the weight ratio of chitosan and polyethylene oxide is 90:10, and the weight ratio of antibacterial drug and polyethylene oxide is 10: 10. Under the conditions of spinning voltage of 16kv, spinning solution feed rate of 0.8mL/h, receiving distance of 20cm, ambient temperature of 25°C and relative humidity of 35%, electrospinning was carried out for 8h, and the prepared The nanofibrous membrane was placed in a desiccator filled with 25% glutaraldehyde aqueous solution, cross-linked for 24 hours, and then dried in a vacuum oven for 24 hours to remove residual solvents and cross-linking agent glutaraldehyde, and finally in the desiccator to avoid light save. The obtained chitosan-based drug-loaded composite antibacterial ultrafine fiber membrane has a fiber diameter of 200+30nm and a drug-loading rate of 94%.

100% calcium alginate fibers are used to go through opening, carding, web laying and spunlace in sequence. The process parameters of carding and web laying are: the feeding speed of the carding machine is 0.7m/min, the cylinder speed is 700m/min, and the output fiber web The speed is 40m/min, the laying speed is 45 m/min, and the unevenness of the output fiber web is 3%. The process parameters of the spunlace are: the pressure of the pre-wet spunlace head is 30Pa, and the pressure of the spunlace head is respectively 40 Pa, 40 Pa, 45Pa, 45Pa, the production speed of the spunlace machine is 12m/min, and the calcium alginate fiber nonwoven fabric 2 is prepared as the tissue infiltration liquid absorption layer.

The chitosan-based drug-loaded composite antibacterial microfiber membrane 1 and the calcium alginate fiber nonwoven fabric 2 are bonded together using bioadhesive polyacrylic acid, and then polyacrylic acid is applied on the calcium alginate fiber nonwoven fabric 2 Ester pressure-sensitive adhesive, and finally, after covering the antibacterial layer with centrifugal paper, it is cut at a speed of 200m/min to become an antibacterial composite wound dressing of a certain specification. After testing, the product has good antibacterial, hemostatic and healing effects, as well as good air permeability and moisture absorption. Among them, the determination of the antibacterial zone is that after the composite dressing is placed in the bacterial culture dish for 18-24 hours, it is tested at room temperature with a digital display vernier caliper immediately after it is taken out from the incubator. Staphylococcus aureus (SA) 15mm and Escherichia coli (EC) 25mm, as shown in sample No. 2 in Fig. 5 . The liquid absorption rate of the dressing is 2017.9%, the liquid retention rate is 777.7%, and the waterproof grade is 4.5.

Example 3

As shown in Figure 1, it is a schematic structural view of the antibacterial composite wound dressing of the present invention, and the antibacterial composite wound dressing includes a chitosan-based drug-loaded composite antibacterial microfiber membrane 1 sequentially arranged from top to bottom , calcium alginate fiber non-woven fabric 2 and support protection layer 3. The supporting protective layer 3 is a polyethylene film with biological glue.

The concrete steps of the preparation method of described antibacterial composite wound dressing are:

Add antibacterial drug powder moxifloxacin hydrochloride to 90% acetic acid aqueous solution by mass fraction, stir it with a magnetic stirrer to fully dissolve it, weigh chitosan and polyethylene oxide powder and add it to the above solution, and stir to obtain a uniform, stable spinning solution, the concentration of polyoxyethylene in the spinning solution is 0.5wt%, the weight ratio of chitosan and polyoxyethylene is 90:10, and the weight ratio of antibacterial drug and polyoxyethylene is 5:10 , under the conditions of spinning voltage of 16kv, spinning solution feed rate of 0.5mL/h, receiving distance of 20cm, ambient temperature of 25°C and relative humidity of 35%, electrospinning was carried out for 8h, and the prepared nano The fiber membrane was placed in a desiccator filled with 25% glutaraldehyde aqueous solution, cross-linked for 24 hours, and then dried in a vacuum oven for 24 hours to remove residual solvents and cross-linking agent glutaraldehyde, and finally protected from light in the desiccator save. As shown in Figure 3, the fiber diameter of the obtained chitosan-based drug-loaded composite antibacterial ultrafine fiber membrane is 300+61 nm, and the drug-loading rate is 92%.

100% calcium alginate fibers are used to undergo opening, carding, web laying and spunlace in sequence. The process parameters of carding and web laying are: the feeding speed of the carding machine is 0.9m/min, the cylinder speed is 850m/min, and the output fiber web The speed is 55m/min, the laying speed is 50m/min, and the unevenness of the output fiber web is 3%; the process parameters of the spunlace are: the pressure of the pre-wet spunlace head is 25Pa, and the pressure of the spunlace head is 35Pa , 35Pa, 45Pa, 45Pa, the production speed of the spunlace machine is 15m/min, and the calcium alginate fiber nonwoven fabric 2 is prepared as the tissue permeation liquid absorption layer.

The chitosan-based drug-loaded composite antibacterial microfiber membrane 1 and the calcium alginate fiber nonwoven fabric 2 are bonded together using bioadhesive polyacrylic acid, and then the calcium alginate fiber nonwoven fabric 2 is coated with The polyethylene film of biological glue is finally covered with centrifugal paper on the antibacterial layer, and then cut at a speed of 200m/min to become an antibacterial composite wound dressing of a certain specification. The product has good antibacterial, hemostatic and wound-healing effects, as well as good air permeability and hygroscopicity. Among them, the determination of the antibacterial zone is that after the composite dressing is placed in the bacterial culture dish for 18-24 hours, it is tested at room temperature with a digital display vernier caliper immediately after it is taken out from the incubator. Staphylococcus aureus (SA) 22mm and Escherichia coli (EC) 24mm, as shown in sample No. 3 in Fig. 5 . The moisture absorption rate of the dressing is 2052.7%, the liquid retention rate is 723.7%, and the waterproof grade is 4.

Example 4

As shown in Figure 1, it is a schematic structural view of the antibacterial composite wound dressing of the present invention, and the antibacterial composite wound dressing includes a chitosan-based drug-loaded composite antibacterial microfiber membrane 1 sequentially arranged from top to bottom , calcium alginate fiber non-woven fabric 2 and support protection layer 3. The supporting protective layer 3 is polyacrylate pressure-sensitive adhesive.

The concrete steps of the preparation method of described antibacterial composite wound dressing are:

Add antibacterial drug powder moxifloxacin hydrochloride to 90% acetic acid aqueous solution by mass fraction, stir it with a magnetic stirrer to fully dissolve it, weigh chitosan and polyethylene oxide powder and add it to the above solution, and stir to obtain a uniform, stable spinning solution, the concentration of polyoxyethylene in the spinning solution is 0.5wt%, the weight ratio of chitosan and polyoxyethylene is 90:10, and the weight ratio of antibacterial drug and polyoxyethylene is 10:10 , under the conditions of spinning voltage of 16kv, spinning solution feed rate of 0.8mL/h, receiving distance of 20cm, ambient temperature of 25°C and relative humidity of 35%, electrospinning was carried out for 8h, and the prepared nano The fiber membrane was placed in a desiccator filled with 25% glutaraldehyde aqueous solution, cross-linked for 24 hours, and then dried in a vacuum oven for 24 hours to remove residual solvents and cross-linking agent glutaraldehyde, and finally protected from light in the desiccator save. The obtained chitosan-based drug-loaded composite antibacterial ultrafine fiber membrane has a fiber diameter of 280±50 nm and a drug-loading rate of 94%.

100% calcium alginate fibers are used to undergo opening, carding, web laying and spunlace in sequence. The process parameters of carding and web laying are: the feeding speed of the carding machine is 0.85m/min, the cylinder speed is 800m/min, and the output fiber web The speed is 55m/min, the laying speed is 55m/min, and the unevenness of the output fiber web is 3.5%. The process parameters of the spunlace are: the pressure of the pre-wet spunlace head is 30Pa, and the pressure of the spunlace head is 40 Pa, 40 Pa, 45Pa, 45Pa, the production speed of the spunlace machine is 20m/min, and the calcium alginate fiber nonwoven fabric 2 is prepared, which is used as the tissue permeation liquid absorption layer.

The chitosan-based drug-loaded composite antibacterial microfiber membrane 1 and the calcium alginate fiber nonwoven fabric 2 are bonded together using bioadhesive polyacrylic acid, and then polyacrylic acid is applied on the calcium alginate fiber nonwoven fabric 2 Ester pressure-sensitive adhesive, and finally, after covering the antibacterial layer with centrifugal paper, it is cut at a speed of 200m/min to become an antibacterial composite wound dressing of a certain specification. The product has good antibacterial, hemostatic and wound-healing effects, as well as good air permeability and hygroscopicity. Among them, the determination of the antibacterial zone is that after the composite dressing is placed in the bacterial culture dish for 18-24 hours, it is tested at room temperature with a digital display vernier caliper immediately after it is taken out from the incubator. Staphylococcus aureus (SA) 24mm and Escherichia coli (EC) 25mm. Its antibacterial effect is shown in No. 4 sample in Fig. 6. The dressing has a liquid absorption rate of 2607.3%, a liquid retention rate of 757%, and a waterproof grade of 5.

Claims (10)

1. an antibacterial composite wound dressing, is characterized in that, comprises the chitosan-based drug-loaded composite antibacterial microfiber film (1), calcium alginate fiber nonwoven fabric (2) and Support the protective layer (3). 2. antibacterial composite wound dressing as claimed in claim 1, is characterized in that, described support protective layer (3) is the nonwoven fabric of polyacrylate pressure-sensitive adhesive, polyurethane film, polyethylene film, polypropylene fiber , Non-woven fabrics of ethylene-propylene composite fibers or non-woven fabrics of a mixture of polypropylene fibers and ethylene-propylene composite fibers. 3. the preparation method of the antibacterial composite wound dressing described in claim 1 or 2, is characterized in that, concrete steps comprise: The first step: add antimicrobial drug powder into the aqueous solution of acetic acid with a mass fraction of 2-95%, stir it with a magnetic stirrer to make it fully dissolve, weigh chitosan and polyethylene oxide powder and add it to the above solution, and stir to obtain spinning Silk solution; under the conditions of spinning voltage of 8-30Kv, spinning solution feed rate of 0.08-1.2mL/h, receiving distance of 10-35cm, ambient temperature of 15-50°C and relative humidity of 20-60% Electrospinning is carried out under the environment, and the obtained nanofiber membrane is placed in a desiccator filled with 20-30% glutaraldehyde aqueous solution, cross-linked for 12-36 hours, and then dried in a vacuum oven for 12-36 hours to remove residual Solvent and cross-linking agent glutaraldehyde to obtain chitosan-based drug-loaded composite antibacterial microfiber membrane (1), the fiber diameter of which is 150-400nm; Step 2: Calcium alginate fiber is used, followed by opening, carding, web laying and spunlace in sequence to prepare calcium alginate fiber non-woven fabric (2), which is used as the absorption layer of tissue infiltration fluid; The third step: the chitosan-based drug-loaded composite antibacterial microfiber membrane (1) and the calcium alginate fiber non-woven fabric (2) are bonded together with a bioadhesive, and then bonded with the supporting protective layer (3) Composite, cut into a certain specification of antibacterial composite wound dressing. 4. the preparation method of antibacterial composite wound dressing as claimed in claim 3 is characterized in that, the concentration of polyoxyethylene in the spinning solution in the described first step is 0.3-0.6wt%, chitosan and poly The weight ratio of ethylene oxide is 10-93:10, and the weight ratio of antibacterial drug to polyethylene oxide is 5-15:10. 5. the preparation method of antibacterial composite wound dressing as claimed in claim 3 is characterized in that, the chitosan in the described first step is white powder, deacetylation degree＞95%, grade is medical grade, polyoxidized Ethylene is a white powder with a molecular weight of 400-1000KDa. 6. the preparation method of antibacterial compound type wound dressing as claimed in claim 3, is characterized in that, the antibacterial drug in the described first step is moxifloxacin hydrochloride, ciprofloxacin hydrochloride, mephifloxacin, levofloxacin hydrochloride Floxacin, amoxicillin, or tetracycline hydrochloride. 7. the preparation method of antibacterial composite wound dressing as claimed in claim 3 is characterized in that, the carding in the second step and laying process parameters are: carding machine feeding speed 0.2-0.9m/min, tin The forest speed is 500-900m/min, the output fiber web speed is 40-70m/min, the laying speed is 40-60m/min, and the unevenness of the output fiber web is 1.5-4%. 8. The preparation method of antibacterial composite wound dressing as claimed in claim 3, characterized in that, the cutting speed in the third step is 100-400m/min. 9. the preparation method of antibacterial composite wound dressing as claimed in claim 3 is characterized in that, the liquid absorption rate of gained antibacterial composite wound dressing is 500-2000%, and liquid retention rate is 600-1000%, antibacterial The ring diameter is 10-35mm. 10. The preparation method of antibacterial composite wound dressing according to claim 3, characterized in that, the drug loading rate of the chitosan-based drug-loaded composite antibacterial microfiber membrane (1) is 90-96%.