CN112295009A

CN112295009A - Long-acting humidity-controlling antibacterial dressing and preparation method and application thereof

Info

Publication number: CN112295009A
Application number: CN202011137104.9A
Authority: CN
Inventors: 廖志星
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-10-22
Filing date: 2020-10-22
Publication date: 2021-02-02

Abstract

The invention belongs to the technical field of medical supplies, and particularly relates to a long-acting humidity-control antibacterial dressing and a preparation method and application thereof. Firstly, modifying chondroitin sulfate by using anhydride to obtain modified chondroitin sulfate, and then loading nano zinc oxide on the modified chondroitin sulfate to obtain a chondroitin sulfate compound; then adding the natural collagen into the aqueous solution containing the chondroitin sulfate compound, and carrying out modification treatment to obtain modified collagen; then mixing the modified collagen and the glycidol modified silk fibroin to prepare spinning solution, and performing electrostatic spinning to obtain a fiber membrane; and finally, crosslinking the interior of the fibrous membrane under the crosslinking action of procyanidine and dialdehyde sodium carboxymethyl cellulose to obtain the long-acting humidity-controlling antibacterial dressing. The dressing has good long-acting humidity control effect, and has excellent antibacterial performance and mechanical performance.

Description

Long-acting humidity-controlling antibacterial dressing and preparation method and application thereof

Technical Field

The invention belongs to the technical field of medical supplies. More particularly, relates to a long-acting humidity-controlling antibacterial dressing and a preparation method and application thereof.

Background

Local wound and bleeding, infection and ulcer caused by the local wound are common injuries, the integrity of skin is damaged, the barrier capability of normally defending bacteria is lost, necrotic tissues of the wound and exudates containing a large amount of protein are good culture media for bacterial reproduction, and under the action of various factors, the wound is easy to generate local infection and even cause systemic infection, and finally the healing time is prolonged.

The dressing is a medical material which is widely applied clinically and used for covering wounds and the like. The traditional dressings mainly comprise natural gauze, synthetic fiber inner dressings, foaming polymer dressings, hydrocolloid dressings and the like. The traditional gauze dressing can not keep the wound surface moist, prevent the tissue cells from epithelization and delay the wound surface healing; dressing fibers are easy to fall off, foreign body reaction is caused, and healing is affected; the granulation tissue of the wound surface is easy to grow into meshes of the dressing to be adhered, and the new epithelium and granulation tissue are often damaged during dressing change to cause bleeding, so that the wound healing is not facilitated, and the pain of a patient is difficult to endure; the water absorption is not strong, the hemostatic effect is not good, and pathogens easily permeate gauze to infect wounds; the workload of dressing change is large. Overall, there are three challenges to be addressed in wound healing: constantly exuding tissue fluids, risk of bacterial infection and a slightly moist environment conducive to wound healing. Therefore, an ideal wound dressing should not only effectively absorb the tissue exudate, but also ensure the wound surface to have certain humidity, and have antibacterial property to prevent wound infection.

The hydrogel is a macromolecule with a three-dimensional space structure formed by cross-linking hydrophilic macromolecular compounds among molecules. Because of the peculiar hydrophilic structure of the hydrogel macromolecules, a large amount of water can be absorbed and retained in the hydrogel structure, and therefore, the hydrogel has good water absorption and retention properties. Compared with other dressings, the hydrogel dressing has unique advantages that the hydrogel dressing can prevent excessive loss of moisture and body fluid to achieve the effect of hemostasis; the antibacterial and anti-inflammatory fabric has good permeability to water and oxygen, can resist bacterial invasion to a certain extent and inhibit the growth of bacteria, and has the functions of antibiosis and antiphlogosis; the adhesive can be well attached to the wound surface, but cannot be adhered to the wound surface so as to avoid secondary injury caused by dressing replacement; the wound surface is in a moist environment without effusion, has good biocompatibility and can promote wound healing. But the composite material has the defect of poor mechanical property, is often fixed during application, causes inconvenience, has poor antibacterial property and cannot meet the requirement of clinical application.

Disclosure of Invention

The invention aims to solve the technical problem of overcoming the defects and defects of poor antibacterial performance and mechanical performance of the conventional hydrogel dressing and provides a long-acting humidity-controlling antibacterial dressing as well as a preparation method and application thereof.

The invention aims to provide a long-acting humidity-controlling antibacterial dressing.

The invention also aims to provide a preparation method of the long-acting humidity-control antibacterial dressing.

The invention also aims to provide application of the long-acting humidity-control antibacterial dressing as a medical dressing for skin wounds.

The above purpose of the invention is realized by the following technical scheme:

a preparation method of a long-acting humidity-control antibacterial dressing comprises the following specific steps:

(1) firstly, modifying chondroitin sulfate by using anhydride to obtain modified chondroitin sulfate, and then loading nano zinc oxide on the modified chondroitin sulfate to obtain a chondroitin sulfate compound;

(2) then adding the natural collagen into the aqueous solution containing the chondroitin sulfate compound, and carrying out modification treatment to obtain modified collagen;

(3) then mixing the modified collagen and the glycidol modified silk fibroin to prepare spinning solution, and performing electrostatic spinning to obtain a fiber membrane;

(4) and finally, crosslinking the interior of the fiber membrane under the crosslinking action of procyanidine and dialdehyde sodium carboxymethyl cellulose to obtain the long-acting humidity-controlling antibacterial dressing.

Preferably, in the step (1), the chondroitin sulfate is selected from any one or more of pig chondroitin sulfate, cow chondroitin sulfate, shark chondroitin sulfate, chicken chondroitin sulfate, duck chondroitin sulfate, cuttlefish chondroitin sulfate, sturgeon chondroitin sulfate, eel chondroitin sulfate, ray chondroitin sulfate and stingray chondroitin sulfate.

Preferably, in the step (1), the modified chondroitin sulfate is prepared by the following steps: adding 1 part of chondroitin sulfate into 5-8 parts of water, stirring until the chondroitin sulfate is completely dissolved, then stirring and heating to 45-55 ℃, adding 1-1.2 parts of anhydride while stirring, keeping the temperature and stirring for 2-3 hours, and carrying out vacuum freeze drying to obtain the modified chondroitin sulfate.

Further preferably, the acid anhydride is selected from any one of maleic anhydride, succinic anhydride or glutaric anhydride.

Preferably, in the step (1), the specific method for loading the nano zinc oxide is as follows: adding 1 part of modified chondroitin sulfate into 8-10 parts of methanol solution containing 0.01-0.02 mol/L zinc acetate, stirring and reacting for 2-3 hours at 40-50 ℃, then adding 8-10 parts of methanol solution containing 0.02-0.03 mol/L sodium hydroxide, stirring and reacting for 3-4 hours at 40-50 ℃, and carrying out vacuum freeze drying to obtain the chondroitin sulfate compound.

Preferably, the specific method of the step (2) comprises the following steps in parts by weight: adding 1 part of chondroitin sulfate compound into 8-10 parts of acetic acid-sodium acetate buffer solution with the pH value of 4, uniformly oscillating by ultrasonic waves to obtain an aqueous solution, adding 3-5 parts of natural collagen into the aqueous solution, stirring at 8-10 ℃ for 25-32 hours, and carrying out vacuum freeze drying to obtain the modified collagen.

Further preferably, the natural collagen is selected from any one of porcine collagen and bovine collagen.

Preferably, the specific method of step (3) is as follows, in parts by weight: adding 1 part of modified collagen and 0.2-0.3 part of glycidol modified silk fibroin into 15-20 parts of deionized water, stirring for 30-35 hours at 8-10 ℃ to obtain spinning solution, and then performing electrostatic spinning to obtain the fiber membrane.

Further preferably, the process conditions of electrospinning are as follows: the positive voltage is 15-16 kV, the negative voltage is-0.1 to-0.15 kV, the flow rate of the spinning solution is 0.2-0.3 mm/min, and the receiving distance is 10-15 cm.

Preferably, in the step (3), the glycidyl modified silk fibroin is prepared by the following method in parts by weight: adding 1 part of silk fibroin, 0.1-0.2 part of glycidol and 0.1-0.2 part of sodium chloride into 8-10 parts of deionized water, stirring until the silk fibroin is completely dissolved, stirring at 60-65 ℃ for reaction for 2-3 hours, naturally cooling to room temperature (25 ℃), and soaking and washing with the deionized water for 2-4 days to remove unreacted substances, thus obtaining the glycidol modified silk fibroin.

Preferably, the specific method of the step (4) comprises the following steps in parts by weight: adding 1 part of procyanidine and 0.2-0.3 part of dialdehyde sodium carboxymethyl cellulose into 130-150 parts of deionized water, uniformly oscillating with ultrasonic waves, immersing 8-10 parts of fiber membrane in the deionized water, stirring at 8-10 ℃ for 5-8 hours, taking out, washing with deionized water, and sterilizing to obtain the long-acting humidity-controlling antibacterial dressing.

Further preferably, the preparation method of the dialdehyde sodium carboxymethyl cellulose refers to patent CN 104711702B.

The invention also aims to provide the long-acting humidity-controlling antibacterial dressing prepared by the preparation method.

The invention has the following beneficial effects:

firstly, modifying chondroitin sulfate by using anhydride to obtain modified chondroitin sulfate, and then loading nano zinc oxide on the modified chondroitin sulfate to obtain a chondroitin sulfate compound; then adding the natural collagen into the aqueous solution containing the chondroitin sulfate compound, and carrying out modification treatment to obtain modified collagen; then mixing the modified collagen and the glycidol modified silk fibroin to prepare spinning solution, and performing electrostatic spinning to obtain a fiber membrane; and finally, crosslinking the interior of the fibrous membrane under the crosslinking action of procyanidine and dialdehyde sodium carboxymethyl cellulose to obtain the long-acting humidity-controlling antibacterial dressing. The dressing has good long-acting humidity control effect, and has excellent antibacterial performance and mechanical performance.

Among them, chondroitin sulfate is an acidic mucopolysaccharide which contributes to improvement of blood circulation, acceleration of metabolism, promotion of absorption of a penetrant and elimination of inflammation, and has natural compatibility when applied to skin wounds. According to the invention, the modified chondroitin sulfate is obtained by modifying chondroitin sulfate with anhydride, and then the modified chondroitin sulfate is loaded with nano zinc oxide with an antibacterial effect, so that the antibacterial performance of the dressing is enhanced by the synergistic effect of the modified chondroitin sulfate and the nano zinc oxide. Moreover, the nano zinc oxide is coordinated and combined with carboxylic acid, so that the bonding stability is strong, and the mechanical property of the product is ensured. The chondroitin sulfate is characterized by extremely easy water absorption and strong water locking capability, and is also beneficial to ensuring the long-acting moisture control effect of the dressing.

The natural collagen has good biocompatibility but poor mechanical property, and the natural collagen and the glycidol modified silk fibroin are mixed to prepare spinning solution, and the spinning solution is prepared into a fiber membrane through electrostatic spinning, so that the mechanical property of the dressing is greatly improved. Meanwhile, the silk fibroin has a certain antibacterial property, and is interwoven with natural collagen to form a film, so that the antibacterial property of the dressing is improved.

According to the invention, procyanidine and dialdehyde sodium carboxymethyl cellulose are used as cross-linking agents, so that collagen and the like in a fibrous membrane are cross-linked, a three-dimensional network structure is favorably formed, the mechanical strength of the dressing is further improved, pores are enriched, and the long-acting humidity control performance and the antibacterial performance are further improved.

Detailed Description

The present invention is further illustrated by the following specific examples, which are not intended to limit the invention in any way. Reagents, methods and apparatus used in the present invention are conventional in the art unless otherwise indicated.

Unless otherwise indicated, reagents and materials used in the following examples are commercially available.

Example 1

In the step (1), the chondroitin sulfate is porcine chondroitin sulfate.

In the step (1), the preparation method of the modified chondroitin sulfate comprises the following steps: adding 1kg of chondroitin sulfate into 5kg of water, stirring until the chondroitin sulfate is completely dissolved, then stirring and heating to 55 ℃, adding 1kg of anhydride while stirring, keeping the temperature and stirring for 3 hours, and carrying out vacuum freeze drying to obtain the modified chondroitin sulfate.

The anhydride is maleic anhydride.

In the step (1), the specific method for loading the nano zinc oxide is as follows: adding 1kg of modified chondroitin sulfate into 8kg of methanol solution containing 0.02mol/L zinc acetate, stirring and reacting for 3 hours at 40 ℃, then adding 8kg of methanol solution containing 0.03mol/L sodium hydroxide, stirring and reacting for 4 hours at 40 ℃, and carrying out vacuum freeze drying to obtain the chondroitin sulfate compound.

The specific method of the step (2) is as follows: adding 1kg of chondroitin sulfate compound into 8kg of acetic acid-sodium acetate buffer solution with the pH value of 4, uniformly oscillating by ultrasonic waves to obtain an aqueous solution, adding 5kg of natural collagen into the aqueous solution, stirring at 8 ℃ for 32 hours, and carrying out vacuum freeze drying to obtain the modified collagen.

The natural collagen is porcine collagen.

The specific method of the step (3) is as follows: adding 1kg of modified collagen and 0.2kg of glycidol modified silk fibroin into 20kg of deionized water, stirring for 35 hours at 8 ℃ to obtain spinning solution, and then carrying out electrostatic spinning to obtain the fiber membrane.

The process conditions of electrostatic spinning are as follows: the positive voltage is 15kV, the negative voltage is-0.15 kV, the flow rate of the spinning solution is 0.2mm/min, and the receiving distance is 15 cm.

In the step (3), the glycidol modified silk fibroin is prepared by the following method: adding 1kg of silk fibroin, 0.1kg of glycidol and 0.2kg of sodium chloride into 8kg of deionized water, stirring until the silk fibroin is completely dissolved, stirring and reacting for 2 hours at 65 ℃, naturally cooling to room temperature (25 ℃), and soaking and washing with the deionized water for 4 days to remove unreacted substances, thereby obtaining the glycidol modified silk fibroin.

The specific method of the step (4) is as follows: adding 1kg of procyanidine and 0.2kg of dialdehyde sodium carboxymethyl cellulose into 150kg of deionized water, uniformly oscillating by ultrasonic waves, immersing 8kg of fiber membrane in the deionized water, stirring for 5 hours at 10 ℃, taking out, washing by the deionized water, and sterilizing to obtain the long-acting humidity-controlling antibacterial dressing.

The preparation method of the dialdehyde sodium carboxymethyl cellulose comprises the following steps: pouring 2kg of sodium carboxymethylcellulose and 20L of acetic acid-sodium acetate buffer solution with the pH value of 5.0 into a reaction kettle at the same time, stirring at room temperature until the solution is clear, dissolving 0.5kg of sodium periodate in 4L of the buffer solution, slowly pouring the solution into the reaction kettle, stirring at the temperature of 25 ℃ for reaction for 72 hours, adding 0.1L of polyethylene glycol serving as a reaction terminator after the reaction is finished, slowly stirring for 1 hour, then adding 2kg of sodium chloride and 100L of acetone into the reaction kettle, standing to precipitate, removing a supernatant, and finally centrifuging, washing, dialyzing, and freeze-drying to obtain the dialdehyde sodium carboxymethylcellulose.

Example 2

In the step (1), the chondroitin sulfate is duck chondroitin sulfate.

In the step (1), the preparation method of the modified chondroitin sulfate comprises the following steps: adding 1kg of chondroitin sulfate into 8kg of water, stirring until the chondroitin sulfate is completely dissolved, then stirring and heating to 45 ℃, adding 1.2kg of anhydride while stirring, keeping the temperature and stirring for 2 hours, and carrying out vacuum freeze drying to obtain the modified chondroitin sulfate.

Further preferably, the acid anhydride is succinic anhydride.

In the step (1), the specific method for loading the nano zinc oxide is as follows: adding 1kg of modified chondroitin sulfate into 10kg of methanol solution containing 0.01mol/L zinc acetate, stirring and reacting for 2 hours at 50 ℃, then adding 10kg of methanol solution containing 0.02mol/L sodium hydroxide, stirring and reacting for 3 hours at 50 ℃, and carrying out vacuum freeze drying to obtain the chondroitin sulfate compound.

The specific method of the step (2) is as follows: adding 1kg of chondroitin sulfate compound into 10kg of acetic acid-sodium acetate buffer solution with the pH value of 4, uniformly oscillating by ultrasonic waves to obtain an aqueous solution, adding 3kg of natural collagen into the aqueous solution, stirring at 10 ℃ for 25 hours, and carrying out vacuum freeze drying to obtain the modified collagen.

The natural collagen is bovine collagen.

The specific method of the step (3) is as follows: adding 1kg of modified collagen and 0.3kg of glycidol modified silk fibroin into 15kg of deionized water, stirring for 30 hours at 10 ℃ to obtain spinning solution, and then carrying out electrostatic spinning to obtain the fiber membrane.

The process conditions of electrostatic spinning are as follows: the positive voltage is 16kV, the negative voltage is-0.1 kV, the flow rate of the spinning solution is 0.3mm/min, and the receiving distance is 10 cm.

In the step (3), the glycidol modified silk fibroin is prepared by the following method: adding 1kg of silk fibroin, 0.2kg of glycidol and 0.1kg of sodium chloride into 10kg of deionized water, stirring until the silk fibroin is completely dissolved, stirring and reacting for 3 hours at 60 ℃, naturally cooling to room temperature (25 ℃), and soaking and washing with the deionized water for 2 days to remove unreacted substances, thus obtaining the glycidol modified silk fibroin.

The specific method of the step (4) is as follows: firstly, adding 1kg of procyanidine and 0.3kg of dialdehyde sodium carboxymethyl cellulose into 130kg of deionized water, carrying out ultrasonic oscillation uniformly, then immersing 10kg of fiber membrane into the mixture, stirring the mixture for 8 hours at the temperature of 8 ℃, taking the mixture out, washing the mixture with the deionized water, and carrying out disinfection and sterilization to obtain the long-acting humidity control antibacterial dressing.

The preparation method of the dialdehyde sodium carboxymethyl cellulose comprises the following steps: pouring 1kg of sodium carboxymethylcellulose and 50L of acetic acid-sodium acetate buffer solution with the pH value of 3.0 into a reaction kettle at the same time, stirring at room temperature until the solution is clear, dissolving 2kg of sodium periodate in 1L of the buffer solution, slowly pouring the solution into the reaction kettle, stirring at the temperature of 35 ℃ for reaction for 48 hours, adding 1L of polyethylene glycol serving as a reaction terminator after the reaction is finished, slowly stirring for 0.5 hour, then adding 5kg of sodium chloride and 30L of acetone into the reaction kettle, standing to precipitate, removing a supernatant, and finally centrifuging, washing, dialyzing, and freeze-drying to obtain the dialdehyde sodium carboxymethylcellulose.

Example 3

In the step (1), the chondroitin sulfate is ray chondroitin sulfate.

In the step (1), the preparation method of the modified chondroitin sulfate comprises the following steps: adding 1kg of chondroitin sulfate into 7kg of water, stirring until the chondroitin sulfate is completely dissolved, then stirring and heating to 50 ℃, adding 1.1kg of anhydride while stirring, keeping the temperature and stirring for 2.5 hours, and carrying out vacuum freeze drying to obtain the modified chondroitin sulfate.

Further preferably, the acid anhydride is glutaric anhydride.

In the step (1), the specific method for loading the nano zinc oxide is as follows: adding 1kg of modified chondroitin sulfate into 9kg of methanol solution containing 0.015mol/L zinc acetate, stirring and reacting for 2.5 hours at 45 ℃, then adding 9kg of methanol solution containing 0.025mol/L sodium hydroxide, stirring and reacting for 3.5 hours at 45 ℃, and carrying out vacuum freeze drying to obtain the chondroitin sulfate compound.

The specific method of the step (2) is as follows: adding 1kg of chondroitin sulfate compound into 9kg of acetic acid-sodium acetate buffer solution with the pH value of 4, uniformly oscillating by ultrasonic waves to obtain an aqueous solution, adding 4kg of natural collagen into the aqueous solution, stirring at 9 ℃ for 28 hours, and carrying out vacuum freeze drying to obtain the modified collagen.

The natural collagen is porcine collagen.

The specific method of the step (3) is as follows: adding 1kg of modified collagen and 0.25kg of glycidol modified silk fibroin into 18kg of deionized water, stirring for 32 hours at 9 ℃ to obtain spinning solution, and then carrying out electrostatic spinning to obtain the fiber membrane.

The process conditions of electrostatic spinning are as follows: the positive voltage is 16kV, the negative voltage is-0.12 kV, the flow rate of the spinning solution is 0.25mm/min, and the receiving distance is 12 cm.

In the step (3), the glycidol modified silk fibroin is prepared by the following method: adding 1kg of silk fibroin, 0.15kg of glycidol and 0.15kg of sodium chloride into 9kg of deionized water, stirring until the silk fibroin, the glycidol and the sodium chloride are completely dissolved, stirring and reacting for 2.5 hours at 62 ℃, naturally cooling to room temperature (25 ℃), and soaking and washing with the deionized water for 3 days to remove unreacted substances, thus obtaining the glycidol modified silk fibroin.

The specific method of the step (4) is as follows: adding 1kg of procyanidine and 0.25kg of dialdehyde sodium carboxymethyl cellulose into 140kg of deionized water, uniformly oscillating by ultrasonic waves, immersing 9kg of fiber membrane into the mixture, stirring for 7 hours at 9 ℃, taking out, washing by the deionized water, and sterilizing to obtain the long-acting humidity-controlling antibacterial dressing.

The preparation method of the dialdehyde sodium carboxymethyl cellulose comprises the following steps: pouring 1.5kg of sodium carboxymethylcellulose and 40L of acetic acid-sodium acetate buffer solution with the pH value of 4.0 into a reaction kettle at the same time, stirring at room temperature until the solution is clear, dissolving 1kg of sodium periodate in 3L of the buffer solution, slowly pouring the solution into the reaction kettle, stirring at the temperature of 30 ℃ for reaction for 60 hours, adding 0.8L of polyethylene glycol serving as a reaction terminator after the reaction is finished, slowly stirring for 0.8 hour, adding 4kg of sodium chloride and 60L of acetone into the reaction kettle, standing to precipitate, removing a supernatant, and finally centrifuging, washing, dialyzing, and freeze-drying to obtain the dialdehyde sodium carboxymethylcellulose.

Comparative example 1

(1) firstly, mixing natural collagen and glycidol modified silk fibroin to prepare spinning solution, and performing electrostatic spinning to obtain a fiber membrane;

(2) and then, under the crosslinking action of procyanidine and dialdehyde sodium carboxymethyl cellulose, crosslinking is carried out inside the fiber membrane to obtain the long-acting humidity-controlling antibacterial dressing.

The specific method of the step (1) is as follows: adding 1kg of natural collagen and 0.2kg of glycidol modified silk fibroin into 20kg of deionized water, stirring for 35 hours at 8 ℃ to obtain spinning solution, and then carrying out electrostatic spinning to obtain the fiber membrane.

In the step (1), the glycidol modified silk fibroin is prepared by the following method: adding 1kg of silk fibroin, 0.1kg of glycidol and 0.2kg of sodium chloride into 8kg of deionized water, stirring until the silk fibroin is completely dissolved, stirring and reacting for 2 hours at 65 ℃, naturally cooling to room temperature (25 ℃), and soaking and washing with the deionized water for 4 days to remove unreacted substances, thereby obtaining the glycidol modified silk fibroin.

The specific method of the step (2) is as follows: adding 1kg of procyanidine and 0.2kg of dialdehyde sodium carboxymethyl cellulose into 150kg of deionized water, uniformly oscillating by ultrasonic waves, immersing 8kg of fiber membrane in the deionized water, stirring for 5 hours at 10 ℃, taking out, washing by the deionized water, and sterilizing to obtain the long-acting humidity-controlling antibacterial dressing.

Comparative example 2

(3) preparing the modified collagen into spinning solution, and performing electrostatic spinning to obtain a fibrous membrane;

In the step (1), the chondroitin sulfate is porcine chondroitin sulfate.

The anhydride is maleic anhydride.

The natural collagen is porcine collagen.

The specific method of the step (3) is as follows: adding 1kg of modified collagen into 20kg of deionized water, stirring for 35 hours at 8 ℃ to obtain a spinning solution, and then carrying out electrostatic spinning to obtain the fiber membrane.

Comparative example 3

(4) and finally, crosslinking the interior of the fiber membrane under the crosslinking action of procyanidine to obtain the long-acting humidity-controlling antibacterial dressing.

In the step (1), the chondroitin sulfate is porcine chondroitin sulfate.

The anhydride is maleic anhydride.

The natural collagen is porcine collagen.

The specific method of the step (4) is as follows: adding 1kg of procyanidine into 150kg of deionized water, uniformly oscillating by ultrasonic waves, immersing 8kg of fiber membrane in the deionized water, stirring for 5 hours at 10 ℃, taking out, washing by the deionized water, and sterilizing to obtain the long-acting humidity-controlling antibacterial dressing.

Test examples

1. The humidity control effect is as follows:

and (3) testing conditions are as follows: at 37 ℃, the swelling degree is (Wt-Wo)/Wo, where Wt is the weight of the dressing at which swelling equilibrium is reached and Wo is the weight of the dried dressing. The moisture control effect of the dressings obtained in examples 1-3 and comparative examples 1-3 was examined with reference to the swelling and drug release performance of NIPAAm-based copolymerized temperature-sensitive gel (Panchun, Shi, Longqingde, et al, school of the university of south and China (Nature science edition), 2007, 38 (5): 906-911), and the results are shown in Table 1.

TABLE 1 moisture control Effect examination

As can be seen from Table 1, the dressings obtained in examples 1 to 3 can achieve the swelling equilibrium in a short period of time, have a high degree of swelling, and have a long retention time of the swelling equilibrium.

Comparative example 1 step (1) was omitted, and the natural collagen was not modified with chondroitin sulfate complex, and the moisture control performance of the obtained dressing was significantly deteriorated; comparative example 2 in step (3), glycidol modified silk fibroin is omitted, cross-linking synergy between proteins is lacked, and the moisture control performance of the dressing is obviously deteriorated; in the comparative example 3, the dialdehyde sodium carboxymethyl cellulose is omitted in the step (4), and the protein crosslinking is insufficient only by the crosslinking action of the procyanidin, so that the humidity control performance of the product is influenced.

2. Mechanical properties:

the tensile strength of the dressings obtained in examples 1 to 3 and comparative examples 1 to 3 was measured by an extensional rheometer, and the results are shown in Table 2.

A tensile strength σ t ═ p/(b × d), where σ t is a tensile strength (MPa); p is the maximum load (N); b is the specimen width (mm); d is the specimen thickness (mm).

TABLE 2 tensile Strength comparison

Sample (I)	Tensile Strength (MPa)
		Example 1	8.22
Example 2	8.28
		Example 3	8.34
Comparative example 1	6.11
		Comparative example 2	4.56
Comparative example 3	5.24

As is clear from Table 2, the dressings obtained in examples 1 to 3 had high tensile strength and excellent mechanical properties.

Comparative example 1 step (1) was omitted, and the chondroitin sulfate complex was not added to modify the native collagen, and the mechanical properties and the like of the obtained dressing were significantly deteriorated; in the comparative example 2, the glycidol modified silk fibroin is omitted in the step (3), the cross-linking synergy among the proteins is lacked, and the mechanical properties and the like of the dressing are obviously poor; in the comparative example 3, the dialdehyde sodium carboxymethyl cellulose is omitted in the step (4), and the protein crosslinking is insufficient only by the crosslinking action of the procyanidin, so that the mechanical properties of the product are influenced.

3. Antibacterial property:

evaluation of textile antibacterial properties according to GB/T20944.3-2008, part 3: the antibacterial performance of the dressing of the invention is measured by a vibration bottle method. The strains are Candida albicans and Escherichia coli, and the concentration of the bacteria liquid is 10⁵～10⁷cfu/mL. Firstly, adding buffered normal saline and a dressing product into a triangular flask, sterilizing for 20min in 0.1MPa steam at 121 ℃ and cooling to room temperature, transferring 1mL of bacterial liquid by using a 1mL sterile graduated pipette, and adding the bacterial liquid into the triangular flask. To force the sample into contact with the bacteria, the shaker was shaken for several hours at 37 ℃. 0.1mL of the solution before and after shaking was applied to nutrient agar medium, incubated at 37 ℃ for 24 hours, and compared, the results are shown in Table 3.

TABLE 3 comparison of antibacterial Properties

Sample (I)	Candida albicans inhibitory rate (%)	Escherichia coli inhibitory rate (%)
			Example 1	≥99.9	≥99.9
Example 2	≥99.9	≥99.9
			Example 3	≥99.9	≥99.9
Comparative example 1	94.8	95.1
			Comparative example 2	93.2	93.8
Comparative example 3	96.2	97.1

As can be seen from Table 3, the dressings obtained in examples 1 to 3 have a high bacteriostatic rate against Candida albicans and Escherichia coli.

Comparative example 1 step (1) was omitted, and the natural collagen was not modified with chondroitin sulfate complex, and the antibacterial property of the obtained dressing was significantly deteriorated; in the comparative example 2, the glycidol modified silk fibroin is omitted in the step (3), the cross-linking synergy among the proteins is lacked, and the antibacterial performance of the dressing is obviously poor; in the comparative example 3, the dialdehyde sodium carboxymethyl cellulose is omitted in the step (4), and the protein crosslinking is insufficient only by the crosslinking action of the procyanidin, so that the antibacterial performance of the product is influenced.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.

Claims

1. A preparation method of a long-acting humidity-control antibacterial dressing is characterized by comprising the following specific steps:

2. The method according to claim 1, wherein in the step (1), the modified chondroitin sulfate is prepared by the following method in parts by weight: adding 1 part of chondroitin sulfate into 5-8 parts of water, stirring until the chondroitin sulfate is completely dissolved, then stirring and heating to 45-55 ℃, adding 1-1.2 parts of anhydride while stirring, keeping the temperature and stirring for 2-3 hours, and carrying out vacuum freeze drying to obtain the modified chondroitin sulfate.

3. The method according to claim 2, wherein the acid anhydride is selected from any one of maleic anhydride, succinic anhydride, and glutaric anhydride.

4. The preparation method according to claim 1, wherein in the step (1), the specific method for loading the nano zinc oxide is as follows in parts by weight: adding 1 part of modified chondroitin sulfate into 8-10 parts of methanol solution containing 0.01-0.02 mol/L zinc acetate, stirring and reacting for 2-3 hours at 40-50 ℃, then adding 8-10 parts of methanol solution containing 0.02-0.03 mol/L sodium hydroxide, stirring and reacting for 3-4 hours at 40-50 ℃, and carrying out vacuum freeze drying to obtain the chondroitin sulfate compound.

5. The preparation method according to claim 1, wherein the specific method of the step (2) comprises the following steps in parts by weight: adding 1 part of chondroitin sulfate compound into 8-10 parts of acetic acid-sodium acetate buffer solution with the pH value of 4, uniformly oscillating by ultrasonic waves to obtain an aqueous solution, adding 3-5 parts of natural collagen into the aqueous solution, stirring at 8-10 ℃ for 25-32 hours, and carrying out vacuum freeze drying to obtain the modified collagen.

6. The preparation method according to claim 1, wherein the specific method of step (3) is as follows, in parts by weight: adding 1 part of modified collagen and 0.2-0.3 part of glycidol modified silk fibroin into 15-20 parts of deionized water, stirring for 30-35 hours at 8-10 ℃ to obtain spinning solution, and then performing electrostatic spinning to obtain the fiber membrane.

7. The preparation method of claim 1, wherein in the step (3), the glycidyl modified silk fibroin is prepared by the following method in parts by weight: adding 1 part of silk fibroin, 0.1-0.2 part of glycidol and 0.1-0.2 part of sodium chloride into 8-10 parts of deionized water, stirring until the silk fibroin is completely dissolved, stirring at 60-65 ℃ for reaction for 2-3 hours, naturally cooling to room temperature, and soaking and washing with deionized water for 2-4 days to remove unreacted substances, thus obtaining the glycidol modified silk fibroin.

8. The preparation method according to claim 1, wherein the specific method of the step (4) comprises the following steps in parts by weight: adding 1 part of procyanidine and 0.2-0.3 part of dialdehyde sodium carboxymethyl cellulose into 130-150 parts of deionized water, uniformly oscillating with ultrasonic waves, immersing 8-10 parts of fiber membrane in the deionized water, stirring at 8-10 ℃ for 5-8 hours, taking out, washing with deionized water, and sterilizing to obtain the long-acting humidity-controlling antibacterial dressing.

9. A long-acting humidity-controlling antibacterial dressing obtained by the preparation method of any one of claims 1-8.

10. Use of a long-acting moisture-controlling antimicrobial dressing according to claim 9 as a medical dressing for skin wounds.