Antibacterial and antioxidant hydrogel as well as preparation method and application thereof

Abstract

The invention belongs to the field of polymer composite materials, and particularly relates to antibacterial and antioxidant hydrogel and a preparation method and application thereof.The preparation method includes the following steps that S1, a carboxymethyl chitosan solution and an acrylamide solution are prepared and mixed to be uniform, then an acryloyloxyethyl trimethyl ammonium chloride solution is added, and a mixed solution is obtained; s2, adding a cross-linking agent, an initiator and a catalyst into the mixed solution obtained in the step S1, uniformly mixing, and ultrasonically defoaming to obtain a hydrogel precursor; s3, the hydrogel precursor obtained in the step S2 is subjected to swelling through a polyphenol compound, and the hydrogel is obtained. Compared with the prior art, the problems that hydrogel disclosed in the prior art is insufficient in antibacterial and anti-oxidation effect, clinical infection is likely to be caused and the like are solved, polyphenol compounds are further introduced into the hydrogel, and the antibacterial and anti-oxidation functions are greatly improved.

Description

Technical Field

[0001] The invention belongs to the field of polymer composite materials, and specifically relates to an antibacterial and antioxidant hydrogel and a preparation method and application thereof. Background Art

[0002] Skin tissue is one of the most important organs in the human body. It is an irreplaceable barrier to maintain the normal function of the body and plays an important role in protecting the body from external damage. Once the skin is damaged, it is easy to be invaded by microorganisms in a short period of time. It is difficult to recover through the body's self-repair mechanism, which brings continuous pain and burden to patients, and there is also the risk of further infection and deterioration. At present, antibiotics are usually used to treat wounds in clinical practice, but the abuse of antibiotics can cause bacteria to develop drug resistance. The increase in drug-resistant bacteria will bring huge challenges to the use of drugs by medical staff. Therefore, it is imperative to explore a material that is easy to obtain, biocompatible and antibacterial.

[0003] Hydrogels are considered to be an effective alternative to conventional dressings because of their good liquid absorption capacity, moisturizing effect and cool skin touch. At present, many researchers have applied hydrogels to wound dressings, but the main research focuses on mechanical strength, while there are few studies on functionalized hydrogels or the results are insufficient. Therefore, based on the research deficiencies in the prior art, the inventors proposed an antibacterial and antioxidant hydrogel. Summary of the invention

[0004] The purpose of the present invention is to provide an antibacterial and antioxidant hydrogel and its preparation method and application in order to solve at least one of the above problems, so as to solve the problems that the hydrogel disclosed in the prior art has insufficient antibacterial and antioxidant effects and is easy to cause clinical infection. The present solution further introduces polyphenol compounds into the hydrogel to achieve a significant improvement in the antibacterial and antioxidant functions.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] The first aspect of the present invention discloses a method for preparing an antibacterial and antioxidant hydrogel, comprising the following steps:

[0007] S1: preparing a carboxymethyl chitosan solution and an acrylamide solution respectively, mixing them evenly, and then adding an acryloyloxyethyl trimethyl ammonium chloride solution to obtain a mixed solution;

[0008] S2: adding a crosslinking agent, an initiator and a catalyst to the mixed solution obtained in step S1, mixing well and then ultrasonically degassing to obtain a hydrogel precursor;

[0009] S3: Swelling the hydrogel precursor obtained in step S2 with a polyphenol compound to obtain the hydrogel.

[0010] Preferably, the concentration of the carboxymethyl chitosan solution is 0.5-2 wt %; the mass concentration of the acrylamide solution is 0.1-0.5 g / mL; and the concentration of the acryloyloxyethyl trimethyl ammonium chloride solution is 0.5-2 wt %.

[0011] Preferably, the volume ratio of the carboxymethyl chitosan solution to the acrylamide solution is 1:1 to 1:3, and the volume ratio of the acryloyloxyethyl trimethyl ammonium chloride solution to the acrylamide solution is 0.2:1 to 0.25:1.

[0012] Preferably, the cross-linking agent is N,N-methylenebisacrylamide, the initiator is ammonium persulfate, and the catalyst is N,N,N',N'-tetramethylethylenediamine.

[0013] Preferably, the mass ratio of the crosslinking agent to acrylamide in the acrylamide solution is 0.001:1 to 0.002:1, the mass ratio of the initiator to acrylamide in the acrylamide solution is 1:10 to 1.5:10, and the volume ratio of the catalyst to the mixed solution is 0.5:1000 to 1:1000.

[0014] Preferably, the polyphenolic compound is one or more of tannic acid, quercetin, curcumin and proanthocyanidins, and the concentration of the polyphenolic compound is 0.1-0.4 wt %.

[0015] Preferably, the usage ratio of the polyphenol compound to the hydrogel precursor is 100-500 μL:0.1 g.

[0016] Preferably, the mixing in step S1 is performed in an ice bath.

[0017] The second aspect of the present invention discloses an antibacterial and antioxidant hydrogel, which is obtained by any of the above-mentioned preparation methods.

[0018] The third aspect of the present invention discloses the use of the antibacterial and antioxidant hydrogel as described above as a dressing.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The present invention provides an antibacterial and antioxidant hydrogel, a preparation method and application thereof, such as a wound dressing. The hydrogel provided by the present invention can stably combine two polymers with different properties and functions, thereby achieving complementary properties between the components. Carboxymethyl chitosan (QCS) has good solubility and excellent antibacterial ability. Compared with ordinary chitosan, the positive charge of QCS is greatly improved, which can give it excellent antibacterial properties and has strong competitiveness in the application of wound dressings. At the same time, the polyphenol compounds used in the present invention, such as proanthocyanidins, are a general term for a large class of polyphenol compounds widely present in plants, and have strong antioxidant and free radical elimination effects. The present invention combines the two to provide an antibacterial and antioxidant hydrogel. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The antibacterial performance test diagram of Examples 1 to 4 and the control group;

[0022] Figure 2 This is a graph showing the determination of the antibacterial rate of Escherichia coli in Examples 1 to 4;

[0023] Figure 3 The graphs for determining the antibacterial rate of Staphylococcus aureus in Examples 1 to 4 are as follows;

[0024] Figure 4 DPPH free radical scavenging ability diagram of Examples 4 to 7;

[0025] Figure 5 ABTS free radical scavenging ability diagram of Examples 4 to 7;

[0026] Figure 6 is a graph of the hydroxyl radical scavenging ability of Examples 4 to 7;

[0027] Figure 7 It is the total reducing power measurement diagram of Examples 4 to 7;

[0028] Figure 8 The sodium hyaluronate enzyme inhibition test of Examples 4 to 7;

[0029] Fig. 9 The cytotoxicity effect diagrams of Examples 4 to 7 are shown. DETAILED DESCRIPTION

[0030] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. The specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. The principles and features of the present invention are described below, and the examples cited are only used to explain the present invention and are not intended to limit the scope of the present invention. In the embodiments, unless otherwise specified, the conditions recommended by the manufacturer or the manufacturer are followed. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products that can be purchased commercially.

[0031] In order to make up for the shortcomings of existing antibacterial dressings, the purpose of the present invention is to provide a hydrogel with excellent antibacterial ability and antioxidant properties, and a preparation method and application thereof.

[0032] The present invention provides the following technical solutions:

[0033] The hydrogel is prepared by mixing carboxymethyl chitosan, acrylamide monomer and a cross-linking agent to form a hydrogel, and polyphenol compounds such as tannic acid, quercetin, curcumin and proanthocyanidins can be further incorporated into the hydrogel network through swelling.

[0034] The preparation method of the hydrogel comprises the following steps:

[0035] (1) Carboxymethyl chitosan and acrylamide are added to deionized water respectively and stirred to obtain carboxymethyl chitosan (QCS) and acrylamide (AM) solutions, which are then mixed with acryloyloxyethyl trimethyl ammonium chloride solution (DAC) in a certain proportion.

[0036] (2) Add N,N-methylenebisacrylamide as a crosslinking agent, ammonium persulfate as an initiator, and N,N,N',N'-tetramethylethylenediamine as a catalyst to the above-mentioned mixed solution, mix well and perform ultrasonic degassing, put into a mold, take a certain amount of polyphenol compound powder to prepare a solution of a certain concentration and swell it, so as to obtain an antibacterial, antioxidant, and adhesive multifunctional hydrogel dressing.

[0037] Specifically, the polyphenol compound may be proanthocyanidin, and the resulting hydrogel is: carboxymethyl chitosan-proanthocyanidin-polyacrylamide hydrogel, referred to as QCS-OPC-PAM hydrogel;

[0038] In one embodiment of the present invention, the concentration of the carboxymethyl chitosan solution in step (1) is 0.5-2 wt%, preferably 2 wt%.

[0039] In one embodiment of the present invention, the amount of the acrylamide solution in step (1) is 0.1-0.5 g / mL, preferably 0.18 g / mL.

[0040] In one embodiment of the present invention, the concentration of the acryloyloxyethyltrimethylammonium chloride solution in step (1) is 0.5-1 wt %, preferably 1 wt %.

[0041] In one embodiment of the present invention, the volume ratio of the carboxymethyl chitosan solution to the acrylamide solution in step (1) is 1:1 to 1:3, and the volume ratio of the acryloyloxyethyl trimethyl ammonium chloride solution to the acrylamide solution is 0.2:1 to 0.25:1.

[0042] In one embodiment of the present invention, the mass ratio of N,N-methylenebisacryloyl to acrylamide in step (2) is 0.001:1 to 0.002:1, preferably 0.001:1.

[0043] In one embodiment of the present invention, the mass ratio of ammonium persulfate to acrylamide in step (2) is 1:10 to 1.5:10, preferably 1:10.

[0044] In one embodiment of the present invention, the volume ratio of the N,N,N',N'-tetramethylethylenediamine in step (2) to the mixed solution is 0.5:1000 to 1:1000, preferably 0.5:1000.

[0045] In one embodiment of the present invention, the concentration of the polyphenol compound in step (2) is 0.1 wt% to 0.4 wt%, preferably 0.4 wt%.

[0046] In one embodiment of the present invention, the stirring condition in step (2) is an ice bath, and after being stirred evenly, the mixture is placed into a mold and ultrasonically degassed to form a hydrogel.

[0047] The present invention provides an antibacterial and antioxidant hydrogel, a preparation method and application thereof, such as for use as a wound dressing. The hydrogel provided by the present invention can stably combine two polymers with different properties and functions, thereby achieving complementary properties between the components. Carboxymethyl chitosan (QCS) has good solubility and excellent antibacterial ability. Compared with conventional chitosan, the positive charge of QCS is greatly improved, giving it excellent antibacterial properties, and it has strong competitiveness in the application of wound dressings. At the same time, the polyphenol compounds used in the present invention are a general term for a large class of polyphenol compounds widely present in plants, which have strong antioxidant and free radical elimination effects. The present invention combines the two to provide an antibacterial and antioxidant hydrogel.

[0048] The hydrogel obtained by the invention has good antioxidant properties, excellent antibacterial ability and soothing effect, is easy to peel off after being treated with a sodium bicarbonate solution, and can provide a good wound surface microenvironment.

[0049] Example 1

[0050] An antibacterial and antioxidant hydrogel and a preparation method thereof, comprising the following steps:

[0051] (1) Dissolve 0.1 g of carboxymethyl chitosan in 5 mL of deionized water to obtain a 2 wt% quaternary ammonium salt chitosan solution; dissolve 1.8 g of acrylamide in 4 mL of deionized water to prepare a 0.45 g / mL acrylamide solution; mix the prepared quaternary ammonium salt chitosan solution and acrylamide solution, stir evenly to obtain a mixed solution, and then add 1 mL of acryloyloxyethyl trimethyl ammonium chloride solution and mix evenly.

[0052] (2) In the above 10 mL mixed solution, 0.0018 g of N,N-methylenebisacrylamide was used as a cross-linking agent, 0.18 g of ammonium persulfate was used as an initiator, and 5 μL of N,N,N',N'-tetramethylethylenediamine was used as a catalyst. The mixture was stirred evenly in an ice bath and then ultrasonically degassed. The mixture was then placed in a cylindrical mold to obtain a polymer composite hydrogel named 1QCS-PAM hydrogel.

[0053] Example 2

[0054] After obtaining the hydrogel in step (2) of Example 1, 1 mg of proanthocyanidin (OPC) was dissolved in 1 mL of deionized water to obtain an OPC solution. 100 μL of the OPC solution was added to every 0.1 g of the hydrogel for swelling. Other conditions remained unchanged to obtain an antibacterial and antioxidant polymer composite hydrogel: 1QCS-1OPC-PAM hydrogel.

[0055] Example 3

[0056] The weight of carboxymethyl chitosan in step (1) of Example 1 was changed to 0.2 g while other conditions remained unchanged to obtain 2QCS-PAM hydrogel.

[0057] Example 4

[0058] After obtaining the hydrogel according to the steps of Example 3, 1 mg of proanthocyanidin (OPC) was dissolved in 1 mL of deionized water to obtain an OPC solution. 100 μL of the OPC solution was added to every 0.1 g of the hydrogel for swelling, and other conditions remained unchanged to obtain a 2QCS-1OPC-PAM hydrogel.

[0059] Example 5

[0060] The weight of proanthocyanidins in Example 4 was changed to 2 mg, while other conditions remained unchanged, to obtain 2QCS-2OPC-PAM hydrogel.

[0061] Example 6

[0062] The weight of proanthocyanidins in Example 4 was changed to 3 mg, and other conditions remained unchanged to obtain 2QCS-3OPC-PAM hydrogel.

[0063] Example 7

[0064] The weight of proanthocyanidins in Example 4 was changed to 4 mg, while other conditions remained unchanged, to obtain 2QCS-4OPC-PAM hydrogel.

[0065] 1. Determination of antibacterial properties:

[0066] Experiment: The antibacterial properties of the hydrogels were quantitatively evaluated using the shake flask method. The cylindrical samples were cut into 0.1 g pieces and sterilized with UV light. Two bacteria (E. coli and S. aureus) were cultured in nutrient broth for 24 hours at a shaking speed of 130 rpm and a temperature of 37°C. The bacterial growth was diluted with sterile PBS solution to a test bacterial density range of 1×10 8 Up to 5×10 8 CFU / mL. Subsequently, the hydrogel samples (Examples 1 to 4) and 2 mL of bacterial suspension were cultured in an oscillator at 24±1°C and 150 r / min for 18 to 24 hours. Afterwards, the cultured mixed solution was taken out and graded diluted with PBS (10 1 , 10 2 , 10 3 , 10 4 , 10 5 and 10 6 20 μL of each gradient dilution solution was dropped into a sterile culture dish containing solidified agar medium and incubated at 37°C for 24 h, and the colony forming units (CFU) were counted.

[0067] The control group, without the addition of hydrogel samples, was cultured under the same conditions.

[0068] Each group was repeated three times, and the antibacterial performance test of the samples was calculated according to the following equation:

[0069]

[0070] Among them A b is the number of surviving bacteria in the blank control group, A S is the number of viable bacteria in the sample group.

[0071] The results are as follows Figures 1 to 3 As shown. Figures 1 to 3 It can be seen that when the concentration of carboxymethyl chitosan in the hydrogel sample increases, the inhibition rate of the hydrogel on Escherichia coli and Staphylococcus aureus increases accordingly. After adding proanthocyanidins at the same time, the inhibition rate of the hydrogel on Escherichia coli and Staphylococcus aureus increases accordingly, and there is an obvious synergistic effect. Compared with the control group, the highest inhibition rates of Examples 1 to 4 on Escherichia coli and Staphylococcus aureus can reach 93.27% and 94.97%, respectively, with excellent antibacterial effects.

[0072] 2. Antioxidant Determination:

[0073] 1) DPPH free radical scavenging rate determination

[0074] Weigh 2 mg of DPPH powder and dissolve it in 40 mL of 95% ethanol solution. Ultrasonicate for 15 min to mix the DPPH solution evenly. After the ultrasonication, take 2 mL of the solution and measure its absorbance at 517 nm. Adjust the absorbance of the DPPH solution to between 1.2 and 1.3.

[0075] The hydrogels of Examples 4 to 7 were cut into slices and immersed in an ethanol solution with a solid dispersion weight of 10% w / v. Finally, the hydrogel dispersion and the DPPH solution were mixed in equal volumes. The mixture was incubated in the dark for 1 hour, and the optical density of the mixture was measured at 517 nm using a microplate reader. DPPH free radical scavenging ability DPPH scavenging rate was calculated by the following formula:

[0076]

[0077] Where: A 1 is the absorbance of blank (DPPH+ethanol), A 0 is the absorbance of the hydrogel test product (DPPH+ethanol+hydrogel sample).

[0078] The results are as follows Figure 4 As shown. Figure 4 It can be seen that when the concentration of proanthocyanidins in the hydrogel sample increases, the DPPH scavenging rate increases with the increase of the proanthocyanidin concentration. When the concentration is the highest, the scavenging rate can reach up to 77.94%. Therefore, the hydrogel has a certain antioxidant effect.

[0079] 2) ABTS free radical scavenging rate determination

[0080] Mix 5 mL of 7.4 mmol / L ABTS stock solution with 88 μL of 2.6 mmol / L K 2 S 2 O 8 Mix and let stand for 12-16 hours to prepare ABTS working solution. Take 0.4 mL of ABTS solution and dilute with PBS solution. The absorbance value at room temperature is 734 nm.

[0081] 2 mL of ABTS and 0.5 g of each hydrogel of Examples 4 to 7 were mixed and placed in the dark at room temperature for 10 min. The absorbance at a wavelength of 734 nm was measured three times in parallel at room temperature. The scavenging ability of the hydrogel sample for ABTS free radicals was calculated by the following formula:

[0082]

[0083] Where: A 0 is the absorbance of the sample without hydrogel and with ABTS added; A 1is the absorbance of the hydrogel sample and ABTS.

[0084] The results are as follows Figure 5 As shown. Figure 5 It can be seen that when the concentration of proanthocyanidins in the hydrogel sample increases, the ABTS clearance rate increases with the increase of proanthocyanidins concentration. When the concentration is the highest, the clearance rate can reach up to 82.18%, so the hydrogel has a certain antioxidant effect.

[0085] 3) Determination of hydroxyl radical scavenging rate

[0086] Take 1g of hydrogel sample (Examples 4-7) and add 3mL 2mmol / L FeSO 4 Solution and 3mL 6mmol / L salicylic acid solution in a test tube, shake well, add 3mL 1mmol / LH 2 O 2 Start, heat to 37℃, time 30min, take out, adjust the wavelength of the spectrophotometer to 510nm and measure the absorbance value; use 3mL deionized water instead of 3mL 1mmol / LH 2 O 2 As the background of the test solution, measure the absorbance value; use 1mL of deionized water instead of the sample solution as the blank control. Measure the absorbance with deionized water as the reference, and calculate the scavenging ability of the hydrogel sample for hydroxyl free radicals using the following formula:

[0087] Hydroxyl radical scavenging rate = [1-(A 1 -A 2 )÷A 0 ]×100%

[0088] Where: A 0 is the absorbance value of blank control; A 1 A is the absorbance value of the sample solution; 2 is the background absorbance value of the test solution.

[0089] The results are as follows Figure 6 As shown. Figure 6 It can be seen that when the concentration of proanthocyanidins in the sample increases, the hydroxyl radical scavenging rate increases with the increase of proanthocyanidins concentration. When the concentration is the highest, the scavenging rate can reach up to 99.74%, so the hydrogel has a certain antioxidant effect.

[0090] 4) Determination of iron ion reducing antioxidant capacity

[0091] Take 0.2g of hydrogel sample (Examples 4-7), add 0.5mL of phosphate buffer solution (pH=7.2) and 1% potassium ferricyanide solution, keep in a water bath at 50℃ for 20min, and terminate the reaction in an ice bath. Add 0.5mL of 10% trichloroacetic acid solution and rotate at 3000r / min. -1 Centrifuge for 10 minutes, take the supernatant and divide it into two parts, a and b. Add 1.7 mL of distilled water and 0.17 mL of 0.1% ferric chloride solution to part b, let it stand for 10 minutes, and measure the absorbance of b at a wavelength of 70 nm, which is A. 1 , a sample is the control group, and its absorbance is A 2 The blank group is 0.2g hydrogel sample replaced by 0.2g deionized water, and the other conditions are the same as those of sample a. Its absorbance is A 0 Each group of tests was repeated 3 times in parallel, and the experimental results were averaged. The formula for calculating the total reducing power is as follows: The formula for the moisturizing rate is as follows:

[0092] A 0 =(a 1 -a 2 -a 3 )×100%

[0093] Where: A 1 is the absorbance of the sample; A 2 is the absorbance of the control; A 3 is the absorbance of the blank group.

[0094] The results are as follows Figure 7 As shown, from Figure 7 It can be seen that when the concentration of proanthocyanidins in the sample increases, the clearance rate increases with the increase of the proanthocyanidin concentration. When the concentration is the highest, the clearance rate can reach up to 73.85%. Therefore, the hydrogel has a certain antioxidant effect.

[0095] 5) Determination of hyaluronidase inhibition rate:

[0096] 0.1 mL of 12.5 mM calcium chloride solution, 0.05 mL of hyaluronidase solution and 0.1 g of hydrogel sample (Examples 4 to 7) were added to 1.5 mL centrifuge tubes, respectively, and recorded as T; 0.1 mL of 2.5 mM calcium chloride solution, 0.05 mL of acetic acid buffer solution and 0.1 mL of sample solution were added to 1.5 mL centrifuge tubes, respectively, and recorded as T 0 ; 0.1 mL of 12.5 mM calcium chloride solution, 0.05 mL of hyaluronidase solution and 0.1 mL of solvent were added to a 1.5 mL centrifuge tube, respectively, and the mixture was recorded as C; 0.1 mL of 12.5 mM calcium chloride solution, 0.05 mL of phosphate buffer solution and 0.1 mL of solvent were added to a 15 mL centrifuge tube, respectively, and the mixture was recorded as C 0After keeping at 37℃ for 40min, add 0.2mL sodium hyaluronate to T and C. 0 With C 0 0.2 mL of distilled water was added. After keeping the mixture at 37°C for 60 min, 0.1 mL of sodium hydroxide and acetylacetone solution were added. After boiling in a water bath for 10 min, 0.5 mL of p-dimethylaminobenzaldehyde was added. After keeping the mixture at 37°C for 60 min, the absorbance was measured at 585 nm.

[0097] Inhibition (%) = [1-(TT 0 ) / (CC 0 )]×100%

[0098] Where: T is the absorbance value of the sample tube; T 0 is the absorbance value of the sample control tube; C is the absorbance value of the negative control tube; C 0 is the absorbance value of the blank control tube.

[0099] The results are as follows Figure 8 As shown, from Figure 8 It can be seen that when the concentration of proanthocyanidins in the sample increases, the inhibition rate increases with the increase of the proanthocyanidin concentration. When the concentration is the highest, the inhibition rate can reach up to 99.68%. Therefore, the hydrogel has a certain anti-inflammatory effect.

[0100] 6) Cytotoxicity assay:

[0101] Cytocompatibility test Cytotoxicity was evaluated by CCK-8 test. Briefly, the hydrogels (Examples 4-7) were sterilized under UV light for 30 minutes, and then the extract (10 mg / mL) was obtained by soaking the sterile hydrogels in DMEM medium. Hacat cells were seeded into 96-well plates at an initial density of 10,000 cells / well, wherein DMEM was supplemented with 10% (v / v) fetal bovine serum (FBS) and 1% (v / v) penicillin-streptomycin. The cells were then placed at 37°C and 5% CO 2 incubator under 4% CO 2 conditions for 24 hours.

[0102] After that, the above solution was added to a 96-well plate and incubated for 24 hours. Wells without any sample were set as control groups. After removing the supernatant and cell washing steps, the solution was prepared in the plate by mixing CCK-8 and DMEM in a ratio of 1:10 and incubated at 37°C for another 2 hours. The absorbance was measured at 450nm using a microplate reader. The relative cell viability was calculated using the following formula:

[0103]

[0104] Among them A T is the absorbance of the aqueous gel sample, AB is the absorbance of the blank, A C is the absorbance of the control. The average of three measurements was calculated for each set of samples.

[0105] The results are as follows Fig. 9 As shown, from Fig. 9 It can be seen that all four samples have no biological toxicity.

[0106] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A method for preparing an antibacterial and antioxidant hydrogel, characterized in that: The steps include: S1: preparing a carboxymethyl chitosan solution and an acrylamide solution respectively, mixing them evenly, and then adding an acryloyloxyethyl trimethyl ammonium chloride solution to obtain a mixed solution; S2: adding a crosslinking agent, an initiator and a catalyst to the mixed solution obtained in step S1, mixing well and then ultrasonically degassing to obtain a hydrogel precursor; S3: Swelling the hydrogel precursor obtained in step S2 with a polyphenol compound to obtain the hydrogel.

2. The method for preparing an antibacterial and antioxidant hydrogel according to claim 1, characterized in that: The concentration of the carboxymethyl chitosan solution is 0.5-2wt%; the mass concentration of the acrylamide solution is 0.1-0.5g / mL; and the concentration of the acryloyloxyethyl trimethyl ammonium chloride solution is 0.5-2wt%.

3. The method for preparing an antibacterial and antioxidant hydrogel according to claim 1, characterized in that: The volume ratio of the carboxymethyl chitosan solution to the acrylamide solution is 1:1-1:3, and the volume ratio of the acryloyloxyethyl trimethyl ammonium chloride solution to the acrylamide solution is 0.2:1-0.25:

1.

4. The method for preparing an antibacterial and antioxidant hydrogel according to claim 1, characterized in that: The cross-linking agent is N,N-methylenebisacrylamide, the initiator is ammonium persulfate, and the catalyst is N,N,N',N'-tetramethylethylenediamine.

5. The method for preparing an antibacterial and antioxidant hydrogel according to claim 1, characterized in that: The mass ratio of the crosslinking agent to acrylamide in the acrylamide solution is 0.001:1-0.002:1, the mass ratio of the initiator to acrylamide in the acrylamide solution is 1:10-1.5:10, and the volume ratio of the catalyst to the mixed solution is 0.5:1000-1:1000.

6. The method for preparing an antibacterial and antioxidant hydrogel according to claim 1, characterized in that: The polyphenolic compound is one or more of tannic acid, quercetin, curcumin and proanthocyanidin, and the concentration of the polyphenolic compound is 0.1-0.4wt%.

7. The method for preparing an antibacterial and antioxidant hydrogel according to claim 1, characterized in that: The dosage ratio of the polyphenol compound to the hydrogel precursor is 100-500 μL:0.1 g.

8. The method for preparing an antibacterial and antioxidant hydrogel according to claim 1, characterized in that: The mixing described in step S1 is performed in an ice bath.

9. An antibacterial and antioxidant hydrogel, characterized in that: The method is adopted as claimed in any one of claims 1 to 8.

10. Use of the antibacterial and antioxidant hydrogel according to claim 9 as a dressing.

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