Antibacterial dressing for promoting wound healing, preparation method and application method

Abstract

The invention relates to the technical field of medical dressings, and discloses an antibacterial dressing for promoting wound healing, a preparation method, and an application. The invention forms a gel copolymer network with gelatin and a quaternary ammonium salt, and adds a long-chain polyhydroxy alcohol including at least 5 carbon atoms therein, and the alcohol hydroxyl groups of the long-chain polyhydroxy alcohol are used to impart water and oxygen adsorption properties to the hydrogel, thereby increasing the oxygen concentration at the wound, which is beneficial to promoting the healing of damaged tissues. The water and oxygen adsorption properties imparted by the long-chain polyhydroxy alcohol have the characteristics of good durability; at the same time, the long-chain polyhydroxy alcohol is grafted onto the quaternary ammonium salt methacryloyloxy dodecyl pyridine, which can improve the antibacterial activity of the quaternary ammonium hydrogel, thereby forming a dressing with high antibacterial activity, and avoiding invasive infection of the wound surface.

Description

Technical Field

[0001] The invention relates to the technical field of medical dressings, and in particular to an antibacterial dressing for promoting wound healing, a preparation method and an application method thereof. Background Art

[0002] The external tissues of the human body are important natural barriers that protect the normal functioning of the internal tissues. For example, scratches from sharp objects, abrasions from falls, or surgical wounds often cause external tissue damage. When external tissues are damaged, the wound is prone to bleeding, infection, or inflammation, which greatly affects the healing efficiency of the wound and even causes more serious complications. Dressings can form an acquired barrier at the wound, acting as an external tissue in time to resist the invasion of bacteria or viruses.

[0003] At present, relevant research based on hydrogel wound dressings is constantly advancing. For example, a Chinese patent with application publication number CN111905142A discloses an oxygen-releasing hydrogel dressing, which includes a first dressing and a second dressing, wherein the first dressing is prepared from a hydrogel dressing, glucose, an oxygen-releasing catalyst, and a polyester mesh with a pore structure, and the second dressing contains a hydrogel dressing and glucose oxidase. The patent uses the first dressing and the second dressing in combination so that the dressing can release oxygen after contacting the air when in use, thereby increasing the oxygen concentration of the wound surface and accelerating the healing speed of the wound. However, the dressing is provided with oxygen by the material of the dressing itself, and the oxygen it provides is limited, and the dressing needs to be changed frequently, and the drug compliance is low; and the mesh structure of the dressing is large and large, which easily leads to contact between bacteria in the air and the wound surface, but it does not take into account the antibacterial problem. Summary of the invention

[0004] In order to solve the above-mentioned dressing problem of external tissue damage, the present invention provides an antibacterial dressing, preparation method and dressing for promoting wound healing. The prior art hydrogel dressing has shortcomings in improving the oxygen concentration at the wound. The present invention forms a gel copolymer network with gelatin and quaternary ammonium salt, and adds a long-chain polyhydroxy alcohol including at least 5 carbons therein. The alcohol hydroxyl groups of the long-chain polyhydroxy alcohol give the hydrogel the ability to adsorb water and oxygen, which can increase the oxygen concentration at the wound and promote the healing of damaged external tissues. The water and oxygen adsorption properties given by the long-chain polyhydroxy alcohol have the characteristics of good durability; at the same time, the long-chain polyhydroxy alcohol is grafted on the quaternary ammonium salt methacryloyloxy dodecyl pyridine, which can improve the antibacterial activity of the quaternary ammonium hydrogel, and then a dressing with high antibacterial activity can be formed to avoid invasive infection of the wound surface.

[0005] The specific technical scheme of the present invention is:

[0006] In a first aspect, the present invention provides an antibacterial dressing for promoting wound healing, wherein the hydrogel dressing is obtained by copolymerization of a quaternary ammonium salt and gelatin, wherein:

[0007] During the copolymerization, a long-chain polyhydroxy alcohol is added, and the mass ratio of the quaternary ammonium salt to the long-chain polyhydroxy alcohol is 10:3-8;

[0008] The long-chain polyhydric alcohol comprises the structure: , the R group is an alkyl group comprising at least 5 carbons.

[0009] The present invention forms a gel copolymer network with gelatin and quaternary ammonium salt, and adds a long-chain polyhydroxy alcohol including at least 5 carbon atoms therein, and the alcoholic hydroxyl groups of the long-chain polyhydroxy alcohol are used to give the hydrogel water and oxygen adsorption properties, so that the oxygen concentration at the wound can be increased, which is conducive to promoting the healing of damaged tissues, and the water and oxygen adsorption properties given by the long-chain polyhydroxy alcohol have the characteristics of good durability. Quaternary ammonium salts are a class of antibacterial substances with broad-spectrum bactericidal properties. They not only have excellent antibacterial properties, but also have the advantages of strong permeability and lasting biological effects. The dressing of the present invention uses the quaternary ammonium salt and the long-chain polyhydroxy alcohol with a specific content as the active main body of the hydrogel dressing, so that the wound heals quickly and invasive infection can be avoided on the wound surface.

[0010] Preferably, the long-chain polyhydroxy alcohol is selected from one or more of the following alcohols:

[0011] 1,4-pentanediol, 1,5-pentanediol, 1,6-hexanediol, 1,5-hexanediol, 1,2-heptanediol, 1,7-heptanediol.

[0012] Preferably, the quaternary ammonium salt is methacryloyloxydodecylpyridinium.

[0013] The antibacterial activity of the quaternary ammonium hydrogel can be improved by grafting a long-chain polyhydroxy alcohol onto a quaternary ammonium salt of methacryloyloxy dodecyl pyridine, thereby forming a dressing with high antibacterial activity. The mass ratio of the quaternary ammonium salt of methacryloyloxy dodecyl pyridine to the long-chain polyhydroxy alcohol is 10:3-8. If the amount of the long-chain polyhydroxy alcohol added is too much, the mechanical strength of the hydrogel will be too low, which is not conducive to the durability of the hydrogel dressing; if the amount of the long-chain polyhydroxy alcohol added is too small, the antibacterial activity of the quaternary ammonium hydrogel cannot be improved.

[0014] In a second aspect, the present invention provides a method for preparing an antibacterial dressing for promoting wound healing, comprising the following steps:

[0015] Step S1: dissolving gelatin in a PBS solution to obtain a gelatin solution, then dropping methacrylic anhydride into the gelatin solution, and continuously stirring to obtain methacrylated gelatin;

[0016] Step S2: Methacryloyloxydodecylpyridine and long-chain polyhydroxy alcohol are mixed, ultrasonicated for a period of time, then added to the methacryl-acylated gelatin, a photosensitizer is added, and a reaction is initiated under ultraviolet light;

[0017] Step S3: freeze-drying the reaction solution and then thawing it, repeating this process 3 to 10 times to obtain a hydrogel.

[0018] The present invention prepares a gel network with gelatin hydrogel as a matrix through the above steps S1 to S3. The dressing of the present invention uses gelatin hydrogel as a gel matrix, and adds quaternary ammonium salt grafted long-chain polyhydroxy alcohol to the copolymer. The addition of a certain amount of long-chain polyhydroxy alcohol can enhance the performance of the gel in absorbing water and oxygen, and improve the mechanical strength of the gel. The gelatin hydrogel network prepared by the present invention can absorb and retain a large amount of water, and has good mechanical strength. The network structure can be maintained during water absorption during use, and a good healing environment with good wettability can be continuously provided for the wound. After absorbing water, the gel expands and a certain pressure can be formed at the wound. The micro-positive pressure can effectively avoid local edema, avoid excessive wound exudation caused by negative pressure, and promote wound healing.

[0019] Preferably, in step S1, the stirring temperature is 40-60° C., and the stirring time is 4-5 hours.

[0020] Preferably, in step S2, the mass ratio of methacryloyloxydodecylpyridine to the long-chain polyhydroxy alcohol is 10:3-8.

[0021] Preferably, the mass ratio of methacryloyloxydodecylpyridine to gelatin is 1:3-6.

[0022] Preferably, in step S2, the intensity of ultrasound is 30-50 W / m 2 The ultrasound time is 0.5~1 hour.

[0023] Preferably, in step S2, the photosensitizer is diacetophenone.

[0024] In a third aspect, the present invention provides a dressing, wherein the dressing uses medical cotton gauze as a carrier, and the preparation method of the dressing comprises the following steps: immersing the medical cotton gauze in the above-mentioned antibacterial dressing at 25-35°C for 12-24 hours.

[0025] Compared with the prior art, the present invention has the following technical effects:

[0026] (1) The present invention forms a gel copolymer network with gelatin and quaternary ammonium salt, and adds a long-chain polyhydroxy alcohol containing at least 5 carbon atoms therein, and endows the hydrogel with water and oxygen adsorption properties through the alcohol hydroxyl groups of the long-chain polyhydroxy alcohol, thereby increasing the oxygen concentration at the wound and facilitating the healing of damaged tissues. The water and oxygen adsorption properties imparted by the long-chain polyhydroxy alcohol are characterized by good durability. The present invention provides a new design and method for increasing the oxygen concentration at the wound.

[0027] (2) The present invention grafts long-chain polyhydroxy alcohol onto quaternary ammonium salt methacryloyloxy dodecyl pyridine, which can improve the antibacterial activity of quaternary ammonium saline gel, and further form a dressing with high antibacterial activity, which can prevent invasive infection after the wound surface contacts the air. The dressing can be used with a carrier with a large mesh structure and is suitable for dressing, repair and protection of general external tissue injuries.

[0028] (3) The dressing of the present invention has a gel network of gelatin hydrogel. The addition of long-chain polyhydroxy alcohol will give the gel water absorption properties. The gelatin hydrogel network prepared by the present invention can absorb and retain a large amount of water and has good mechanical strength. It can maintain the network structure while absorbing water during use, and can continuously provide a good healing environment with good moisturizing properties for the wound. After absorbing water, the gel expands and can form a certain pressure at the wound. This micro-positive pressure can effectively avoid local edema, avoid excessive wound exudation caused by negative pressure, and promote wound healing. DETAILED DESCRIPTION

[0029] The present invention provides an antibacterial dressing for promoting wound healing, which is obtained by copolymerization of quaternary ammonium salt and gelatin, wherein:

[0030] During the copolymerization, a long-chain polyhydroxy alcohol is added, and the mass ratio of the quaternary ammonium salt to the long-chain polyhydroxy alcohol is 10:3-8;

[0031] The long-chain polyhydric alcohol comprises the structure: , the R group is an alkyl group comprising at least 5 carbons.

[0032] The antibacterial dressing for promoting wound healing of the present invention forms a gel copolymerization network with gelatin and quaternary ammonium salt, and adds a long-chain polyhydroxy alcohol including at least 5 carbons therein, and the alcoholic hydroxyl groups of the long-chain polyhydroxy alcohol are used to give the hydrogel water and oxygen adsorption properties, so that the oxygen concentration at the wound can be increased, which is conducive to promoting the healing of damaged tissues, and the water and oxygen adsorption properties given by the long-chain polyhydroxy alcohol have the characteristics of good durability. Quaternary ammonium salts are a class of antibacterial substances with broad-spectrum bactericidal properties. They not only have excellent antibacterial properties, but also have the advantages of strong permeability and lasting biological effects. The dressing of the present invention uses the quaternary ammonium salt and the long-chain polyhydroxy alcohol with a specific content as the active main body of the hydrogel dressing, so that the wound heals quickly and invasive infection can be avoided on the wound surface.

[0033] The two ends of the long-chain polyhydroxy alcohol are alcohol hydroxyl groups, and the central alkyl group includes at least 5 carbon atoms, otherwise the formed hydrogel will have poor mechanical properties and the usability of the dressing will be reduced.

[0034] Preferably, the long-chain polyhydroxy alcohol is selected from one or more of the following alcohols:

[0035] 1,4-pentanediol, 1,5-pentanediol, 1,6-hexanediol, 1,5-hexanediol, 1,2-heptanediol, 1,7-heptanediol.

[0036] The antibacterial dressing for promoting wound healing of the present invention has one of its innovations, that is, the addition of long-chain polyhydroxy alcohol. The long-chain polyhydroxy alcohol added in the present invention has at least the following three functions: first, the end hydroxyl group absorbs moisture in the air, so that the dressing can continuously provide a good healing environment with good moisturizing properties for the wound, and after adsorption, the gel expands to form a certain micro-positive pressure at the wound site to avoid local edema; second, the hydrogel is endowed with a certain oxygen adsorption performance, the oxygen concentration of the damaged tissue is increased, and healing is promoted; third, the end hydroxyl group is grafted with a quaternary ammonium salt to increase the antibacterial activity of the quaternary ammonium salt and avoid wound infection. Comprehensively considering the above-mentioned multi-faceted effects of the long-chain polyhydroxy alcohol, the long-chain polyhydroxy alcohol added in the dressing of the present invention is preferably selected from one or more of 1,4-pentanediol, 1,5-pentanediol, 1,6-hexanediol, 1,5-hexanediol, 1,2-heptanediol, and 1,7-heptanediol. If the chain length is too long, it is difficult to improve the antibacterial activity of the quaternary ammonium salt. Further, it is preferably selected from 1,5-pentanediol, 1,6-hexanediol, and 1,7-heptanediol.

[0037] Preferably, the quaternary ammonium salt is methacryloyloxydodecylpyridinium.

[0038] The research team of the present invention has found in many practices that grafting long-chain polyhydroxy alcohols onto quaternary ammonium salt methacryloyloxy dodecyl pyridine can improve the antibacterial activity of quaternary ammonium hydrogel. The mass ratio of quaternary ammonium salt methacryloyloxy dodecyl pyridine to long-chain polyhydroxy alcohol is 10:3-8. If the amount of long-chain polyhydroxy alcohol added is too much, the mechanical strength of the hydrogel will be too small, which is not conducive to the durability of the hydrogel dressing; if the amount of long-chain polyhydroxy alcohol added is too small, the antibacterial activity of the quaternary ammonium hydrogel cannot be improved.

[0039] Specifically, for the above-mentioned antibacterial dressing for promoting wound healing, the present invention provides a preparation method, comprising the following steps:

[0040] Step S1: dissolving gelatin in a PBS solution to obtain a gelatin solution, then dropping methacrylic anhydride into the gelatin solution, and continuously stirring to obtain methacrylated gelatin;

[0041] Step S2: Methacryloyloxydodecylpyridine and long-chain polyhydroxy alcohol are mixed, ultrasonicated for a period of time, then added to the methacryl-acylated gelatin, a photosensitizer is added, and a reaction is initiated under ultraviolet light;

[0042] Step S3: freeze-drying the reaction solution and then thawing it, repeating this process 3 to 10 times to obtain a hydrogel.

[0043] Through the above steps S1 to S3, a gel network with gelatin hydrogel as a matrix is ​​prepared. The dressing of the present invention uses gelatin hydrogel as a gel matrix, and adds quaternary ammonium salt grafted long-chain polyhydroxy alcohol to the copolymer. The addition of a certain amount of long-chain polyhydroxy alcohol can enhance the performance of the gel in absorbing water and oxygen, and improve the mechanical strength of the gel. The gelatin hydrogel network prepared by the present invention can absorb and retain a large amount of water, and has good mechanical strength. It can maintain the network structure during water absorption during use, and can continuously provide a good healing environment with good wettability for the wound. After absorbing water, the gel expands and can form a certain pressure at the wound. This slight positive pressure can effectively avoid local edema, avoid excessive wound exudation caused by negative pressure, and promote wound healing.

[0044] Preferably, in step S1, the stirring temperature is 40-60° C., and the stirring time is 4-5 hours.

[0045] Preferably, in step S2, the mass ratio of methacryloyloxydodecylpyridine to the long-chain polyhydroxy alcohol is 10:3-8.

[0046] Preferably, the mass ratio of methacryloyloxydodecylpyridine to gelatin is 1:3-6.

[0047] Preferably, in step S2, the intensity of ultrasound is 30-50 W / m 2 The ultrasound time is 0.5~1 hour.

[0048] Preferably, in step S2, the photosensitizer is diacetophenone.

[0049] Specifically, with respect to the above-mentioned antibacterial dressing for promoting wound healing, the present invention provides a dressing, wherein the dressing uses medical cotton gauze as a carrier, and the preparation method of the dressing comprises the following steps: immersing the medical cotton gauze in the above-mentioned antibacterial dressing at 25-35°C for 12-24 hours.

[0050] The present invention will be further described below in conjunction with embodiments. Those of ordinary skill in the art will be able to implement the present invention based on these descriptions. In addition, the embodiments of the present invention involved in the following description are generally only embodiments of a part of the present invention, rather than all embodiments. Therefore, based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work should belong to the scope of protection of the present invention.

[0051] Embodiment 1:

[0052] This embodiment provides a hydrogel dressing, which is prepared according to the following steps:

[0053] Step S1: Calculated by weight, 40 parts of gelatin are added to 120 parts of PBS solution with a pH of 7.0, and the temperature is heated to 55° C. and stirred for 4.5 hours to obtain a gelatin solution. Then, 100 parts of methacrylic anhydride are dropped into the gelatin solution and stirred continuously to obtain methacrylated gelatin.

[0054] Step S2: 10 parts of methacryloyloxy dodecyl pyridine and 6 parts of 1,6-hexanediol were mixed and heated at an intensity of 40 W / m 2 After ultrasonic treatment for 1 hour, the mixture was added to the methacrylated gelatin, and 0.5 parts of diphenylacetophenone was added, and then a cross-linking reaction was initiated under ultraviolet light.

[0055] Step S3: freeze-dry the reaction solution at -30°C, then thaw it, repeat the freezing and thawing process 4 times to obtain a hydrogel dressing.

[0056] Embodiment 2:

[0057] This embodiment provides a hydrogel dressing, which is prepared according to the following steps:

[0058] Step S1: Calculated by weight, 30 parts of gelatin are added to 105 parts of PBS solution with a pH of 7.0, heated to 40°C, and stirred for 5 hours to obtain a gelatin solution, and then 100 parts of methacrylic anhydride are dropped into the gelatin solution, and stirred continuously to obtain methacrylated gelatin.

[0059] Step S2: 10 parts of methacryloyloxy dodecyl pyridine and 3 parts of 1,6-hexanediol were mixed and heated at an intensity of 30 W / m 2 After ultrasonic treatment for 1 hour, the mixture was added to the methacrylated gelatin, and 0.5 parts of diphenylacetophenone was added, and then a cross-linking reaction was initiated under ultraviolet light.

[0060] Step S3: freeze-dry the reaction solution at -30°C, then thaw it, repeat the freezing and thawing process for 5 times to obtain a hydrogel dressing.

[0061] Embodiment 3:

[0062] This embodiment provides a hydrogel dressing, which is prepared according to the following steps:

[0063] Step S1: Calculated by weight, 60 parts of gelatin are added to 130 parts of PBS solution with a pH of 7.0, heated to 60°C, and stirred for 4 hours to obtain a gelatin solution, and then 100 parts of methacrylic anhydride are dropped into the gelatin solution, and stirred continuously to obtain methacrylated gelatin.

[0064] Step S2: 10 parts of methacryloyloxy dodecyl pyridine and 8 parts of 1,6-hexanediol were mixed and heated at an intensity of 50 W / m 2 After ultrasonic treatment for 0.5 h, the mixture was added to the methacrylated gelatin, and 0.5 parts of diphenylacetophenone was added, and then a cross-linking reaction was initiated under ultraviolet light.

[0065] Step S3: freeze-dry the reaction solution at -30°C, then thaw it, repeat the freezing and thawing process for 3 times to obtain a hydrogel dressing.

[0066] Embodiment 4:

[0067] This embodiment provides a hydrogel dressing, and the specific preparation steps are different from those in Example 1, except that 1,4-pentanediol is added instead of 1,6-hexanediol. Other operations are the same as those in Example 1.

[0068] Embodiment 5:

[0069] This embodiment provides a hydrogel dressing, and the specific preparation steps are different from those in Example 1, except that 1,5-pentanediol is added instead of 1,6-hexanediol. Other operations are the same as those in Example 1.

[0070] Embodiment 6:

[0071] This embodiment provides a hydrogel dressing, and the specific preparation steps are different from those in Example 1, except that 1,6-hexanediol is not added, but 1,5-hexanediol is added instead. Other operations are the same as those in Example 1.

[0072] Embodiment 7:

[0073] This embodiment provides a hydrogel dressing, and the specific preparation steps are different from those in Example 1, except that 1,2-heptanediol is added instead of 1,6-hexanediol. Other operations are the same as those in Example 1.

[0074] Embodiment 8:

[0075] This embodiment provides a hydrogel dressing, and the specific preparation steps are different from those in Example 1, except that 1,6-hexanediol is not added, but 1,7-heptanediol is added instead. Other operations are the same as those in Example 1.

[0076] Comparative Example 1

[0077] This comparative example provides a hydrogel dressing, and the specific preparation steps are different from those of Example 1, except that 1,6-hexanediol is not added. Other operations are the same as those of Example 1.

[0078] Comparative Example 2

[0079] This comparative example provides a hydrogel dressing, and the specific preparation steps are different from those of Example 1, except that 1,3-propylene glycol is added instead of 1,6-hexanediol. Other operations are the same as those of Example 1.

[0080] Comparative Example 3

[0081] This comparative example provides a hydrogel dressing, and the specific preparation steps are different from those of Example 1, except that 1,8-octanediol is added instead of 1,6-hexanediol. Other operations are the same as those of Example 1.

[0082] Comparative Example 4

[0083] This comparative example provides a hydrogel dressing, and the specific preparation steps are different from those of Example 1, except that 1.5 parts of 1,6-hexanediol are added. Other operations are the same as those of Example 1.

[0084] Comparative Example 5

[0085] This comparative example provides a hydrogel dressing, and the specific preparation steps are different from those of Example 1, except that 1,6-hexanediol is added in 10 parts. Other operations are the same as those of Example 1.

[0086] Comparative Example 6

[0087] This comparative example provides a hydrogel dressing, and the specific preparation steps are different from those of Example 1, except that: step S2 does not perform ultrasound, but is replaced by stirring at a rate of 800 rpm for 1 hour. Other operations are the same as those of Example 1.

[0088] Performance Characterization

[0089] The tensile strength and antibacterial rate of the hydrogel dressings prepared in Examples 1 to 8 and Comparative Examples 1 to 6 were tested, and the results are shown in Table 1. The antibacterial rate was tested by the coating plate method, specifically, the incubated bacterial suspension was inoculated onto the surface of the solid nutrient culture medium, the number of colonies was counted after cultivation, and the antibacterial rate was calculated according to the number of colonies. Antibacterial rate calculation formula: Antibacterial rate = [(average number of colonies in the control sample - average number of colonies in the test sample) / average number of colonies in the control sample] × 100%.

[0090] Table 1

[0091]

[0092] From Table 1, we can see that:

[0093] (1) The hydrogel dressing of the present invention uses gelatin hydrogel as the gel matrix, and adds a long-chain polyhydroxy alcohol grafted with a quaternary ammonium salt to the copolymer. The mechanical strength of the hydrogel obtained is good. The long-chain polyhydroxy alcohol is grafted on the quaternary ammonium salt methacryloyloxy dodecyl pyridine, which can improve the antibacterial activity of the quaternary ammonium hydrogel. Quaternary ammonium salt is a kind of antibacterial substance with broad-spectrum bactericidal properties. The dressing of the present invention uses quaternary ammonium salt and a specific content of long-chain polyhydroxy alcohol as the active body of the hydrogel dressing, which can promote wound healing and prevent invasive infection of the wound surface.

[0094] (2) By comparing and analyzing Comparative Examples 2 and 3 with Example 1, and combining with Examples 4 to 8, it can be seen that the alkyl chain length of the middle part of the long-chain polyhydroxy alcohol added to the dressing of the present invention will have a certain effect on the performance of the hydrogel dressing. When the chain length is too short or too long, the antibacterial activity of the quaternary ammonium salt cannot be improved. At the same time, the alkyl chain length in the middle part will also affect the mechanical strength of the hydrogel. For example, when 1,3-propylene glycol is added to Comparative Example 2, when the chain length is too short, it may not provide skeleton strength for the gel network, and due to its liquid properties, it may affect the cross-linking reaction, so the tensile strength becomes low; when 1,8-octanediol is added to Comparative Example 3, when the chain length is too long, the long-chain polyhydroxy alcohol is difficult to participate in the cross-linking reaction, and thus the mechanical strength of the hydrogel cannot be effectively improved. Taking all factors into consideration, the long-chain polyhydroxy alcohol added to the dressing of the present invention is preferably one or more of 1,4-pentanediol, 1,5-pentanediol, 1,6-hexanediol, 1,5-hexanediol, 1,2-heptanediol, and 1,7-heptanediol. Further, it is preferably selected from 1,5-pentanediol, 1,6-hexanediol, and 1,7-heptanediol.

[0095] (3) By comparing comparative examples 4 and 5 with Example 1, the addition amount of long-chain polyhydroxy alcohol will affect the performance of the hydrogel dressing prepared by the present invention. Comparative analysis shows that the mass ratio of quaternary ammonium salt methacryloyloxy dodecyl pyridine to long-chain polyhydroxy alcohol is 10:3-8. If the addition amount of long-chain polyhydroxy alcohol is too much, the mechanical strength of the hydrogel will be too small, which is not conducive to the durability of the hydrogel dressing; if the addition amount of long-chain polyhydroxy alcohol is too small, the antibacterial activity of the quaternary ammonium hydrogel cannot be improved.

[0096] (4) By comparing comparative example 6 with example 1, it is found that ultrasound is beneficial for grafting long-chain polyhydroxy alcohol onto quaternary ammonium salt methacryloyloxy dodecyl pyridine, which is beneficial for improving the antibacterial activity of methacryloyloxy dodecyl pyridine, thereby improving the antibacterial activity of quaternary ammonium salt gel.

[0097] The raw materials and equipment used in the present invention, unless otherwise specified, are all commonly used raw materials and equipment in the art; the methods used in the present invention, unless otherwise specified, are all conventional methods in the art.

[0098] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent transformation made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. An antibacterial dressing for promoting wound healing, characterized in that: The antibacterial dressing is obtained by copolymerization of quaternary ammonium salt and gelatin, wherein: During the copolymerization, a long-chain polyhydroxy alcohol is added, and the mass ratio of the quaternary ammonium salt to the long-chain polyhydroxy alcohol is 10:3-8; the long-chain polyhydroxy alcohol comprises a structure: HO-R-OH, and the R group is an alkyl group including at least 5 carbon atoms; The long-chain polyhydroxy alcohol is selected from one or more of the following alcohols: 1,4-pentanediol, 1,5-pentanediol, 1,6-hexanediol, 1,5-hexanediol, 1,2-heptanediol, 1,7-heptanediol; The quaternary ammonium salt is methacryloyloxy dodecyl pyridine.

2. The method for preparing the antibacterial dressing according to claim 1, characterized in that: The following steps are involved: Step S1: dissolving gelatin in a PBS solution to obtain a gelatin solution, then dropping methacrylic anhydride into the gelatin solution, and continuously stirring to obtain methacrylated gelatin; Step S2: Methacryloyloxydodecylpyridine and long-chain polyhydroxy alcohol are mixed, ultrasonicated for a period of time, then added to the methacryl-acylated gelatin, a photosensitizer is added, and a reaction is initiated under ultraviolet light; Step S3: freeze-drying the reaction solution and then thawing it, repeating the process 3 to 10 times to obtain a hydrogel; In step S2, the intensity of ultrasound is 30 to 50 W / m 2 The ultrasound time is 0.5 to 1 hour.

3. The preparation method according to claim 2, characterized in that: In step S1, the stirring temperature is 40-60°C, and the stirring time is 4-5 hours.

4. The preparation method according to claim 2, characterized in that: In step S2, the mass ratio of methacryloyloxydodecylpyridine to the long-chain polyhydroxy alcohol is 10:3-8.

5. The preparation method according to claim 2, characterized in that: The mass ratio of methacryloyloxydodecylpyridine to gelatin is 1:3-6.

6. The preparation method according to claim 2, characterized in that: In step S2, the photosensitizer is diacetophenone.

7. A patch, characterized in that: The dressing uses medical cotton gauze as a carrier, and the preparation method of the dressing comprises the following steps: dipping the medical cotton gauze in the antibacterial dressing according to claim 1 or the antibacterial dressing prepared by the preparation method according to claim 2, and dipping at 25 to 35° C. for 12 to 24 hours.

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