Cartilage repair hydrogel material and preparation method thereof

Abstract

The invention discloses a cartilage repair hydrogel material and a preparation method thereof, and relates to the technical field of biomedical materials. The invention proposes that a cartilage repair hydrogel material is obtained by adding a water-soluble derivative of vitamin E, D-α-tocopheryl polyethylene glycol 1000 succinate, 2,4-toluene diisocyanate-modified T-ZIF-8, and SIKVAV peptide-modified Mg-MOF to a mixed solution obtained by compounding silk fibroin peptide, oxidized chondroitin sulfate, and 3-aminophenylboronic acid, and cross-linking the mixture under ultraviolet light. The hydrogel material prepared by the invention has a three-dimensional complex cross-linked structure and strong mechanical properties and stability. The components act synergistically to create adhesion groups and hydrophilic groups on the surface of the hydrogel material, thereby increasing the binding opportunity between bone cells and the surface of the hydrogel material, promoting the adhesion and proliferation of bone cells, reducing the rejection reaction of tissues to metal materials, lowering the inflammatory reaction, and promoting collagen secretion and cartilage regeneration.

Description

Technical Field

[0001] The present invention belongs to the technical field of biomedical materials, and specifically relates to a cartilage repair hydrogel material and a preparation method thereof. Background Art

[0002] Osteoarthritis is a degenerative joint disease and a major cause of chronic pain and mobility problems in the elderly. It begins with subtle, asymptomatic micro-injuries and inflammation. Patients in the middle and late stages of osteoarthritis often experience severe joint pain, instability, and dysfunction, with significantly impaired quality of life. Cartilage defects are the most serious stage of osteoarthritis, with irreversible damage to the cartilage and lesions in the subchondral bone, mainly caused by trauma, aging, and osteoarthritis. Because the subchondral bone cannot be penetrated, the stem cell population and bone marrow blood supply cannot be obtained, resulting in limited intrinsic repair capacity of the cartilage defect site. Conventional clinical treatments include microfracture surgery, autologous chondrocyte implantation, and matrix-induced autologous chondrocyte implantation. However, the implementation of these strategies is inherently complex and can lead to damage to normal cartilage or subchondral bone, accompanied by graft degeneration and the adverse production of abnormal fibrocartilage. Without effective clinical treatment, osteochondral defects will gradually lead to joint pain, degenerative osteoarthritis, and even ultimately joint destruction. Therefore, an effective cartilage repair method is needed.

[0003] As a hydrophilic three-dimensional network structure, hydrogel is a good candidate material for cartilage repair and a research hotspot for the treatment of cartilage damage. However, the current existing technologies mainly have the problems of weak mechanical properties of hydrogels, poor cell affinity and weak bone regeneration ability. Summary of the Invention

[0004] In response to the above situation, in order to overcome the defects of the prior art, the present invention provides a cartilage repair hydrogel material and a preparation method thereof. In order to solve the problems of weak mechanical properties, poor cell affinity and weak bone regeneration ability of the hydrogel, the present invention proposes to improve the mechanical properties and biological activity of the hydrogel by compounding silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid, and at the same time add 2,4-toluene diisocyanate-modified T-ZIF-8 and SIKVAV peptide-modified Mg-MOF to improve the antibacterial property of the hydrogel, increase the affinity of the hydrogel with bone cells, and further promote the regeneration of bone cells. The water-soluble derivative of vitamin E, D-α-tocopheryl polyethylene glycol 1000 succinate, is added to improve its anti-inflammatory and antioxidant properties.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows: The present invention proposes a method for preparing a cartilage repair hydrogel material, characterized in that the preparation method comprises the following steps:

[0006] S1. Slice the silkworm cocoon and grind it through a 100-mesh sieve, add deionized water and mix, extract at 90-100° C. for 8-10 hours, extract 2-3 times, combine the extracts and filter to obtain a filtrate, concentrate the filtrate by rotary evaporation at 50-60° C. to 30-40% of the filtrate volume to obtain a concentrate, add trypsin, and perform enzymatic hydrolysis at 32-36° C. for 3-5 hours to obtain an enzymatic hydrolyzate, place the enzymatic hydrolyzate in an autoclave, inactivate the enzyme in a boiling water bath for 12-16 minutes, cool to room temperature, centrifuge at 5000-7000 rpm for 8-10 minutes, take the supernatant, pass the supernatant through a 0.22 μm filter membrane, and irradiate with ultraviolet light for 20-30 minutes to obtain a silk fibroin peptide solution for standby use;

[0007] S2. Dissolve the oxidized chondroitin sulfate in a phosphate buffer solution with a pH of 7.5 and a concentration of 0.01 mol / L for 1-2 hours, add the silk fibroin peptide solution under a nitrogen atmosphere, heat to 65-75° C., and stir evenly to obtain the silk fibroin peptide / oxidized chondroitin sulfate, which is set aside.

[0008] S3, dissolving 3-aminophenylboronic acid in dimethyl sulfoxide to obtain a 3-aminophenylboronic acid solution; adding the 3-aminophenylboronic acid solution to the silk fibroin peptide / oxidized chondroitin sulfate obtained in S2 under an argon atmosphere, adding 1-ethyl-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide, raising the temperature to 70-80° C., and stirring at 6000-8000 rpm for 20-30 min to obtain silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid, which is set aside;

[0009] S4, dissolving T-ZIF-8 in a mixed solvent of dichloromethane and methanol in a volume ratio of 4:1, adding 2,4-toluene diisocyanate, stirring at 3000-5000 rpm for 2-3 hours, filtering, taking the precipitate, and drying it at 80°C for 5-6 hours to obtain 2,4-toluene diisocyanate-modified T-ZIF-8, which is set aside;

[0010] S5. Dissolve Mg-MOF in deionized water, add SIKVAV peptide, stir magnetically at 1000-2000 rpm for 10-14 h, centrifuge at 10000-15000 rpm for 8-14 min, take the precipitate, wash it with deionized water 2-3 times, and vacuum dry it to obtain SIKVAV peptide-modified Mg-MOF for later use;

[0011] S6. Add D-α-tocopheryl polyethylene glycol 1000 succinate, 2,4-toluene diisocyanate-modified T-ZIF-8 and SIKVAV peptide-modified Mg-MOF to the silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid obtained in S3, and cross-link under ultraviolet light to obtain a cartilage repair hydrogel material.

[0012] Preferably, in S1, the material-liquid ratio of the silkworm cocoons to the ionized water is 1 g:16-20 mL;

[0013] Preferably, in S1, the amount of trypsin added is 0.4-0.8% of the mass of the silkworm cocoon;

[0014] Preferably, in S2, the amount of the oxidized chondroitin sulfate added to the phosphate buffered saline solution is 0.3-0.5 g / mL;

[0015] Preferably, in S2, the mass volume ratio of the oxidized sulfated cartilage and the silk fibroin peptide solution is 1-2 g:10-12 mL;

[0016] Preferably, in S2, the method for preparing oxidized chondroitin sulfate specifically comprises the following steps:

[0017] Dispersing chondroitin sulfate in anhydrous ethanol to obtain a chondroitin sulfate dispersion, dissolving sodium periodate in distilled water to obtain a sodium periodate aqueous solution, mixing the chondroitin sulfate dispersion and the sodium periodate aqueous solution, reacting for 3-5 hours in an ice bath in the dark, centrifuging at 2000-3000 rpm for 20-30 minutes, dialyzing using a dialysis bag with a molecular weight cutoff of 5 kD for 68-74 hours, and lyophilizing the dialyzate to obtain oxidized chondroitin sulfate;

[0018] Preferably, the mass volume ratio of the chondroitin sulfate to anhydrous ethanol is 10-15 g:50-60 mL;

[0019] Preferably, the mass volume ratio of the sodium periodate to distilled water is 5-6 g:30-50 mL;

[0020] Chondroitin sulfate is a natural polysaccharide with good cell affinity. Chondroitin sulfate can combine with silk fibroin peptide components to maintain the healthy structure of the cartilage matrix, enhance the compression resistance and elasticity of the cartilage, and help restore the function of damaged cartilage.

[0021] Preferably, in S3, the mass volume ratio of the 3-aminophenylboronic acid to dimethyl sulfoxide is 8-10 g:40-50 mL;

[0022] Preferably, in S3, the volume mass ratio of the 3-aminophenylboronic acid solution, 1-ethyl-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide is 10-20 mL: 0.1-0.2 g: 0.08-0.12 g;

[0023] Preferably, in S4, the preparation method of T-ZIF-8 specifically comprises the following steps:

[0024] Dissolving zinc nitrate hexahydrate in methanol to obtain a zinc nitrate solution, and dissolving 2-methylimidazole in methanol to obtain a 2-methylimidazole solution; dispersing the zinc nitrate solution into the 2-methylimidazole solution, stirring for 1-2 minutes, and centrifuging at 10,000-15,000 rpm for 8-12 minutes. Taking the precipitate, washing it with methanol and deionized water 2-3 times, and vacuum drying it to obtain ZIF-8; heat-treating ZIF-8 in an oxygen atmosphere at 200° C. for 4-5 hours to obtain T-ZIF-8;

[0025] Preferably, the amount of zinc nitrate hexahydrate dissolved in methanol is 28-32 mg / mL;

[0026] Preferably, the amount of 2-methylimidazole added to methanol is 30-35 mg / mL;

[0027] Preferably, in S4, the amount of T-ZIF-8 added to the mixed solvent of dichloromethane and methanol is 10-12 mg / mL;

[0028] Preferably, in S4, the mass volume ratio of the T-ZIF-8 to 2,4-toluene diisocyanate is 100-120 mg:1 mL.

[0029] Preferably, in S5, the preparation method of the Mg-MOF specifically comprises the following steps:

[0030] 2,5-Dihydroxyterephthalic acid, Mg(NO3)2·6H2O and polyvinylpyrrolidone were added to N,N-dimethylacetamide, ultrasonically dispersed, and ammonia water was added. The mixture was heated at 100-120°C for 8-10 hours, centrifuged at 8000-10000 rpm for 6-10 minutes, and the precipitate was washed with acetone and deionized water 2-3 times, and vacuum dried to obtain Mg-MOF.

[0031] Preferably, the mass ratio of the 2,5-dihydroxyterephthalic acid, Mg(NO3)2·6H2O and polyvinylpyrrolidone is 15-17 mg:28-30 mg:10-12 mg;

[0032] Preferably, the amount of polyvinyl pyrrolidone added to N,N-dimethylacetamide is 1.5-1.7 mg / mL;

[0033] Preferably, the volume ratio of ammonia water to N,N-dimethylacetamide is 1 mL:100-120 mL;

[0034] Preferably, in S5, the amount of Mg-MOF added to deionized water is 1-1.4 mg / mL;

[0035] Preferably, in S5, the mass ratio of the Mg-MOF to the SIKVAV peptide is 100 mg:1-1.2 mg;

[0036] Preferably, in S6, the volume mass ratio of the silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid, D-α-tocopheryl polyethylene glycol 1000 succinate, WYRGRL-modified ZIF-8 and SIKVAV-modified Mg-MOF is 100 mL: 0.01-0.05 g: 0.5-0.7 g: 0.1-0.2 g.

[0037] The present invention provides a cartilage repair hydrogel material prepared by the above preparation method.

[0038] The beneficial effects achieved by the present invention are as follows:

[0039] The present invention uses silk fibroin peptide, oxidized chondroitin sulfate, and 3-aminophenylboronic acid as main materials, and simultaneously adds 2,4-toluene diisocyanate-modified T-ZIF-8 and SIKVAV peptide-modified Mg-MOF and vitamin E water-soluble derivative D-α-tocopheryl polyethylene glycol 1000 succinate. The components act synergistically to obtain a hydrogel material for cartilage repair that has good mechanical properties and cell affinity, is antibacterial and anti-inflammatory, and promotes bone cell regeneration.

[0040] 1. Silk fibroin peptide has good structural stability and biocompatibility. It exists as a scaffold support material in the hydrogel material, providing support for the growth of chondrocytes. Compared with silk fibroin, silk fibroin peptide contains specific bioactive peptide segments, which can induce chondrocytes to differentiate into chondrocytes and help chondrocytes better express cartilage-specific genes. Because the peptide segments are smaller, they can more easily penetrate into the cells and bind to receptors on the surface of chondrocytes, promoting the adhesion and proliferation of chondrocytes, which is beneficial to the growth and reproduction of chondrocytes during the repair process, and accelerating the formation and repair process of cartilage tissue;

[0041] 2. After aldehyde modification, chondroitin sulfate still retains functional carboxyl groups and sulfate groups. The carboxyl groups can form stable chemical bonds with bioactive substances such as growth factors and drugs. The carboxyl groups in oxidized chondroitin sulfate react with the amino groups in the cartilage matrix to undergo amidation reaction, thereby achieving adhesion of the hydrogel to the damaged cartilage matrix and improving the stability of the hydrogel material. The sulfate groups make the oxidized chondroitin sulfate negatively charged, and the negative charge density on the hydrogel surface increases, causing the isoelectric point of the hydrogel material to shift to a lower pH value. It can attract more water molecules through hydrogen bond interactions, resulting in increased hydrophilicity and improved stability in aqueous solution. The increased hydrophilicity leads to an increase in the viscosity of the hydrogel, which is beneficial to improving its gel strength.

[0042] 3. By adding 3-aminophenylboronic acid, a Schiff base reaction occurs between the aldehyde groups of oxidized chondroitin sulfate and the amino groups of 3-aminophenylboronic acid, which helps improve the stability of the hydrogel material with a complex three-dimensional cross-linked structure and increase its porosity. This allows the water-soluble vitamin E derivative D-α-tocopheryl polyethylene glycol 1000 succinate to stably adhere to the porous surface through the complex pores, improving its anti-inflammatory and antioxidant properties. Furthermore, the introduction of boric acid groups forms borate ester bonds with the hydroxyl groups on the metal surface. The introduction of borate ester bonds creates adhesion groups on the hydrogel surface, providing more binding sites, increasing the binding opportunities between bone cells and the hydrogel surface, and achieving the technical effect of promoting cell adhesion.

[0043] 4. T-ZIF-8 is obtained by heat-treating ZIF-8 at high temperature in an oxygen atmosphere, exposing more hydroxyl groups on its surface. On the one hand, hydroxyl groups can improve the hydrophilicity of the hydrogel, promote cell attachment and proliferation, thereby improving the compatibility of the hydrogel material with biological tissues, reducing the rejection of metal materials by tissues, helping to reduce inflammatory reactions and promote wound healing; on the other hand, the surface of T-ZIF-8 after high temperature heat treatment is negatively charged, which can react with positively charged Ca in physiological fluids. 2+ The combination forms amorphous calcium phosphate, which is beneficial to further improve the cartilage repair ability of the hydrogel material; adding 2,4-toluene diisocyanate, a stable ester bond is formed between the hydroxyl group on the surface of T-ZIF-8 and the carbon-oxygen double bond of 2,4-toluene diisocyanate, and the 2,4-toluene diisocyanate-modified T-ZIF-8 selectively migrates to the tendon, releasing zinc ions, improving its antibacterial and antimicrobial properties, promoting collagen secretion, and promoting tendon repair; at the same time, the SIKVAV peptide-modified Mg-MOF migrates to the cartilage, releasing magnesium ions, inducing cell differentiation, and promoting cartilage regeneration. The two work synergistically to improve the cell affinity of the hydrogel material and promote bone cell regeneration. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 Graph showing the test results of tensile strength and elongation at break of the hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 of the present invention;

[0045] Figure 2 Graph showing the compressive strength and elastic modulus test results of the hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 of the present invention;

[0046] Figure 3 Graph showing porosity test results of hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 of the present invention;

[0047] Figure 4 Graph showing the test results of cell adhesion performance of hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 of the present invention;

[0048] Figure 5 Graph showing the antibacterial performance test results of the hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 of the present invention;

[0049] Figure 6 This is a SEM image of the hydrogel material prepared in Example 1 of the present invention;

[0050] Figure 7 This is the SEM image of T-ZIF-8 modified with 2,4-toluene diisocyanate prepared in Example 1 of the present invention.

[0051] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as those familiar to those skilled in the art. Furthermore, any methods and materials similar or equivalent to those described herein can be applied to the present invention. The preferred embodiments and materials described herein are for illustrative purposes only and are not intended to limit the scope of this application.

[0054] The experimental methods in the following examples are conventional methods unless otherwise specified; the experimental materials used in the following examples are purchased from commercial channels unless otherwise specified. Example

[0055] A method for preparing a cartilage repair hydrogel material comprises the following steps:

[0056] S1. Crush 10 g of mulberry cocoon slices and pass them through a 100-mesh sieve, add 160 mL of deionized water and mix, extract at 90 ° C for 8 h, extract twice, combine the extracts and filter to obtain a filtrate, concentrate the filtrate by rotary evaporation at 50 ° C to 30% of the filtrate volume to obtain a concentrate, add 0.04 g of trypsin, and enzymatically hydrolyze at 32 ° C for 3 h to obtain an enzymatic solution, place the enzymatic solution in an autoclave, inactivate the enzyme in a boiling water bath for 12 min, cool to room temperature, centrifuge at 5000 rpm for 8 min, take the supernatant, pass the supernatant through a 0.22 μm filter membrane, and irradiate with ultraviolet light for 20 min to obtain a silk fibroin peptide solution for standby use;

[0057] S2. Dissolve 10 g of oxidized chondroitin sulfate in 33.3 mL of phosphate buffered saline (pH 7.5, concentration 0.01 mol / L) for 1 h, add 100 mL of silk fibroin peptide solution under nitrogen atmosphere, heat to 65° C., and stir evenly to obtain silk fibroin peptide / oxidized chondroitin sulfate, which is set aside.

[0058] S3. Dissolve 8 g of 3-aminophenylboronic acid in 40 mL of dimethyl sulfoxide to obtain a 3-aminophenylboronic acid solution; add the 3-aminophenylboronic acid solution to the silk fibroin peptide / oxidized chondroitin sulfate obtained in S2 under an argon atmosphere, add 0.48 g of 1-ethyl-(3-dimethylaminopropyl)carbodiimide and 0.384 g of N-hydroxysuccinimide, heat to 70° C., and stir at 6000 rpm for 20 min to obtain silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid, which is set aside;

[0059] S4. Dissolve 1 g of T-ZIF-8 in 100 mL of a mixed solvent of dichloromethane and methanol in a volume ratio of 4:1, add 10 mL of 2,4-toluene diisocyanate, and stir at 3000 rpm for 2 h. Filter the precipitate and dry it at 80° C. for 5 h to obtain 2,4-toluene diisocyanate-modified T-ZIF-8, which is set aside.

[0060] S5. Dissolve 0.5 g of Mg-MOF in 500 mL of deionized water, add 5 mg of SIKVAV peptide, stir magnetically at 1000 rpm for 10 h, centrifuge at 10,000 rpm for 8 min, take the precipitate, wash it twice with deionized water, and vacuum dry it to obtain SIKVAV peptide-modified Mg-MOF for later use;

[0061] S6. Add 0.01g D-α-tocopheryl polyethylene glycol 1000 succinate, 0.5g 2,4-toluene diisocyanate-modified T-ZIF-8 and 0.1g SIKVAV peptide-modified Mg-MOF to 100ml S3 of silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid, and cross-link under ultraviolet light to obtain a cartilage repair hydrogel material.

[0062] The surface morphology of the hydrogel material prepared in Example 1 was observed using a scanning electron microscope. Figure 6 The SEM image of the hydrogel material prepared in Example 1 of the present invention; the surface morphology of the 2,4-toluene diisocyanate-modified T-ZIF-8 prepared in Example 1 was observed using a scanning electron microscope. Figure 7 This is the SEM image of T-ZIF-8 modified with 2,4-toluene diisocyanate prepared in Example 1 of the present invention.

[0063] The preparation method of oxidized chondroitin sulfate specifically comprises the following steps:

[0064] Disperse 10 g of chondroitin sulfate in 50 mL of anhydrous ethanol to obtain a chondroitin sulfate dispersion, dissolve 5 g of sodium periodate in 30 mL of distilled water to obtain a sodium periodate aqueous solution, mix the chondroitin sulfate dispersion and the sodium periodate aqueous solution, react in a light-proof ice bath for 3 h, centrifuge at 2000 rpm for 20 min, dialyze using a dialysis bag with a molecular weight cutoff of 5 kD for 68 h, and freeze-dry the dialyzate to obtain oxidized chondroitin sulfate.

[0065] The preparation method of T-ZIF-8 specifically comprises the following steps:

[0066] 1 g of zinc nitrate hexahydrate was dissolved in 35.7 mL of methanol to obtain a zinc nitrate solution, and 0.5 g of 2-methylimidazole was dissolved in 16.6 mL of methanol to obtain a 2-methylimidazole solution; the zinc nitrate solution was dispersed in the 2-methylimidazole solution, stirred for 1 min, and centrifuged at 10,000 rpm for 8 minutes. The precipitate was taken, washed twice with methanol and deionized water, and vacuum dried to obtain ZIF-8; ZIF-8 was heat treated in an oxygen atmosphere at 200°C for 4 h to obtain T-ZIF-8.

[0067] The preparation method of Mg-MOF specifically includes the following steps:

[0068] 150 mg of 2,5-dihydroxyterephthalic acid, 280 mg of Mg(NO3)2·6H2O and 100 mg of polyvinylpyrrolidone were added to 66.7 mL of N,N-dimethylacetamide, ultrasonically dispersed, 0.6 mL of ammonia water was added, heated at 100°C for 8 h, centrifuged at 8000 rpm for 6 min, and the precipitate was taken, washed twice with acetone and deionized water, and vacuum dried to obtain Mg-MOF. Example

[0069] A method for preparing a cartilage repair hydrogel material comprises the following steps:

[0070] S1. Crush 10 g of mulberry cocoon slices and pass them through a 100-mesh sieve, add 180 mL of deionized water and mix, extract at 95 ° C for 9 h, extract twice, combine the extracts and filter to obtain a filtrate, concentrate the filtrate by rotary evaporation at 55 ° C to 35% of the filtrate volume to obtain a concentrate, add 0.06 g of trypsin, and enzymatically hydrolyze at 34 ° C for 4 h to obtain an enzymatic solution, place the enzymatic solution in an autoclave, inactivate the enzyme in a boiling water bath for 14 min, cool to room temperature, and centrifuge at 6000 rpm for 9 min. Take the supernatant, pass the supernatant through a 0.22 μm filter membrane, and irradiate with ultraviolet light for 25 min to obtain a silk fibroin peptide solution for standby use;

[0071] S2. Dissolve 15 g of oxidized chondroitin sulfate in 37.5 mL of phosphate buffered saline (pH 7.5, concentration 0.01 mol / L) for 1.5 h, add 110 mL of silk fibroin peptide solution under nitrogen atmosphere, heat to 70° C., and stir evenly to obtain silk fibroin peptide / oxidized chondroitin sulfate, which is set aside.

[0072] S3. Dissolve 9 g of 3-aminophenylboronic acid in 45 mL of dimethyl sulfoxide to obtain a 3-aminophenylboronic acid solution; add the 3-aminophenylboronic acid solution to the silk fibroin peptide / oxidized chondroitin sulfate obtained in S2 under an argon atmosphere, add 0.54 g of 1-ethyl-(3-dimethylaminopropyl)carbodiimide and 0.36 g of N-hydroxysuccinimide, heat to 75° C., and stir at 7000 rpm for 25 min to obtain silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid, which is set aside;

[0073] S4, dissolving 1.1 g of T-ZIF-8 in 100 mL of a mixed solvent of dichloromethane and methanol in a volume ratio of 4:1, adding 10 mL of 2,4-toluene diisocyanate, stirring at 4000 rpm for 2.5 h, filtering, taking the precipitate, and drying it at 80° C. for 5.5 h to obtain 2,4-toluene diisocyanate-modified T-ZIF-8, which was set aside;

[0074] S5. Dissolve 0.6 g of Mg-MOF in 500 mL of deionized water, add 6.6 mg of SIKVAV peptide, and stir magnetically at 1000 rpm for 12 h. Centrifuge at 12500 rpm for 12 min. Take the precipitate, wash it twice with deionized water, and vacuum dry it to obtain SIKVAV peptide-modified Mg-MOF for later use.

[0075] S6. Add 0.03g D-α-tocopheryl polyethylene glycol 1000 succinate, 0.6g 2,4-toluene diisocyanate-modified T-ZIF-8 and 0.15g SIKVAV peptide-modified Mg-MOF to 100ml S3 of silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid, and cross-link under ultraviolet light to obtain a cartilage repair hydrogel material.

[0076] The preparation methods of oxidized chondroitin sulfate, T-ZIF-8 and Mg-MOF can be referred to Example 1. Example

[0077] S1. Crush 10 g of mulberry cocoon slices through a 100-mesh sieve, add 200 mL of deionized water and mix, extract at 10 ° C for 10 h, extract three times, combine the extracts and filter to obtain a filtrate, concentrate the filtrate by rotary evaporation at 60 ° C to 40% of the filtrate volume to obtain a concentrate, add 0.08 g of trypsin, and perform enzymatic hydrolysis at 36 ° C for 5 h to obtain an enzymatic solution, place the enzymatic solution in an autoclave, inactivate the enzyme in a boiling water bath for 16 min, cool to room temperature, centrifuge at 7000 rpm for 10 min, take the supernatant, pass the supernatant through a 0.22 μm filter membrane, and irradiate with ultraviolet light for 30 min to obtain a silk fibroin peptide solution for standby use;

[0078] S2. Dissolve 20 g of oxidized chondroitin sulfate in 40 mL of phosphate buffered saline (pH 7.5, concentration 0.01 mol / L) for 2 h, add 120 mL of silk fibroin peptide solution under nitrogen atmosphere, heat to 75° C., and stir evenly to obtain silk fibroin peptide / oxidized chondroitin sulfate, which is set aside.

[0079] S3. Dissolve 10 g of 3-aminophenylboronic acid in 50 mL of dimethyl sulfoxide to obtain a 3-aminophenylboronic acid solution. Add the 3-aminophenylboronic acid solution to the silk fibroin peptide / oxidized chondroitin sulfate obtained in S2 under an argon atmosphere, add 0.6 g of 1-ethyl-(3-dimethylaminopropyl)carbodiimide and 0.36 g of N-hydroxysuccinimide, heat to 80° C., and stir at 8000 rpm for 30 min to obtain silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid, which is set aside.

[0080] S4, dissolving 1.2 g of T-ZIF-8 in 100 mL of a mixed solvent of dichloromethane and methanol in a volume ratio of 4:1, adding 10 mL of 2,4-toluene diisocyanate, stirring at 5000 rpm for 3 h, filtering, taking the precipitate, and drying it at 80° C. for 6 h to obtain 2,4-toluene diisocyanate-modified T-ZIF-8, which was set aside;

[0081] S5. Dissolve 0.7 g of Mg-MOF in 500 mL of deionized water, add 8.4 mg of SIKVAV peptide, and stir magnetically at 1000 rpm for 14 h. Centrifuge at 15000 rpm for 14 min. Take the precipitate, wash it three times with deionized water, and vacuum dry it to obtain SIKVAV peptide-modified Mg-MOF for later use.

[0082] S6. Add 0.05g D-α-tocopheryl polyethylene glycol 1000 succinate, 0.7g 2,4-toluene diisocyanate-modified T-ZIF-8 and 0.2g SIKVAV peptide-modified Mg-MOF to 100ml S3 of silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid, and cross-link under ultraviolet light to obtain a cartilage repair hydrogel material.

[0083] The preparation methods of oxidized chondroitin sulfate, T-ZIF-8 and Mg-MOF can be referred to Example 1.

[0084] Comparative Example 1

[0085] This comparative example provides a cartilage repair hydrogel material and a preparation method thereof. The only difference between the comparative example and Example 1 is that the chondroitin sulfate is not subjected to oxidation treatment, and the other components and component contents are the same as those in Example 1.

[0086] Comparative Example 2

[0087] This comparative example provides a cartilage repair hydrogel material and a preparation method thereof, which differs from Example 1 only in that 3-aminophenylboronic acid is not included, and the remaining components and component contents are the same as those in Example 1.

[0088] Comparative Example 3

[0089] This comparative example provides a cartilage repair hydrogel material and a preparation method thereof. The only difference between the comparative example and Example 1 is that the ZIF-8 surface is not subjected to high-temperature heat treatment and 2,4-toluene diisocyanate is not grafted. The remaining components and component contents are the same as those in Example 1.

[0090] Comparative Example 4

[0091] This comparative example provides a cartilage repair hydrogel material and a preparation method thereof, which differs from Example 1 only in that SIKVAV peptide-modified Mg-MOF is not included, and the remaining components and component contents are the same as those in Example 1.

[0092] Performance testing and result analysis

[0093] 1. Mechanical properties test of hydrogel materials

[0094] Test method: The hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 were extruded into sample strips with a diameter of 20 mm × 10 mm × 100 μm (length × width × thickness). After the samples were fully formed, they were placed in a stretching device for tensile testing at a tensile rate of 1.0 mm / min and a tensile force of 50 N. The samples were stretched until they broke, and the tensile strength and elongation at break of each group of hydrogel materials were calculated. After the orthopedic implant materials prepared in Examples 1-3 and Comparative Examples 1-4 were made into sample strips, they were placed on the platform of a universal mechanical testing machine and compressed along the long axis of the sample strip at a speed of 0.5 mm / min. The compression was stopped when the deformation was 10%, and the compressive strength and elastic modulus were calculated.

[0095] Result analysis: Figure 1 The graph shows the test results of tensile strength and elongation at break of the hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 of the present invention. Figure 2The compressive strength and elastic modulus test results of the hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 of the present invention are shown in the figure. As shown in the figure, the tensile and compressive properties of the hydrogel materials prepared in Comparative Examples 1-4 are significantly lower than those of the hydrogel materials prepared in Examples 1-3. In Comparative Example 1, the chondroitin sulfate is not oxidized, so the chondroitin sulfate has no aldehyde group and cannot undergo a Schiff base reaction with 3-aminophenylboronic acid. Comparative Example 2 does not include 3-aminophenylboronic acid, and the hydroxyl groups on the metal surface cannot form borate ester bonds with the boronic acid groups, let alone a Schiff base reaction with oxidized chondroitin sulfate, thereby reducing the degree of cross-linking between the components. Therefore, the mechanical properties of the hydrogel materials prepared in Comparative Examples 1 and 2 are reduced. Comparative Example 4 does not include any Mg-MOF and lacks the support of the metal material, which will reduce the mechanical properties.

[0096] 2. Porosity test of hydrogel materials

[0097] Test method: The dry hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 were immersed in anhydrous ethanol until the ethanol completely filled the pores of the cartilage repair hydrogel material. The cartilage repair hydrogel material was then transferred to a graduated cylinder containing ethanol with a known initial volume v1 and weight m1, respectively. The volumes and weights of the hydrogel material and ethanol in the graduated cylinder were recorded as v2 and m2, respectively. The porosity was calculated according to the following formula:

[0098] ;

[0099] Result analysis: Figure 3 The porosity test results of the hydrogel materials prepared in Examples 1-3 of the present invention and Comparative Examples 1-4 are shown. As shown in the figure, the porosities of the hydrogel materials prepared in Examples 1-3 are 94.2%, 93.6% and 92.8%, respectively, which are significantly higher than the porosity of the hydrogel materials prepared in Comparative Examples 1-4. This is because a Schiff base reaction occurs between the aldehyde group of oxidized chondroitin sulfate and the amino group of 3-aminophenylboronic acid in the hydrogel materials prepared in Examples 1-3, thereby improving the stability of the hydrogel material with a three-dimensional complex cross-linked structure and increasing its porosity. A stable ester bond is formed between the hydroxyl group on the surface of T-ZIF-8 and the carbon-oxygen double bond of 2,4-toluene diisocyanate. Mg-MOF is modified with SIKVAV peptide to increase the surface size of Mg-MOF. The components work synergistically to obtain a highly stable hydrogel material with a porous cross-linked structure.

[0100] 3. Cell adhesion performance test of hydrogel materials:

[0101] Testing method: MC3T3-E1 mouse embryonic osteoblasts were selected as experimental cells and cultured in DMEM medium containing 10% fetal bovine serum and 1% penicillin / streptomycin. The osteoblasts were co-cultured on the hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 in a 96-well plate for 24 hours. After removal, the cells were repeatedly washed with PBS buffer to remove cells that failed to attach successfully. In the dark, 30 μL of CCK-8 solution and 300 μL of culture medium were added to each well. The cells were cultured for another 12 hours, and 100 μL of the supernatant was aspirated and the absorbance (OD) was measured using a microplate reader at a wavelength of 450 nm. The cell adhesion rate was calculated according to the following formula: Adhesion rate = (number of adhered cells / total number of cells) × 100%.

[0102] Result analysis: Figure 4 The cell adhesion performance test results of the hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 of the present invention are shown in the figure. As shown in the figure, the cell adhesion rates of the hydrogel materials prepared in Examples 1-3 reached 31.8%, 32.5% and 33.6%, respectively, while the cell adhesion rates of the hydrogel materials prepared in Comparative Examples 1-4 were only 22.7%, 24.3%, 27.1% and 25.2%, respectively. This is because the carboxyl groups in the oxidized chondroitin sulfate in the hydrogel materials prepared in Examples 1-3 undergo amidation reaction with the amino groups in the cartilage matrix, thereby achieving adhesion of the hydrogel to the damaged cartilage matrix and improving the stability of the hydrogel material. Boric acid groups are introduced by adding 3-aminophenylboronic acid to form borate ester bonds with the hydroxyl groups on the metal surface. The introduction of borate ester bonds creates adhesion groups on the surface of the hydrogel material, can provide more binding sites, increase the binding opportunities of bone cells to the surface of the hydrogel material, and achieve the technical effect of promoting cell adhesion. The surface of T-ZIF-8 obtained after high-temperature heat treatment of ZIF-8 is negatively charged and can react with positively charged Ca in physiological fluids. 2+ The combination forms amorphous calcium phosphate, thereby improving the adhesion of the hydrogel material to bone cells, which is beneficial to further improve the cartilage repair ability of the hydrogel material.

[0103] 4. Antibacterial performance test of hydrogel materials:

[0104] Test method: The hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 were placed in corresponding groups on a 48-well plate, with 3 samples in each group. The concentration of Staphylococcus aureus liquid was adjusted to 10 6CFU / mL, then add 300μL of Staphylococcus aureus liquid to each well and cover with sterile PE film, flattening the liquid to evenly cover the sample surface. To prevent evaporation of the liquid on the sample surface, add sterile water to the gaps around the 48-well plate at a humidity of 95%. After incubation in a 37°C electric constant temperature incubator for 6 hours, the bacteria on the sample surface are eluted with PBS solution and collected. 100μL of the eluate is aspirated and dropped onto a nutrient agar plate, spread evenly, and incubated inverted at 37°C for 24 hours. The plate is then removed and photographed using an automatic colony analyzer to count the number of viable colonies and test its antibacterial properties.

[0105] Result analysis: Figure 5 The antibacterial performance test results of the hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 of the present invention are shown in the figure. As shown in the figure, the antibacterial rates of the hydrogel materials prepared in Examples 1-3 reached 86.1%, 85.4% and 87.2%, respectively, while the antibacterial rates of the hydrogel materials prepared in Comparative Examples 1-4 were only 82.4%, 83.6%, 67.5% and 81.3%, respectively. The borate bond and oxidized chondroitin sulfate have antibacterial properties, so the antibacterial rates of Comparative Examples 1-2 and 4 will decrease; in the hydrogel material prepared in Comparative Example 3, ZIF-8 is not subjected to high-temperature heat treatment, so no more hydroxyl groups are exposed on the surface, and a stable ester bond cannot be formed with the carbon-oxygen double bond of 2,4-toluene diisocyanate, thereby reducing the antibacterial rate. This shows that grafting 2,4-toluene diisocyanate on the surface of ZIF-8 after high-temperature heat treatment releases zinc ions, which can improve the antibacterial and antibacterial properties of the hydrogel material.

[0106] Animal cartilage repair experiment

[0107] Establishment of cartilage defect model: 80 SD rats weighing 200-250 g were selected. The rats were fasted for 12 h and fasted for 3 h before surgery and randomly divided into 7 groups, 10 rats in each group, namely Example 1-3 group, Comparative Example 1-4 group and blank control group; the rats were anesthetized by intraperitoneal injection of 10% chloral hydrate solution (800 μL / rat), the right knee joint of the rats was selected as the experimental site, the right knee joint was completely depilated using a disposable skin preparation blade, and the exposed skin was disinfected with iodine solution using a sterile medical cotton swab, and then the skin was wiped with 75% medical alcohol for deiodination. A cylindrical full-thickness cartilage defect with a diameter of 2 mm and a depth of 3 mm was made in the right knee joint of the rat using sterile surgical scissors, the depth reaching the subchondral bone. After removing the blood clot in the defect, the Example 1-3 group and the Comparative Example 1-4 group were The hydrogel materials prepared in Examples 1-3 and Comparative Examples 1-4 were implanted, and a handheld ultraviolet curing light was used to illuminate the defect for 20 seconds to completely crosslink the precursor solution to form a hydrogel scaffold. No material was implanted in the blank control group. After the treatment, the ligaments and skin were sutured in sequence, the wounds were disinfected with iodine solution, and penicillin G sodium antibiotic solution (120 mg / animal) was injected. The animals were observed at all times until they woke up from anesthesia and were returned to the cages. They were raised individually in separate cages and continuously injected with penicillin G sodium antibiotic solution for 2 days at the same dose. The affected limbs were not immobilized and moved normally. They were fed with standard pellet feed after surgery and had free access to water. The conditions were observed daily. If any abnormalities were found, they were treated promptly. CT examinations were performed 12 weeks later to observe the repair of the bone and cartilage, and the following scoring was used. The specific scoring criteria are shown in Table 1:

[0108] Table 1 Scoring criteria

[0109]

[0110] The results of the animal cartilage repair experiment are shown in Table 2:

[0111] Table 2 Animal cartilage repair experimental results

[0112]

[0113] Result analysis: From the results of the animal cartilage repair experiment in Table 2, it can be seen that the hydrogel materials prepared in Examples 1-3 of the present invention repaired the defective tissue in the same manner as the surrounding normal cartilage, with no obvious boundary integration, a smooth surface of the overall structure, and an overall repair evaluation score of 11.2-11.4 points, reaching the I-level repair level and completely restoring the normal structure; this indicates that the silk fibroin peptide is more likely to penetrate into the cells, bind to the receptors on the surface of the chondrocytes, promote the adhesion and proliferation of the chondrocytes, and is beneficial to the growth and reproduction of the chondrocytes during the repair process, thereby accelerating the formation and repair process of the cartilage tissue; the carboxyl groups in the oxidized chondroitin sulfate react with the amino groups in the cartilage matrix to achieve adhesion of the hydrogel to the damaged cartilage matrix; the introduction of the boric acid group forms a borate ester bond with the hydroxyl groups on the metal surface, creates an adhesion group on the surface of the hydrogel material, provides more binding sites, increases the binding opportunity of bone cells to the surface of the hydrogel material, and achieves the technical effect of promoting cell adhesion; the surface of T-ZIF-8 after high-temperature heat treatment is negatively charged, and can react with the positively charged Ca in physiological fluids. 2+ The combination to form amorphous calcium phosphate is beneficial to further improve the cartilage repair ability of the hydrogel material. T-ZIF-8 modified with 2,4-toluene diisocyanate selectively migrates to the tendon, releasing zinc ions, improving its antibacterial and antimicrobial properties, promoting collagen secretion, and promoting tendon repair; at the same time, Mg-MOF modified with SIKVAV peptide migrates to the cartilage, releasing magnesium ions, inducing cell differentiation, and promoting cartilage regeneration. The two work synergistically to improve the cell affinity of the hydrogel material and promote bone cell regeneration.

[0114] While the embodiments of the present invention have been shown and described, it will be apparent to those skilled in the art that various changes, modifications, substitutions, and alterations can be made to the embodiments without departing from the principles and spirit of the invention.

[0115] The present invention and its embodiments are described above. Such description is not restrictive. The drawings show only one embodiment of the present invention, and actual applications are not limited thereto. In short, if a person skilled in the art is inspired by the above, and does not deviate from the purpose of the present invention, any method and embodiment similar to the technical solution without creative design shall fall within the scope of protection of the present invention.

Claims

1. A method for preparing a cartilage repair hydrogel material, characterized by: The preparation method comprises the following steps: S1. Slice the silkworm cocoon and grind it through a 100-mesh sieve, add deionized water and mix, extract at 90-100° C. for 8-10 hours, extract 2-3 times, combine the extracts and filter to obtain a filtrate, concentrate the filtrate by rotary evaporation at 50-60° C. to 30-40% of the filtrate volume to obtain a concentrate, add trypsin, and perform enzymatic hydrolysis at 32-36° C. for 3-5 hours to obtain an enzymatic hydrolyzate, place the enzymatic hydrolyzate in an autoclave, inactivate the enzyme in a boiling water bath for 12-16 minutes, cool to room temperature, centrifuge at 5000-7000 rpm for 8-10 minutes, take the supernatant, pass the supernatant through a 0.22 μm filter membrane, and irradiate with ultraviolet light for 20-30 minutes to obtain a silk fibroin peptide solution for standby use; S2. Dissolve the oxidized chondroitin sulfate in a phosphate buffer solution with a pH of 7.5 and a concentration of 0.01 mol / L for 1-2 hours, add the silk fibroin peptide solution under a nitrogen atmosphere, heat to 65-75° C., and stir evenly to obtain the silk fibroin peptide / oxidized chondroitin sulfate, which is set aside. S3, dissolving 3-aminophenylboronic acid in dimethyl sulfoxide to obtain a 3-aminophenylboronic acid solution; adding the 3-aminophenylboronic acid solution to the silk fibroin peptide / oxidized chondroitin sulfate obtained in S2 under an argon atmosphere, adding 1-ethyl-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide, raising the temperature to 70-80° C., and stirring at 6000-8000 rpm for 20-30 min to obtain silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid, which is set aside; S4, dissolving T-ZIF-8 in a mixed solvent of dichloromethane and methanol in a volume ratio of 4:1, adding 2,4-toluene diisocyanate, stirring at 3000-5000 rpm for 2-3 hours, filtering, taking the precipitate, and drying at 80°C for 5-6 hours to obtain 2,4-toluene diisocyanate-modified T-ZIF-8, which is set aside; wherein the preparation method of T-ZIF-8 is to heat-treat ZIF-8 in an oxygen atmosphere at 200°C for 4-5 hours to obtain T-ZIF-8; S5. Dissolve Mg-MOF in deionized water, add SIKVAV peptide, stir magnetically at 1000-2000 rpm for 10-14 h, centrifuge at 10000-15000 rpm for 8-14 min, take the precipitate, wash it with deionized water 2-3 times, and vacuum dry it to obtain SIKVAV peptide-modified Mg-MOF for later use; S6. Add D-α-tocopheryl polyethylene glycol 1000 succinate, 2,4-toluene diisocyanate-modified T-ZIF-8 and SIKVAV peptide-modified Mg-MOF to the silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid obtained in S3, and cross-link under ultraviolet light to obtain a cartilage repair hydrogel material.

2. The method for preparing a cartilage repair hydrogel material according to claim 1, characterized in that: In S1, the material-liquid ratio of the silkworm cocoon to the ionized water is 1 g:16-20 mL; and the added amount of the trypsin is 0.4-0.8% of the mass of the silkworm cocoon.

3. The method for preparing a cartilage repair hydrogel material according to claim 2, characterized in that: In S2, the amount of the oxidized chondroitin sulfate added to the phosphate buffered saline solution is 0.3-0.5 g / mL; the mass volume ratio of the oxidized chondroitin sulfate and the silk fibroin peptide solution is 1-2 g:10-12 mL.

4. The method for preparing a cartilage repair hydrogel material according to claim 3, characterized in that: In S2, the method for preparing oxidized chondroitin sulfate specifically comprises the following steps: Dispersing chondroitin sulfate in anhydrous ethanol to obtain a chondroitin sulfate dispersion, dissolving sodium periodate in distilled water to obtain a sodium periodate aqueous solution, mixing the chondroitin sulfate dispersion and the sodium periodate aqueous solution, reacting for 3-5 hours in an ice bath in the dark, centrifuging at 2000-3000 rpm for 20-30 minutes, dialyzing using a dialysis bag with a molecular weight cutoff of 5 kD for 68-74 hours, and lyophilizing the dialyzate to obtain oxidized chondroitin sulfate; The mass volume ratio of the chondroitin sulfate to anhydrous ethanol is 10-15 g:50-60 mL; the mass volume ratio of the sodium periodate to distilled water is 5-6 g:30-50 mL.

5. The method for preparing a cartilage repair hydrogel material according to claim 4, characterized in that: In S3, the mass volume ratio of the 3-aminophenylboronic acid to dimethyl sulfoxide is 8-10 g:40-50 mL; the volume mass ratio of the 3-aminophenylboronic acid solution, 1-ethyl-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide is 10-20 mL:0.1-0.2 g:0.08-0.12 g.

6. The method for preparing a cartilage repair hydrogel material according to claim 5, characterized in that: In S4, the preparation method of T-ZIF-8 specifically comprises the following steps: Dissolving zinc nitrate hexahydrate in methanol to obtain a zinc nitrate solution, and dissolving 2-methylimidazole in methanol to obtain a 2-methylimidazole solution; dispersing the zinc nitrate solution into the 2-methylimidazole solution, stirring for 1-2 minutes, and centrifuging at 10,000-15,000 rpm for 8-12 minutes. Taking the precipitate, washing it with methanol and deionized water 2-3 times, and vacuum drying it to obtain ZIF-8; heat-treating ZIF-8 in an oxygen atmosphere at 200° C. for 4-5 hours to obtain T-ZIF-8; The amount of zinc nitrate hexahydrate dissolved in methanol is 28-32 mg / mL; the amount of 2-methylimidazole added in methanol is 30-35 mg / mL; the amount of T-ZIF-8 added in a mixed solvent of dichloromethane and methanol is 10-12 mg / mL; the mass volume ratio of T-ZIF-8 to 2,4-toluene diisocyanate is 100-120 mg:1 mL.

7. The method for preparing a cartilage repair hydrogel material according to claim 6, characterized in that: In S5, the preparation method of the Mg-MOF specifically comprises the following steps: 2,5-Dihydroxyterephthalic acid, Mg(NO3)2·6H2O and polyvinylpyrrolidone were added to N,N-dimethylacetamide, ultrasonically dispersed, and ammonia water was added. The mixture was heated at 100-120°C for 8-10 hours, centrifuged at 8000-10000 rpm for 6-10 minutes, and the precipitate was washed with acetone and deionized water 2-3 times, and vacuum dried to obtain Mg-MOF. The mass ratio of the 2,5-dihydroxyterephthalic acid, Mg(NO3)2·6H2O and polyvinyl pyrrolidone is 15-17 mg:28-30 mg:10-12 mg; the amount of polyvinyl pyrrolidone added to N,N-dimethylacetamide is 1.5-1.7 mg / mL; the volume ratio of ammonia water to N,N-dimethylacetamide is 1 mL:100-120 mL; the amount of Mg-MOF added to deionized water is 1-1.4 mg / mL; the mass ratio of Mg-MOF to SIKVAV peptide is 100 mg:1-1.2 mg.

8. The method for preparing a cartilage repair hydrogel material according to claim 7, characterized in that: In S6, the volume mass ratio of the silk fibroin peptide / oxidized chondroitin sulfate / 3-aminophenylboronic acid, D-α-tocopheryl polyethylene glycol 1000 succinate, 2,4-toluene diisocyanate-modified ZIF-8 and SIKVAV-modified Mg-MOF is 100 mL: 0.01-0.05 g: 0.5-0.7 g: 0.1-0.2 g.

9. A cartilage repair hydrogel material, characterized by: The cartilage repair hydrogel material is prepared by the preparation method according to any one of claims 1 to 8.

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