An antibacterial medical hydrogel and a preparation method and application thereof

Abstract

The present application relates to the field of hydrogel, in particular to an antibacterial medical hydrogel and its preparation method and application. The raw materials of the hydrogel include tri-lysine, functional polypeptide, multi-arm-polyethylene glycol derivative and polyethyleneimine, wherein the amino acid sequence of the functional polypeptide includes RGD peptide and the polypeptide described in SEQ ID NO. 1. The hydrogel has the effects of antibiosis and promoting fibroblasts by adding the functional polypeptide, which is beneficial to the healing of wounds and has a wide application prospect in wound sealing.

Description

Technical Field

[0001] This invention relates to the field of hydrogels, specifically to an antibacterial medical hydrogel, its preparation method, and its application. Background Technology

[0002] Postoperative tissue leakage (such as cerebrospinal fluid leakage, blood leakage, and digestive fluid leakage) is a common complication in clinical surgery. Mild cases may prolong the healing period, while severe cases can lead to infection, organ dysfunction, or even endanger the patient's life. Therefore, developing surgical sealing materials that can rapidly close tissue defects and effectively prevent fluid leakage is of significant clinical importance.

[0003] Currently, widely used surgical sealants in clinical practice mainly include cyanoacrylate adhesives, fibrin adhesives, and polyethylene glycol (PEG)-based hydrogel products. While cyanoacrylate adhesives offer advantages such as rapid gelation and strong adhesion, their polymerization process releases heat, and their degradation product, formaldehyde, has cytotoxic properties and may cause local tissue inflammation, limiting their application in sensitive in vivo sites. Fibrin adhesives exhibit good biocompatibility, but as they are derived from animal blood products, they pose a risk of pathogen transmission. Furthermore, their relatively weak mechanical strength and limited tissue adhesion make them unsuitable for sealing applications in high-tension areas or under pressure conditions within body cavities.

[0004] Polyethylene glycol-based hydrogels have become a research hotspot in the field of surgical sealants due to their excellent biocompatibility, biodegradability, and tunable physicochemical properties. Existing PEG-based surgical sealants typically use multi-armed PEG active esters (such as tetra-armed PEG-succinimide ester) and multi-armed PEG amino groups (such as tetra-armed PEG-amine) to form a hydrogel network through an electrophilic-nucleophilic reaction. However, these traditional PEG hydrogels still have the following technical defects: (1) The simple PEG network lacks bioactive sites and cannot actively promote cell adhesion, proliferation, and tissue regeneration, only playing a physical barrier role; (2) The gelation speed and mechanical strength of some PEG sealants are still difficult to balance, and the adhesion stability in wet or dynamic physiological environments needs to be improved; (3) Most existing products are two-component systems. Although in-situ cross-linking can be achieved through dual-syringe syringes, the microstructure after gelation is relatively dense and lacks a porous network structure that is conducive to cell ingrowth.

[0005] To improve the bioactivity of PEG hydrogels, researchers have attempted to introduce functional peptides (such as short arginine-glycine-aspartic acid peptides containing RGD sequences). RGD sequences are integrin recognition sites widely present in the extracellular matrix, mediating specific adhesion between cells and material surfaces, and promoting cell proliferation and tissue integration. It has been reported that grafting RGD short peptides onto thermosensitive polymers or self-assembling peptides has successfully prepared injectable hydrogels that promote cell adhesion. However, existing RGD-functionalized hydrogels mostly employ physical blending or simple chemical grafting strategies, making it difficult to guarantee the uniformity of RGD peptide distribution and exposure efficiency within the gel network. Furthermore, most systems lack the ability to synergistically regulate the mechanical properties of the gel.

[0006] On the other hand, polyethyleneimine (PEI), a cationic polymer rich in primary amine groups, has been widely used as a gene delivery vector and hydrogel crosslinking agent. PEI's branched structure provides abundant crosslinking sites, significantly enhancing the network density and mechanical strength of hydrogels. However, the introduction of PEI is often accompanied by increased cytotoxicity, and its use in gel systems is relatively limited; there are few reports of PEI being synergistically applied with functional peptides in PEG-based surgical sealants.

[0007] In conclusion, developing a surgical sealing material that combines rapid gelation properties, strong mechanical strength, good biocompatibility, and active tissue repair promotion remains a pressing technical problem to be solved in this field. Summary of the Invention

[0008] To address the current limitations of existing PEG hydrogels, such as insufficient bioactivity, inadequate adhesion, and the difficulty in synergistically optimizing mechanical properties and biological functions, this invention proposes a multi-component surgical sealing gel system based on a nucleophilic-electrophilic crosslinking mechanism. This system innovatively combines RGD functionalized peptides with hyperbranched polyethyleneimine as the nucleophilic component, which is then crosslinked in situ with a multi-arm polyethylene glycol derivative electrophilic component to form a gel network. This aims to simultaneously achieve multiple functions, including rapid sealing, strong adhesion, and active healing promotion, providing a superior sealing material solution for postoperative tissue repair.

[0009] In a first aspect, the present invention provides an antibacterial medical hydrogel, wherein the raw materials of the hydrogel include trilysine, a functional polypeptide, a multi-arm polyethylene glycol derivative and polyethyleneimine, wherein the amino acid sequence of the functional polypeptide includes RGD peptide and the polypeptide described in SEQ ID NO.1.

[0010] Furthermore, the functional polypeptide is linked to the C-terminus of a trilysine residue. Further, the amino acid sequences of the trilysine-functional polypeptide obtained by linking the functional polypeptide to the C-terminus of a trilysine residue are shown in SEQ ID NO. 2-4.

[0011] Furthermore, the mass concentration of the trilysine-functional peptide is 6-10 mg / mL, the mass concentration of polyethyleneimine is 12-20 mg / mL, and the mass concentration of the multi-arm polyethylene glycol derivative is 200-400 mg / mL.

[0012] Further, the molecular weight of the polyethyleneimine is 200-100,000, preferably 200-20,000, more preferably 500-8,000, and particularly preferably 1,800, wherein the molar content of the primary amine group in all amine groups is 10%-90%, preferably 15%-70%, and more preferably 20%-45%; the molecular weight of the multi-arm polyethylene glycol derivative is 500-100,000, preferably 500-50,000, and more preferably 1,000-30,000.

[0013] In a second aspect, the present invention provides a method for preparing the antibacterial medical hydrogel, the method comprising the following steps: dissolving a first component containing nucleophilic functional groups in buffer A with a pH of 7.5-12.5 to obtain solution A; dissolving a second component containing electrophilic functional groups in buffer B with a pH of 3.0-5.0 to obtain solution B; and then mixing solution A and solution B, wherein the first component and the second component undergo a cross-linking reaction to form a hydrogel.

[0014] Further, the first component includes a trilysine-functional polypeptide and polyethyleneimine, preferably PEI-1800 (molecular weight 1800, primary amino content 35%), and the second component includes a multi-arm polyethylene glycol derivative, preferably a 4-arm polyethylene glycol-succinimide glutarate (4-arm-PEG-SG) with a molecular weight of 10000.

[0015] Furthermore, the concentration of trilysine-functional peptide in the first component is 8 mg / mL, the concentration of PEI-1800 is 16 mg / mL, and the concentration of 4-arm-PEG-SG in the second component is 200-400 mg / mL.

[0016] Furthermore, the volume ratio of solution A to solution B is 2:1 to 1:2, preferably 1:1.

[0017] In a third aspect, the present invention provides the application of the aforementioned antibacterial medical hydrogel in any of the following aspects: A1. Applications in the preparation of antibacterial products; A2. Application in the preparation of products that promote wound closure; A3. Applications in the preparation of products that promote wound healing.

[0018] Furthermore, the product also includes additives or excipients acceptable in the pharmaceutical field.

[0019] The beneficial effects of the present invention include, but are not limited to: This invention proposes a multi-component surgical sealing gel system based on a nucleophilic-electrophilic crosslinking mechanism. This system innovatively combines RGD functionalized peptides with hyperbranched polyethyleneimine as the nucleophilic component, and forms a gel network through in-situ crosslinking with a 4-arm-polyethylene glycol-succinimide glutarate electrophilic component. The aim is to simultaneously achieve multiple functions such as rapid sealing, strong adhesion, and active healing promotion, providing a superior sealing material solution for postoperative tissue repair. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is the chemical structural formula of hyperbranched polyethyleneimine (PEI-1800) in the embodiments of the present invention; Figure 2 This is the chemical structural formula of 4-arm-polyethylene glycol-succinimide glutarate (4-arm-PEG-SG) in the embodiments of the present invention; Figure 3 This is an electron microscope image of the hydrogel prepared in group 5 of the present invention; Figure 4 This is a schematic diagram of the swelling rate-time curve results in an embodiment of the present invention. Detailed Implementation

[0021] The present invention is described in detail below with reference to the embodiments, but the present invention is not limited to these embodiments. Unless otherwise specified, the raw materials and catalysts in the embodiments of the present invention are all purchased through commercial channels.

[0022] Example 1: Screening of peptides RGD peptides act like "molecular glue," helping skin cells (such as fibroblasts) adhere to the gel scaffold, accelerating their migration and proliferation to the wound site, thereby promoting re-epithelialization and granulation tissue formation.

[0023] The active fragment of LL-37, KR-12 (12-peptide): KR-12 is the smallest active fragment of LL-37, the only cathelicidin family antimicrobial peptide in the human body, corresponding to amino acid residues 18-29, with the sequence KRIVQRIKDFLR (SEQ ID NO. 1). Compared with the full-length LL-37, KR-12 retains the core function while having significant advantages such as smaller molecular weight, lower synthesis cost, and significantly reduced cytotoxicity.

[0024] The following trilysine-functional peptides were synthesized by Shanghai Jier Biochemical Reagent Co., Ltd. using solid-phase peptide synthesis: KKK RGD KRIVQRIKDFLR (SEQ ID NO. 2); KKK RGD KRIVQRIKDFLR RGD (SEQ ID NO.3); KKK KRIVQRIKDFLR RGD (SEQ ID NO. 4); RGD KRIVQRIKDFLR (SEQ ID NO.5); RGD KRIVQRIKDFLR KKK (SEQ ID NO. 6).

[0025] Example 2: Preparation method of hydrogel Reagents: Nucleophilic component A: The trilysine-functional peptide shown in SEQ ID NO.2 prepared in Example 1; Nucleophilic component B: Hyperbranched polyethyleneimine (PEI-1800) MW 1800, primary amine content 35%, purchased from Aladdin, structural formula as follows Figure 1 As shown; Electrophilic component: 4-arm-PEG-SG (4-arm-PEG-SG), MW 10000, purchased from Aladdin, structural formula as follows Figure 2 As shown; Buffer A: 0.1 M borate buffer, pH 9.5. Preparation method: Weigh 6.18 g boric acid (H3BO3) and dissolve it in about 800 mL of deionized water. Adjust the pH to 9.5 with 0.1 M NaOH solution, bring the volume to 1000 mL, filter through a 0.22 μm filter membrane for sterilization, and store at 4℃ for later use. Buffer B: Dilute hydrochloric acid solution, pH 4.0. Preparation method: Take 9 mL of concentrated hydrochloric acid and dilute it to 1000 mL. Add water to adjust the pH to 4.0 to obtain a dilute hydrochloric acid solution with pH 4.0.

[0026] Experimental steps: Preparation of nucleophilic component mixed solution (solution A): Accurately weigh 5 mg of functional peptide powder and 10 mg of PEI-1800 and dissolve them in 2.5 mL of buffer A (pH 9.5). Vortex or sonicate until completely dissolved, filter through a 0.22 μm filter membrane for sterilization, aliquot, and store at -20°C for later use.

[0027] Preparation of electrophilic component solution (solution B): Accurately weigh 500 mg of 4-arm-PEG-SG, dissolve in 2.5 mL of buffer B (pH 4.0), vortex until completely dissolved, filter sterilize through a 0.22 μm filter membrane, aliquot and store at -20℃ for later use.

[0028] Preliminary gelation test (inverted tube method): Remove solutions A and B from -20℃ and thaw at room temperature. Add 200 μL of solutions A and B to 1.5 mL centrifuge tubes in equal volume ratios. Mix thoroughly by rapid pipetting or vortexing, and record the start time of mixing. Place the centrifuge tubes in a 37℃ incubator and incubate. Tilt the centrifuge tubes every 2-3 seconds to observe the flowability and record the gelation time (the point at which the solution stops flowing). Perform three replicates per group.

[0029] Optimize the ratio and select the appropriate formula: Adjust the concentrations of solutions A and B according to the concentrations in Table 1 to obtain the optimal gelation time.

[0030] Table 1 Concentrations of solutions A and B

[0031] Since the ideal gelation time for medical blocking gels should be within 10 seconds, but a gelation time of less than 3 seconds will result in excessively fast gelation and difficulty in mixing, the concentration of trilysine-functional peptide in solution A is 6-10 mg / mL, the concentration of PEI-1800 is 12-20 mg / mL, and the concentration of (4-arm-PEG-SG) in the solution is 200-400 mg / mL.

[0032] The other trilysine-functional peptides in Example 1 were replaced with the trilysine-functional peptide polypeptide shown in SEQ ID NO.2. The concentration of trilysine-functional peptide in solution A was 8 mg / mL, the concentration of PEI-1800 was 16 mg / mL, and the concentration of 4-arm-PEG-SG was 250 mg / mL. The gelation time was calculated, and the results are shown in Table 2.

[0033] Table 2. Gel formation time of different peptides

[0034] Tables 1 and 2 demonstrate that SEQ ID NOs 2, 3, 4, and 6 have significantly different effects on gelation time.

[0035] Example 3 Quality Control and Characterization Methods (1) The hydrogels prepared in group 5 were examined by electron microscopy, and the results are as follows: Figure 3 As shown, by Figure 3As can be seen, this hydrogel has a typical three-dimensional porous network structure with relatively uniform pore distribution and pore size ranging from tens to hundreds of micrometers. This interconnected porous structure facilitates cell migration, nutrient exchange, and metabolic waste removal, providing a favorable microenvironment for tissue ingrowth and wound healing.

[0036] (2) Tissue adhesion strength test Fresh detached pig skin: taken from the slaughterhouse (refrigerated at 4°C, use within 24 hours), subcutaneous fat removed, cleaned with PBS buffer, and cut into 2 cm × 5 cm strips.

[0037] Universal testing machine: equipped with a 1 kN or 100 N force sensor (selected according to the estimated adhesion force), pneumatic or mechanical clamps (with anti-slip surface).

[0038] Mark the overlapping area at one end (the adhesive end) of the two pieces of pigskin with a waterproof marker: 1 cm × 2 cm (1 cm overlap along the length and 2 cm overlap along the width). Apply approximately 0.2–0.3 mL of freshly mixed gel (enough to cover the overlapping area) to the marked area on one piece of pigskin. Quickly bring the other piece of pigskin together, ensuring the overlapping area is fully aligned, and gently press for 10 seconds (approximately 1–2 N of pressure, which can be controlled using weights or a heavy object). Place the assembled sample in a 37°C incubator and cure for 10 minutes. Avoid moving or vibrating during this time; a 10 g weight (such as a small metal block) can be placed on the sample to maintain contact pressure.

[0039] Clamp both ends of the pigskin into the upper and lower clamps of the testing machine, with a clamping depth of approximately 1 cm, ensuring the pigskin is vertically aligned (avoid tilting to prevent peeling force). The software controls the clamp movement, keeping the sample slightly stretched but not under stress (force close to 0 N). Before testing, spray a small amount of PBS onto the pigskin surface using a spray bottle to keep it moist (but do not allow it to drip).

[0040] Setting parameters: Tensile rate: 10 mm / min; Data acquisition frequency: 10 Hz (10 points per second); Stopping conditions: The force value drops to 50% of the peak force or the displacement reaches 10 mm; Start the test: Record the force-displacement curve until the adhesive layer completely separates. Read the maximum force (F_max, in N) from the software. Calculate the adhesion strength, three repetitions per group. The formula is as follows:

[0041] F max Maximum separation force (N); A: Actual overlapping area (cm²) = length × width.

[0042] The results are shown in Table 3. The results show that the adhesion strength of the hydrogels containing functional peptides prepared in groups 5, 9 and 10 is >4 N / cm², which can be used for wound closure on the skin surface. However, the adhesion strength of groups 11 and 12 is low, and group 12 does not meet the requirements.

[0043] Table 3 Adhesion strength of each gel

[0044] (3) Swelling rate The hydrogels prepared in groups 5, 9, 10, and 12 were lyophilized and placed in weighing bottles. They were weighed on an analytical balance, and W0 (mg) was recorded. If the gel is highly hygroscopic, it should be stored in a desiccator and weighed quickly. The gel was placed in a 50 mL centrifuge tube or glass petri dish, and 30 mL of preheated PBS was added (ensuring complete immersion). The dish was placed in a 37°C water bath and shaken at low speed (50 rpm). The gel was removed at time points of 0.5, 1, 2, 4, 6, 8, 12, and 24 h: It was gently removed with plastic tweezers to avoid damage. After removing surface moisture, it was immediately placed in a pre-weighed aluminum foil dish and weighed, covered to prevent evaporation, and Wt (mg) was recorded. After weighing, it was quickly returned to fresh PBS to continue swelling. When the difference between two consecutive measurements was <5%, it was considered to be in swelling equilibrium, and Weq was recorded. A swelling rate (%) - time (h) curve was plotted. The results are as follows: Figure 4 As shown.

[0045]

[0046] Table 4 Gel swelling rate at different time points

[0047] Figure 4 As shown in Table 4, the swelling rate of the hydrogels in each group increased with time and tended to reach equilibrium within 24 hours. Among them, the swelling rate of group 5 (SEQ ID NO.2) was the lowest (72.31% at 24h), while the swelling rate of group 12 (SEQ ID NO.6) was the highest (81.25% at 24h). This indicates that the shorter the gelation time and the denser the cross-linking, the lower the swelling rate, which further verifies the advantage of SEQ ID NO.2 in constructing low-swelling and highly stable hydrogels.

[0048] (4) Antibacterial test Gram-positive bacteria: Staphylococcus aureus.

[0049] Gram-negative bacteria: Escherichia coli.

[0050] Storage: Prepare glycerol cryovials and store at -80°C. Activate to the 3rd generation before use.

[0051] Blank control group: Culture medium without hydrogel (normal bacterial growth control).

[0052] Experimental group: Hydrogels containing functional peptides prepared in groups 5, 9, 10, and 12.

[0053] Negative control group: Hydrogels prepared from trilysine, hyperbranched polyethyleneimine (PEI-1800), and 4-arm-PEG-SG.

[0054] Preparation of bacterial suspension: Pick a single colony from a fresh plate and inoculate it into 5 mL of LB liquid medium. Incubate overnight at 37°C with shaking at 200 rpm. Take 1 mL of the overnight culture, centrifuge at 4000 rpm for 5 min, discard the supernatant, resuspend the culture in sterile PBS, wash twice, and dilute with PBS to OD. 600 ≈ 0.1 (approximately 10) 8 (CFU / mL), then diluted to 10. 6 CFU / mL.

[0055] Co-culturing: Add 100 μL of the above bacterial suspension to each LB medium containing the gel block, ensuring the gel is completely submerged. A bacterial suspension without gel was provided as a blank control.

[0056] Incubation: Incubate at 37°C with shaking (100 rpm) for 24 h.

[0057] Counting: After the predetermined time, vortex the system vigorously for 1 minute to thoroughly mix the bacteria in contact with the gel surface. Perform a 10-fold serial dilution, and spread 100 μL of each dilution onto TSA plates.

[0058] Culture: After incubation at 37°C for 18-24 hours, count the colony forming units (CFU).

[0059] Calculate the sterilization rate: Sterilization rate (%) = [1 - (experimental group CFU / mL / blank control group CFU / mL)] × 100%.

[0060] The results are shown in Table 5. The results indicate that the hydrogel containing functional peptides of the present invention has a good antibacterial effect, which is significantly better than that of the negative control group.

[0061] Table 5. Results of antibacterial rate of hydrogel

[0062] (5) Experiments to promote fibroblast formation Fibroblasts: L929, mouse subcutaneous fibroblasts.

[0063] Experimental Groups: Experimental group: KKK-functional peptide / PEI-1800 / PEG-SG gel; Negative control 1: KKK / PEI-1800 / PEG-SG gel (non-functional peptide); Negative control 2: PEI-1800 / PEG-SG gel; Blank control group: No gel, only culture medium.

[0064] Hydrogels containing functional peptides prepared in groups 5, 9, 10, and 12 were cured at 37°C for 30 minutes. Cell culture medium (DMEM + 10% FBS + 1% antibiotics) was added at a ratio of 0.1-0.2 g gel / mL culture medium, and the mixture was extracted at 37°C for 24 hours. The extract was collected, filtered through a 0.22 μm filter for sterilization, and stored at 4°C for short-term storage and -20°C for long-term storage.

[0065] L929 cells were digested, resuspended, counted, and seeded in 96-well plates at a density of 5 × 10³ cells / well. The cells were then incubated overnight (12-24 hours) at 37°C with 5% CO2 to allow them to adhere.

[0066] Remove the original culture medium and add 100 μL / well gel extraction buffer (experimental group) or control culture medium. Set up 3-5 replicates per group and continue culturing for 1, 3, 5, and 7 days (for different time points). At the detection time point, add 10 μL of CCK-8 reagent to each well and incubate at 37℃ for 2 hours. Measure the OD using a microplate reader. 450 nm (reference wavelength 650nm), calculate cell viability: Cell viability (%) = (OD experimental group - OD blank) / (OD control group - OD blank) × 100%.

[0067] The results are shown in Table 6. The results indicate that the hydrogel containing the functional peptide exhibits good cell compatibility and significantly lower cytotoxicity than the negative controls 1 and 2, making it suitable for wound healing. Group 9 showed the highest cell survival rate, presumably due to the presence of two RGD groups in the peptide SEQ ID NO.3 used in group 9. The inventors unexpectedly discovered that covalently cross-linking PEI with a trilysine-functional peptide within a PEG network significantly reduces the cytotoxicity of free PEI, possibly attributed to the consumption of primary amine groups during the cross-linking reaction.

[0068] Table 6. Results of cell viability experiments

[0069] (6) Animal models Experimental animals: SD rats, male, weighing 200-250g, fasted for 12 hours before surgery (water allowed).

[0070] Anesthesia is administered via isoflurane inhalation or intraperitoneal injection of sodium pentobarbital (40-50 mg / kg). The back is shaved (approximately 5 cm × 5 cm, centered on the spine). The area is disinfected with povidone-iodine, and povidone-iodine swabs are used to disinfect from the center outwards (approximately 8 cm × 8 cm). The area is then deiodized with 75% ethanol. A sterile drape is placed to expose the surgical area. Sterile drapes are placed on both sides of the midline of the back. A full-thickness skin incision (2-3 cm in length, reaching the fascia layer) is made using a sterile scalpel. Sterile gauze is applied for hemostasis. Premixed solutions A (groups 5, 9, 10, and 12) and B (using a dual-syringe syringe with a static mixing tip) are evenly applied to the incision surface to a thickness of approximately 1-2 mm (enough to completely cover the incision). The gel is allowed to fully harden for 5-10 seconds. The area is then covered with sterile gauze and secured with an elastic bandage.

[0071] Table 7 Comparison of postoperative wound healing rates in rats of different groups (%, Mean±SD, n=6)

[0072] All rats recovered well post-surgery, with no deaths or serious infections. On post-surgery day 3, the blank control group (sutured but without adhesive) showed significant redness and swelling with a small amount of exudate at the incision site, while the experimental groups (groups 5, 9, 10, and 12) had dry incisions, mild redness and swelling, and complete gel coverage that adhered tightly to the wound edges. On post-surgery day 7, the gel in the experimental group had partially degraded, and the wound was covered with new epithelial tissue, with clear and neatly aligned incision healing lines; the blank control group and the negative control group (without functional peptide gel) still showed scabs, indicating delayed healing. On post-surgery day 14, the incisions in the experimental group were completely healed, with smooth new skin and almost no scar hyperplasia; the blank control group had wider healing lines and more noticeable scars.

[0073] Wound healing rate (%) = (Initial area - Current area) / Initial area × 100% The results are shown in Table 7. The healing rates of the experimental groups (groups 5, 9, 10, and 12) with the introduction of functional peptides were significantly higher than those of the negative control group and the blank control group at all time points, indicating that the hydrogel of the present invention can effectively accelerate the closure of full-thickness skin defects.

[0074] Animal in vivo experiments have confirmed that the antibacterial medical hydrogel provided by this invention has excellent tissue compatibility, can effectively seal wounds, resist infection, reduce early inflammatory response, and significantly promote wound re-epithelialization and orderly collagen deposition through the bioactive effects of functional peptides, thus having clear application value in accelerating postoperative wound healing.

[0075] Considering factors such as gelation time, adhesion strength, and wound healing, the hydrogels prepared in groups 5 and 9 showed the best results.

[0076] The above description is merely an embodiment of the present invention, and the scope of protection of the present invention is not limited to these specific embodiments, but is determined by the claims of the present invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the technical concept and principle of the present invention should be included within the scope of protection of the present invention.

Claims

1. An antibacterial medical hydrogel, characterized in that, The hydrogel raw materials include trilysine, functional peptides, multi-arm polyethylene glycol derivatives, and polyethyleneimine, wherein the amino acid sequence of the functional peptides includes RGD peptides and the peptide described in SEQ ID NO.

1.

2. The antibacterial medical hydrogel according to claim 1, characterized in that, The functional polypeptide is linked to the carbon or nitrogen terminus of trilysine to obtain a trilysine-functional polypeptide.

3. The antibacterial medical hydrogel according to claim 2, characterized in that, The mass concentrations of trilysine-functional peptides are 6-10 mg / mL, polyethyleneimine is 12-20 mg / mL, and multi-arm polyethylene glycol derivatives are 200-400 mg / mL.

4. The antibacterial medical hydrogel according to claim 1, characterized in that, The molecular weight of the polyethyleneimine is 200-100,000.

5. A method for preparing the antibacterial medical hydrogel according to any one of claims 1-4, characterized in that, The method includes the following steps: dissolving a first component containing nucleophilic functional groups in buffer A with a pH of 7.5-12.5 to obtain solution A; dissolving a second component containing electrophilic functional groups in buffer B with a pH of 3.0-5.0 to obtain solution B; and then mixing solution A and solution B, whereby the first and second components undergo a cross-linking reaction to form a hydrogel.

6. The method according to claim 5, characterized in that, The first component includes a trilysine-functional peptide and polyethyleneimine, wherein the polyethyleneimine is PEI with a molecular weight of 1800. The second component includes a multi-arm polyethylene glycol derivative, wherein the multi-arm polyethylene glycol derivative is a 4-arm polyethylene glycol-succinimide glutarate with a molecular weight of 10000.

7. The method according to claim 6, characterized in that, The first component contains 8 mg / mL of trilysine-functional peptide and 16 mg / mL of PEI, while the second component contains 200-400 mg / mL of 4-arm polyethylene glycol-succinimide glutarate.

8. The method according to claim 5, characterized in that, The volume ratio of solution A to solution B is 2:1 to 1:

2.

9. The application of the antibacterial medical hydrogel as described in any one of claims 1-4 in any of the following aspects: A1. Applications in the preparation of antibacterial products; A2. Application in the preparation of medical sealants for sealing tissue defects or preventing leakage; A3. Applications in the preparation of products that promote wound healing.

10. The application according to claim 9, characterized in that, The product also includes additives or excipients acceptable in the pharmaceutical field.

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