Antibacterial hydrogel and its preparation method and application

Abstract

The invention discloses an antibacterial hydrogel and a preparation method and application thereof, which belongs to the field of medical device technology, and includes the following raw materials: chitosan, N,N-bis(2-hydroxyethyl)glycine, antimicrobial peptides and D-glucuronolactone. The preparation method thereof comprises the following steps: adding an activated solution of N,N-bis(2-hydroxyethyl)glycine to a chitosan solution, dialysis after stirring, and freeze drying to obtain N,N-bis(2-hydroxyethyl)glycine-g-chitosan; adding antimicrobial peptides and D-glucuronolactone aqueous solution to the aqueous solution of N,N-bis(2-hydroxyethyl)glycine-g-chitosan in sequence, mixing evenly and standing to form a gel state to obtain an antibacterial hydrogel. The antibacterial hydrogel obtained by the invention has excellent self-healing properties and good biocompatibility, and has good application prospects in the preparation of medical antibacterial and wound repair materials.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and in particular relates to an antibacterial hydrogel and a preparation method and application thereof. Background Art

[0002] Wound healing is a complex physiological process. Chronic wounds caused by severe bacterial infection of the wound often cannot be completed smoothly and require long-term treatment, which brings great physical and psychological pain to patients. Wound infection is a thorny global problem that may lead to life-threatening complications, induce chronic inflammation, and lead to impaired wound repair. The treatment of wound repair is crucial to shorten recovery time, reduce patient pain, and prevent complications. Currently, antibiotics are still the first choice for clinical prevention and treatment of wound infection. However, the abuse of antibiotics can easily lead to drug resistance in pathogens and increase their tolerance to drugs, ultimately leading to the emergence of "super bacteria". Therefore, it is very necessary to find new antimicrobial agents and polymer materials to replace antibiotics.

[0003] With the deepening and refinement of clinical needs, wound dressings have gradually changed from a single wound covering and isolating function to a multifunctional effect. Among them, hydrogels have become the most competitive candidate materials for wound dressings, especially natural polysaccharide-based antibacterial hydrogels with self-healing properties, which are expected to be more widely used in clinical practice. However, natural polysaccharide chitin and chitosan-based self-healing hydrogels often use toxic cross-linking agents such as glutaraldehyde in the preparation process. These cross-linking agents have certain cytotoxicity, which limits their application in biomedical materials.

[0004] Therefore, how to provide a non-toxic antibacterial hydrogel with a wide range of applications is a technical problem that those skilled in the art urgently need to solve. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides an antibacterial hydrogel and a preparation method and application thereof.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] An antibacterial hydrogel comprises the following raw materials in parts by weight:

[0008] 1-4 parts of chitosan, 1.5-3.5 parts of N,N-bis(2-hydroxyethyl)glycine, 0.2-0.6 parts of antimicrobial peptide and 0.04-0.06 parts of D-glucuronolactone.

[0009] Preferably, the following raw materials are included in parts by weight:

[0010] 2 parts of chitosan, 2.5 parts of N,N-bis(2-hydroxyethyl)glycine, 0.4 parts of antimicrobial peptide and 0.05 parts of D-glucuronolactone.

[0011] Preferably, the deacetylation degree of the chitosan is ≥95%.

[0012] Preferably, the amino acid sequence of the antimicrobial peptide is KVLRVRKLIRIG.

[0013] A method for preparing an antibacterial hydrogel comprises the following steps:

[0014] The activated solution of N,N-bis(2-hydroxyethyl)glycine is added to the chitosan solution, and the solution is dialyzed and freeze-dried after stirring to obtain N,N-bis(2-hydroxyethyl)glycine-g-chitosan;

[0015] The antimicrobial peptide and the D-glucuronolactone aqueous solution are sequentially added to the aqueous solution of N,N-bis(2-hydroxyethyl)glycine-g-chitosan, and the mixture is uniformly mixed and allowed to stand until the mixture becomes a gel state, thereby obtaining an antimicrobial hydrogel.

[0016] Beneficial effects: The present invention firstly enhances the water solubility of chitosan, and avoids using acidic solvents to dissolve chitosan in subsequent processes, thereby avoiding the irritation of the hydrogel to wound tissues during application as a medical product; secondly, the introduction of N,N-bis(2-hydroxyethyl)glycine improves the antibacterial activity of chitosan and exerts a synergistic antibacterial effect with antimicrobial peptides; finally, N,N-bis(2-hydroxyethyl)glycine-g-chitosan contains more terminal hydroxyl groups, and in the process of encapsulating the antimicrobial peptides, it acts as a connector through hydrogen bonding, thereby increasing the stability of the antimicrobial peptides, improving the bioavailability, and exerting a lasting antibacterial effect.

[0017] Preferably, the N,N-bis(2-hydroxyethyl)glycine activation solution is obtained by dissolving N,N-bis(2-hydroxyethyl)glycine in a 95% ethanol solution, adding an activator and stirring evenly, and the concentration of N,N-bis(2-hydroxyethyl)glycine is 0.4-0.8 mol / L.

[0018] Preferably, the activator comprises 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide, and the molar ratio of the N,N-bis(2-hydroxyethyl)glycine, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide is 1:2:3.

[0019] Preferably, the chitosan solution is obtained by dissolving chitosan in an acetic acid aqueous solution, wherein the mass fraction of acetic acid in the acetic acid aqueous solution is 0.5%-1.5%, and the mass fraction of chitosan is 1%-4%;

[0020] The volume of the 95% ethanol solution is 20% to 30% of the volume of the acetic acid aqueous solution.

[0021] Preferably, the mass fraction of the N,N-bis(2-hydroxyethyl)glycine-g-chitosan aqueous solution is 1% to 3%, and the pH is 5;

[0022] The mass fraction of the D-glucuronolactone aqueous solution is 0.5% to 1.5%.

[0023] Beneficial effects: The present invention uses safe and non-toxic D-glucuronolactone as a cross-linking agent. Since the aldehyde group in the D-glucuronolactone structure can react with the amino groups in chitosan and antimicrobial peptides to form a dynamic and reversible covalent bond structure (imine structure); at the same time, the carboxyl group in the D-glucuronolactone structure can generate electrostatic effects with the protonated amino groups in chitosan and antimicrobial peptides, and generate hydrogen bonds with the hydroxyl groups in chitosan and antimicrobial peptides. Therefore, D-glucuronolactone promotes chitosan and antimicrobial peptides to produce a stable three-dimensional network, forming an antibacterial hydrogel with excellent self-healing properties, reducing the possibility of complications caused by rupture in the body tissue as an implant material; this self-healing property of the hydrogel helps to extend the service life of the material and restore and preserve its original properties. At the same time, the antibacterial hydrogel shows excellent advantages in achieving controlled release of antimicrobial peptides, improving treatment efficiency, and reducing side effects.

[0024] The invention discloses an application of an antibacterial hydrogel in the preparation of medical antibacterial and wound repair materials.

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

[0026] The present invention firstly uses activators 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide to activate the carboxyl group of N,N-bis(2-hydroxyethyl)glycine, and introduces N,N-bis(2-hydroxyethyl)glycine into the chitosan molecular chain through an amidation reaction to obtain N,N-bis(2-hydroxyethyl)glycine-g-chitosan. The present invention uses chitosan, a deacetylated product of natural polysaccharide chitin, as a matrix material, and introduces antimicrobial peptides as antimicrobial agents to prepare antibacterial hydrogels, which can give full play to the synergistic antibacterial effects of chitosan and antimicrobial peptides and have a strong antibacterial effect. At the same time, the antibacterial hydrogel obtained by the present invention has excellent self-healing properties and good biocompatibility, and has good application prospects in the field of preparing medical antibacterial and wound repair materials. In addition, the preparation process of the present invention is simple and easy to industrialize. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0028] Figure 1 This is a photo of the appearance of the antibacterial hydrogel obtained in Example 1;

[0029] Figure 2 This is a scanning electron microscope image of the freeze-dried sample obtained after freeze-drying the antibacterial hydrogel obtained in Example 1. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] The embodiment of the present invention provides an antibacterial hydrogel, comprising the following raw materials in parts by weight:

[0033] 1-4 parts of chitosan, 1.5-3.5 parts of N,N-bis(2-hydroxyethyl)glycine, 0.2-0.6 parts of antimicrobial peptide and 0.04-0.06 parts of D-glucuronolactone.

[0034] In a preferred embodiment, the following raw materials are included in parts by weight:

[0035] 2 parts of chitosan, 2.5 parts of N,N-bis(2-hydroxyethyl)glycine, 0.4 parts of antimicrobial peptide and 0.05 parts of D-glucuronolactone.

[0036] In a preferred embodiment, the deacetylation degree of the chitosan is ≥95%.

[0037] In a preferred embodiment, the amino acid sequence of the antimicrobial peptide is KVLRVRKLIRIG.

[0038] The present invention also provides a method for preparing an antibacterial hydrogel, comprising the following steps:

[0039] The activated solution of N,N-bis(2-hydroxyethyl)glycine is added to the chitosan solution, and the solution is dialyzed and freeze-dried after stirring to obtain N,N-bis(2-hydroxyethyl)glycine-g-chitosan;

[0040] The antimicrobial peptide and the D-glucuronolactone aqueous solution are sequentially added to the aqueous solution of N,N-bis(2-hydroxyethyl)glycine-g-chitosan, and the mixture is uniformly mixed and allowed to stand until the mixture becomes a gel state, thereby obtaining an antimicrobial hydrogel.

[0041] In a preferred embodiment, the N,N-bis(2-hydroxyethyl)glycine activation solution is obtained by dissolving N,N-bis(2-hydroxyethyl)glycine in a 95% ethanol solution, adding an activator and stirring evenly, and the concentration of N,N-bis(2-hydroxyethyl)glycine is 0.48-0.74 mol / L.

[0042] In a preferred embodiment, the activator includes 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide, and the molar ratio of the N,N-bis(2-hydroxyethyl)glycine, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide is 1:2:3.

[0043] In a preferred embodiment, the chitosan solution is obtained by dissolving chitosan in an acetic acid aqueous solution, wherein the mass fraction of acetic acid in the acetic acid aqueous solution is 0.5%-1.5%, and the mass fraction of chitosan is 1%-4%;

[0044] The volume of the 95% ethanol solution is 20% to 30% of the volume of the acetic acid aqueous solution.

[0045] In a preferred embodiment, the mass fraction of the N,N-bis(2-hydroxyethyl)glycine-g-chitosan aqueous solution is 1% to 3%, and the pH is 5;

[0046] The mass fraction of the D-glucuronolactone aqueous solution is 0.5% to 1.5%.

[0047] The embodiment of the present invention also provides an application of an antibacterial hydrogel in the preparation of medical antibacterial and wound repair materials.

[0048] Unless otherwise specified, the raw materials in the examples of the present invention were purchased from commercial sources;

[0049] Among them, the amino acid sequence of the antimicrobial peptide in the embodiment of the present invention is KVLRVRKLIRIG.

[0050] The room temperature or normal temperature in the embodiments of the present invention refers to 25±3°C.

[0051] Example 1

[0052] A method for preparing an antibacterial hydrogel comprises the following steps:

[0053] (1) Add 2 g of chitosan (deacetylation degree ≥ 95%) to 98 g (97 mL) of acetic acid aqueous solution (acetic acid mass fraction 1%) and stir to dissolve to obtain a chitosan solution; dissolve 2.5 g (0.015 mol) of N,N-bis(2-hydroxyethyl)glycine in 95% ethanol (24 mL), add 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (5.75 g, 0.03 mol) and N-hydroxysuccinimide (5.18 g, 0.045 mol), and stir at room temperature for 5 h to obtain an activated solution of N,N-bis(2-hydroxyethyl)glycine.

[0054] (2) The activated solution of N,N-bis(2-hydroxyethyl)glycine obtained was added to the chitosan solution, stirred at room temperature for 8 h, dialyzed against distilled water, and freeze-dried to obtain N,N-bis(2-hydroxyethyl)glycine-g-chitosan.

[0055] (3) The obtained N,N-bis(2-hydroxyethyl)glycine-g-chitosan was added to distilled water to prepare a 2% (mass fraction) N,N-bis(2-hydroxyethyl)glycine-g-chitosan aqueous solution. After adjusting the pH to 5, antimicrobial peptide (0.4 g) was added and mixed. Subsequently, 5 g of D-glucuronolactone aqueous solution (mass fraction 1%) was added and mixed. The mixture was allowed to stand until a gel state was reached, thereby obtaining an antibacterial hydrogel.

[0056] Figure 1 This is a photo of the appearance of the antibacterial hydrogel obtained in Example 1. Figure 2 This is a scanning electron microscope image of the freeze-dried sample obtained after freeze-drying the antibacterial hydrogel obtained in Example 1.

[0057] from Figure 1 It can be seen that the antibacterial hydrogel is almost transparent; after the hydrogel is freeze-dried, scanning electron microscopy observation shows that Figure 2 As shown, it can be seen that the freeze-dried antibacterial hydrogel presents a porous layered structure with good permeability and a large absorption capacity for liquids, providing a moist microenvironment for wound tissues and facilitating wound repair.

[0058] Example 2

[0059] A method for preparing an antibacterial hydrogel comprises the following steps:

[0060] (1) Add 1 g of chitosan (deacetylation degree ≥ 95%) to 99 g (99 mL) of acetic acid aqueous solution (acetic acid mass fraction 0.5%) and stir to dissolve to obtain a chitosan solution; dissolve 1.5 g (0.0092 mol) of N,N-bis(2-hydroxyethyl)glycine in 95% ethanol (19.8 mL), add 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (3.53 g, 0.0184 mol) and N-hydroxysuccinimide (3.18 g, 0.0276 mol), and stir at room temperature for 5 h to obtain an activated solution of N,N-bis(2-hydroxyethyl)glycine.

[0061] (2) The activated solution of N,N-bis(2-hydroxyethyl)glycine obtained was added to the chitosan solution, stirred at room temperature for 8 h, dialyzed against distilled water, and freeze-dried to obtain N,N-bis(2-hydroxyethyl)glycine-g-chitosan.

[0062] (3) The obtained N,N-bis(2-hydroxyethyl)glycine-g-chitosan was added to distilled water to prepare a 1% (mass fraction) N,N-bis(2-hydroxyethyl)glycine-g-chitosan aqueous solution. After adjusting the pH to 5, antimicrobial peptide (0.2 g) was added and mixed. Subsequently, 8 g of D-glucuronolactone aqueous solution (mass fraction 0.5%) was added and mixed. The mixture was allowed to stand until a gel state was reached, thereby obtaining an antibacterial hydrogel.

[0063] Example 3

[0064] A method for preparing an antibacterial hydrogel comprises the following steps:

[0065] (1) Add 4 g of chitosan (deacetylation degree ≥ 95%) to 96 g (95 mL) of acetic acid aqueous solution (acetic acid mass fraction 1%) and stir to dissolve to obtain a chitosan solution; dissolve 3.5 g (0.021 mol) of N,N-bis(2-hydroxyethyl)glycine in 95% ethanol (28.5 mL), add 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (8.05 g, 0.042 mol) and N-hydroxysuccinimide (7.25 g, 0.063 mol), and stir at room temperature for 5 h to obtain an activated solution of N,N-bis(2-hydroxyethyl)glycine.

[0066] (2) The activated solution of N,N-bis(2-hydroxyethyl)glycine obtained was added to the chitosan solution, stirred at room temperature for 8 h, dialyzed against distilled water, and freeze-dried to obtain N,N-bis(2-hydroxyethyl)glycine-g-chitosan.

[0067] (3) The obtained N,N-bis(2-hydroxyethyl)glycine-g-chitosan was added to distilled water to prepare a 3% (mass fraction) N,N-bis(2-hydroxyethyl)glycine-g-chitosan aqueous solution. After adjusting the pH to 5, antimicrobial peptide (0.6 g) was added and mixed. Subsequently, 4 g of D-glucuronolactone aqueous solution (mass fraction 1.5%) was added and mixed. The mixture was allowed to stand until a gel state was reached, thereby obtaining an antibacterial hydrogel.

[0068] Comparative Example 1

[0069] A method for preparing an antibacterial hydrogel, which differs from Example 1 only in that the D-glucuronolactone in step (2) is replaced by an equal amount of glutaraldehyde.

[0070] The remaining process steps and parameters are the same as those in Example 1.

[0071] Comparative Example 2

[0072] A method for preparing an antibacterial hydrogel, which differs from Example 1 only in that the N,N-bis(2-hydroxyethyl)glycine in step (2) is replaced by N-tri(hydroxymethyl)methylglycine.

[0073] The remaining process steps and parameters are the same as those in Example 1.

[0074] Comparative Example 3

[0075] A method for preparing an antibacterial hydrogel, which differs from Example 1 only in that the step-by-step method in Example 1 is replaced by a material direct blending method, specifically comprising the following steps:

[0076] 2 g of chitosan (95% deacetylation degree) was added to 98 g of distilled water to obtain a chitosan solution with a mass fraction of 2%. 2.5 g of N, N-bis(2-hydroxyethyl)glycine was added to the chitosan solution, and the pH was adjusted to 5 before adding antimicrobial peptide (0.4 g) and mixing. Subsequently, 5 g of D-glucuronolactone aqueous solution (1% mass fraction) was added, mixed, and allowed to stand until a gel state was reached to obtain an antibacterial hydrogel.

[0077] Effect Example 1

[0078] The self-healing effect test of the hydrogels prepared in Examples 1 to 3 and Comparative Examples 1 to 3 was conducted, specifically comprising the following steps:

[0079] The hydrogel was cut into two parts with a scalpel, and the two parts of the hydrogel were arranged along the cut. A slight external force was applied at room temperature to make the hydrogel cuts completely contact. After 5 hours, the tensile strength of the sample was measured using a universal mechanical testing machine. The sample was stretched at a constant strain rate of 1 mm / min until it was completely stretched to failure. Each test was repeated 3 times, and the average value was taken. The self-healing efficiency of the hydrogel was calculated according to formula (1). The results are shown in Table 1.

[0080] (1)

[0081] Table 1 Self-healing efficiency of hydrogel

[0082]

[0083] The self-healing efficiency reflects the self-healing and repair performance of the material. The larger the value, the stronger the self-healing performance of the material. As can be seen from Table 1, Examples 1 to 3 give the hydrogel good self-healing performance because the dynamic covalent bonds / non-covalent bonds (Schiff base bonds, electrostatic effects, multiple hydrogen bonds) in the hydrogel are reversible. However, in Comparative Examples 1 to 3, the self-healing efficiency of the hydrogel is significantly reduced and the self-healing performance is weakened due to the replacement of the starting materials or the change of the preparation process.

[0084] Effect Example 2

[0085] Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were used to evaluate the antibacterial effect of the test samples, which specifically included the following steps:

[0086] Take the test bacteria in the logarithmic growth phase and dilute them to 1.0×10 6 CFU / mL, set aside. Take 1 mL of sample solution (0.5 mg / mL) and add it to a sterilized EP (eppendorf) tube; add 1 mL of E. coli or S. aureus bacterial suspension (1.0×10 6 CFU / mL), and cultured at 37℃ with shaking (100 r / min) for 18h. Take a certain amount of bacterial culture solution from the above EP tube, dilute the bacterial solution to an appropriate concentration with PBS buffer by ten-fold dilution method, take 100 μL of the diluted bacterial suspension and drop it into the agar culture dish, spread it evenly with a coating rod, and culture it at 37℃ for 24h, and record the number of colonies on the culture dish. Set up a blank positive control group (using distilled water instead of sample solution) and an antibiotic positive control group (gentamicin sulfate, 0.1 mg / mL) respectively. Calculate the antibacterial rate of the sample according to formula (2), and the results are shown in Table 2.

[0087] (2)

[0088] Among them, Nb and Ns are the bacterial colony counts in the blank positive control group and the sample group, respectively.

[0089] Table 2 Antibacterial properties of samples

[0090]

[0091] Hydrogels with antibacterial properties can effectively reduce wound infection and accelerate wound healing. The antibacterial rate reflects the antibacterial properties of a substance. The larger the value, the stronger the antibacterial effect. As can be seen from Table 2, chitosan (deacetylation degree ³95%) has a certain antibacterial effect on the tested bacteria, but the antibacterial ability is low; compared with the raw material chitosan, N, N-bis (2-hydroxyethyl) glycine-g-chitosan has a significantly enhanced antibacterial effect on the two test bacteria, indicating that the chemical modification of chitosan by N, N-bis (2-hydroxyethyl) glycine improves the antibacterial ability of chitosan. The antibacterial peptide obtained by the present invention exhibits a strong antibacterial effect, similar to gentamicin sulfate. Compared with each single-component sample, although the effective concentration of each component in Examples 1 to 3 is reduced, the hydrogel as a whole still exhibits a strong antibacterial ability, showing a synergistic antibacterial effect between the components. However, due to the replacement of the starting raw materials or the change of the preparation process, the antibacterial rate of the hydrogel in Comparative Examples 1 to 3 is significantly reduced, and the antibacterial ability is weakened.

[0092] Effect Example 3

[0093] The antibacterial hydrogels prepared in Example 1 and Comparative Example 1 were used as test samples to conduct biocompatibility tests:

[0094] A certain amount of freeze-dried samples of hydrogel were taken, sterilized by ultraviolet irradiation for 2 hours, and then sterilized with sterile distilled water to prepare hydrogel sample solutions with different gradient concentrations (0.5, 1.0 and 2.0 mg / mL). Then, equal volumes of complete culture medium were added to the solutions and incubated at 37°C for 24 hours. The hydrogel extract was stored in a refrigerator at 4°C for cytotoxicity test.

[0095] Take HaCaT cells in the logarithmic growth phase, count them and adjust the cell concentration to 5×10 4 / mL, 100μL per well was inoculated on a 96-well culture plate, cultured in a 37℃, 5% CO2 incubator for 24 h, the culture medium was aspirated and discarded, DMEM culture medium or culture medium containing hydrogel extract (100μL / well) was added, and culture was continued for 24 h and 48 h, respectively. After the culture was completed, the culture medium was discarded, new culture medium was added, 10μL of CCK-8 was added to each well, a blank control well was set, and the reaction was carried out in the dark at 37℃ for 2 h. The optical density (OD) value of each well was read at 450nm with a microplate reader to calculate the cell viability.

[0096] The CCK-8 method was used to determine the biocompatibility of the hydrogel extract to HaCaT cells. The test results showed that after 24 hours of co-culture, the extract of the antibacterial hydrogel sample obtained in Example 1 at different concentrations (0.5, 1.0 and 2.0 mg / mL) promoted the growth of cells, and the cell viabilities were 101.35±2.44%, 105.31±3.08% and 104.23±2.73%, respectively, all exceeding 100%; the extract of the antibacterial hydrogel sample obtained in Comparative Example 1 at different concentrations had a toxic effect on the growth of cells, and the cell viabilities were 74.15±2.14%, 71.62±3.05% and 64.58±2.72%, respectively, all below 75%; after 48 hours of co-culture, the extract of the antibacterial hydrogel sample obtained in Comparative Example 1 at different gradient concentrations (0.5, 1.0 and 2.0 The cell viability of the antibacterial hydrogel samples obtained in Example 1 (mg / mL) was reduced (96.36±2.56%, 101.13±2.25% and 98.27±3.18%, respectively), but all were greater than 96%; while the cell viability of the antibacterial hydrogel samples obtained in Comparative Example 1 with different concentrations was 49.81±1.87%, 47.47±2.16% and 42.86±3.24%, respectively, all lower than 50%. These results show that the antibacterial hydrogel obtained in Example 1 has no cytotoxicity and has good biocompatibility for HaCaT cells.

[0097] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An antibacterial hydrogel, characterized in that: The invention comprises the following raw materials in parts by weight: 1-4 parts of chitosan, 1.5-3.5 parts of N,N-bis(2-hydroxyethyl)glycine, 0.2-0.6 parts of antimicrobial peptide and 0.04-0.06 parts of D-glucuronolactone; The amino acid sequence of the antimicrobial peptide is KVLRVRKLIRIG; The preparation method of the antibacterial hydrogel comprises the following steps: The activated solution of N,N-bis(2-hydroxyethyl)glycine is added to the chitosan solution, and the solution is dialyzed and freeze-dried after stirring to obtain N,N-bis(2-hydroxyethyl)glycine-g-chitosan; Adding antimicrobial peptide and D-glucuronolactone aqueous solution to an aqueous solution of N,N-bis(2-hydroxyethyl)glycine-g-chitosan in sequence, mixing evenly and letting stand to form a gel state, thereby obtaining an antimicrobial hydrogel; The N,N-bis(2-hydroxyethyl)glycine activation solution is prepared by dissolving N,N-bis(2-hydroxyethyl)glycine in a 95% ethanol solution, adding an activator and stirring evenly, wherein the concentration of N,N-bis(2-hydroxyethyl)glycine is 0.4-0.8 mol / L; The activator includes 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide, and the molar ratio of the N,N-bis(2-hydroxyethyl)glycine, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide is 1:2:

3.

2. The antibacterial hydrogel according to claim 1, characterized in that: The invention comprises the following raw materials in parts by weight: 2 parts of chitosan, 2.5 parts of N,N-bis(2-hydroxyethyl)glycine, 0.4 parts of antimicrobial peptide and 0.05 parts of D-glucuronolactone.

3. The antibacterial hydrogel according to claim 1, characterized in that: The deacetylation degree of the chitosan is 95%.

4. A method for preparing an antibacterial hydrogel according to any one of claims 1 to 3, characterized in that: The following steps are involved: The activated solution of N,N-bis(2-hydroxyethyl)glycine is added to the chitosan solution, and the solution is dialyzed and freeze-dried after stirring to obtain N,N-bis(2-hydroxyethyl)glycine-g-chitosan; Adding antimicrobial peptide and D-glucuronolactone aqueous solution to an aqueous solution of N,N-bis(2-hydroxyethyl)glycine-g-chitosan in sequence, mixing evenly and letting stand to form a gel state, thereby obtaining an antimicrobial hydrogel; The N,N-bis(2-hydroxyethyl)glycine activation solution is prepared by dissolving N,N-bis(2-hydroxyethyl)glycine in a 95% ethanol solution, adding an activator and stirring evenly, wherein the concentration of N,N-bis(2-hydroxyethyl)glycine is 0.4-0.8 mol / L; The activator includes 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide, and the molar ratio of the N,N-bis(2-hydroxyethyl)glycine, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide is 1:2:

3.

5. The method for preparing an antibacterial hydrogel according to claim 4, characterized in that: The chitosan solution is obtained by dissolving chitosan in an acetic acid aqueous solution, and the mass fraction of the chitosan is 1% to 4%.

6. The method for preparing an antibacterial hydrogel according to claim 5, characterized in that: The volume of the 95% ethanol solution is 20% to 30% of the volume of the acetic acid aqueous solution.

7. The method for preparing an antibacterial hydrogel according to claim 4, characterized in that: The mass fraction of the aqueous solution of N,N-bis(2-hydroxyethyl)glycine-g-chitosan is 1% to 3%, and the pH is 5; The mass fraction of the D-glucuronolactone aqueous solution is 0.5% to 1.5%.

8. Use of the antibacterial hydrogel according to any one of claims 1 to 3 in the preparation of medical antibacterial and wound repair materials.

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