A hydroxyapatite-based restorative material and its application in medical cosmetology

Abstract

The invention discloses a repair material based on hydroxyapatite and application thereof in medical cosmetology. The repair material comprises the following components in parts by weight: 28-40 parts of hydroxyapatite, nano-microcrystalline cellulose, 20-30 parts of modified silk fibroin, and 0.1-5 parts of antimicrobial peptide. The modified silk fibroin is prepared by cross-linking and modifying the silk fibroin with polyethylene glycol glycidyl ether, and the antimicrobial peptide is LL-37 modified with polyethylene glycol. The invention adopts hydroxyapatite, nano-microcrystalline cellulose and modified silk fibroin to composite, and adds antimicrobial peptide as an antibacterial substance to prepare a repair material with bone induction, bone conduction and degradable functions.

Description

Technical Field

[0001] The present invention relates to the technical field of artificial bone materials, in particular to a hydroxyapatite-based repair material and its application in medical cosmetology. Background Art

[0002] Trauma and repair have always been important research topics in the field of plastic surgery. At present, the deformities and defects of surface tissues and organs caused by congenital or traumatic reasons are mainly repaired by soft tissue material implantation. This method is in line with the development trend of modern medicine: "non-invasive repair" replaces "trauma repairing trauma". However, in clinical applications, it is found that after soft tissue materials are implanted into the human body, they cannot adhere to and combine with surrounding tissues, and are prone to deformation and displacement, which cannot achieve the purpose of plastic surgery and repair. The main reason for this phenomenon is that the soft tissue materials currently used have a strong hydrophobic surface, which leads to poor compatibility of tissue cells, and then fibrous connective tissue forms capsules around the materials. The capsules thicken and contract over time, and eventually cause the implanted materials to deform and shift.

[0003] Hydroxyapatite is a type of calcium-phosphate ceramic biomaterial. It is similar to the natural hydroxyapatite in human bones and tooth enamel in composition and crystal structure. It rarely causes foreign body and inflammatory reactions. It is non-toxic, non-irritating, non-rejecting, non-aging, non-sensitizing, non-carcinogenic, has excellent biocompatibility, and has a strong ability to integrate with the body when implanted. It is currently widely used in clinical practice. Hydroxyapatite can chemically combine with bone tissue, but due to its high toughness, low strength, and high brittleness of sintered block materials, it is mainly used clinically to fill cavity defects and as artificial bone for non-load-bearing parts, and its use is very limited.

[0004] Based on this, the present invention develops a hydroxyapatite-based repair material to overcome the shortcomings of existing soft tissue materials in medical cosmetology applications. Summary of the invention

[0005] The purpose of the present invention is to provide a hydroxyapatite-based repair material and its application in medical cosmetology. The present invention adopts hydroxyapatite, nano-microcrystalline cellulose and modified silk fibroin to form a composite, and adds antimicrobial peptides as antibacterial substances to prepare a repair material with bone induction, bone conduction and degradable functions.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A hydroxyapatite-based repair material comprises the following components in parts by weight: 15-25 parts of hydroxyapatite, 10-20 parts of nano-microcrystalline cellulose, 20-30 parts of modified silk fibroin, and 5-8 parts of antimicrobial peptides. The modified silk fibroin is prepared by cross-linking and modifying the silk fibroin with polyethylene glycol glycidyl ether, and the antimicrobial peptide is LL-37 modified with polyethylene glycol.

[0008] Further preferably, the hydroxyapatite is made from animal bones by calcination and has a particle size of 20-50 μm.

[0009] Further preferably, the preparation method of the repair material comprises the following steps:

[0010] S1, mixing silk fibroin and polyethylene glycol glycidyl ether in a certain proportion and then standing at room temperature for 4 to 6 hours to obtain a modified silk fibroin solution;

[0011] S2, dissolving LL-37 in a TRIS-HCl buffer solution, then adding a certain proportion of monomethoxy polyethylene glycol succinimidyl propionate to the solution, reacting at room temperature for 20 to 40 minutes, adding 1 wt % of trifluoroacetic acid to terminate the reaction, separating the mixture by cation exchange chromatography, washing and then freeze-drying to obtain an antimicrobial peptide freeze-dried powder;

[0012] S3. Add hydroxyapatite, nano-microcrystalline cellulose and antimicrobial peptide into the modified silk fibroin solution and stir thoroughly to obtain the hydroxyapatite-based repair material.

[0013] More preferably, in step S1, the molar ratio of silk fibroin to polyethylene glycol glycidyl ether is 5 to 10:1.

[0014] Further preferably, in step S2, the molar ratio of LL-37 to monomethoxy polyethylene glycol succinimidyl propionate is 1:5-8.

[0015] A hydroxyapatite-based repair material is used in medical cosmetology. The repair material is poured into a molding mold and freeze-dried at -60°C for 24 hours to obtain a repair sample. Before use, the sample is immersed in 90 v / v% methanol for 10 to 20 minutes, taken out and placed in a 37°C oven for drying.

[0016] Beneficial effects of the present invention:

[0017] The present invention adopts hydroxyapatite, nano-microcrystalline cellulose and modified silk protein composite, adds antimicrobial peptide as antibacterial substance, and prepares a repair material with bone induction, bone conduction and degradable functions. Among them, nano-microcrystalline cellulose has the characteristics of large specific surface area, high strength, low density, good dispersibility in solution, natural non-toxicity, degradability, good biological and cell compatibility, etc., and can be used as a carrier of decalcified bone matrix. Nano-microcrystalline cellulose and hydroxyapatite composite can combine the advantages of natural polymer and hydroxyapatite particles to make up for the shortcomings of both parties. The present invention adds polyethylene glycol glycidyl ether to cross-link and modify silk protein, changes the morphology of composite material particles, promotes the formation of needle-shaped hydroxyapatite, improves the crystallinity of silk protein in the composite material, and improves the mechanical properties and toughness of the composite material. The present invention adopts polyethylene glycol to modify the broad-spectrum antimicrobial peptide LL-37, which can increase the molecular weight of the polypeptide, effectively improve the resistance to enzymolysis of LL-37, thereby increasing its biological stability and extending its half-life.

[0018] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. DETAILED DESCRIPTION

[0019] The following will be combined with 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.

[0020] Example 1

[0021] A hydroxyapatite-based repair material, comprising the following components by weight: 15 parts of hydroxyapatite, 10 parts of nano-microcrystalline cellulose, 20 parts of modified silk fibroin, and 5 parts of antimicrobial peptide, wherein the modified silk fibroin is prepared by cross-linking and modifying the silk fibroin with polyethylene glycol glycidyl ether, and the antimicrobial peptide is LL-37 modified with polyethylene glycol. Hydroxyapatite is prepared by calcining stone animal bones, and the particle size is 20-50 μm.

[0022] The preparation method of the repair material comprises the following steps:

[0023] S1, mixing silk fibroin and polyethylene glycol glycidyl ether in a molar ratio of 5:1 and then standing at room temperature for 6 hours to obtain a modified silk fibroin solution;

[0024] S2, dissolving LL-37 in TRIS-HCl buffer solution, and then adding a certain proportion of monomethoxy polyethylene glycol succinimidyl propionate to the solution, the molar ratio of LL-37 to monomethoxy polyethylene glycol succinimidyl propionate is 1:5, reacting at room temperature for 40 minutes, adding 1wt% trifluoroacetic acid to terminate the reaction, separating the mixture by cation exchange chromatography, washing and then freeze-drying to obtain antimicrobial peptide freeze-dried powder;

[0025] S3. Add hydroxyapatite, nano-microcrystalline cellulose and antimicrobial peptide into the modified silk fibroin solution and stir thoroughly to obtain the hydroxyapatite-based repair material.

[0026] Example 2

[0027] A hydroxyapatite-based repair material, comprising the following components by weight: 22 parts of hydroxyapatite, 15 parts of nano-microcrystalline cellulose, 25 parts of modified silk fibroin, and 6 parts of antimicrobial peptide, wherein the modified silk fibroin is prepared by cross-linking and modifying the silk fibroin with polyethylene glycol glycidyl ether, and the antimicrobial peptide is LL-37 modified with polyethylene glycol. Hydroxyapatite is prepared by calcining stone animal bones, and the particle size is 20-50 μm.

[0028] The preparation method of the repair material comprises the following steps:

[0029] S1, mixing silk fibroin and polyethylene glycol glycidyl ether in a molar ratio of 8:1 and allowing to react at room temperature for 5 hours to obtain a modified silk fibroin solution;

[0030] S2, dissolving LL-37 in TRIS-HCl buffer solution, and then adding a certain proportion of monomethoxy polyethylene glycol succinimidyl propionate to the solution, the molar ratio of LL-37 to monomethoxy polyethylene glycol succinimidyl propionate is 1:6, reacting at room temperature for 30 minutes, adding 1wt% trifluoroacetic acid to terminate the reaction, separating the mixture by cation exchange chromatography, washing and then freeze-drying to obtain antimicrobial peptide freeze-dried powder;

[0031] S3. Add hydroxyapatite, nano-microcrystalline cellulose and antimicrobial peptide into the modified silk fibroin solution and stir thoroughly to obtain the hydroxyapatite-based repair material.

[0032] Example 3

[0033] A hydroxyapatite-based repair material, comprising the following components by weight: 25 parts of hydroxyapatite, 20 parts of nano-microcrystalline cellulose, 30 parts of modified silk fibroin, and 8 parts of antimicrobial peptide, wherein the modified silk fibroin is prepared by cross-linking and modifying the silk fibroin with polyethylene glycol glycidyl ether, and the antimicrobial peptide is LL-37 modified with polyethylene glycol. Hydroxyapatite is prepared by calcining stone animal bones, and the particle size is 20-50 μm.

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

[0035] S1, mixing silk fibroin and polyethylene glycol glycidyl ether in a molar ratio of 10:1 and then standing at room temperature for 4 hours to obtain a modified silk fibroin solution;

[0036] S2, dissolving LL-37 in TRIS-HCl buffer solution, and then adding a certain proportion of monomethoxy polyethylene glycol succinimidyl propionate to the solution, the molar ratio of LL-37 to monomethoxy polyethylene glycol succinimidyl propionate is 1:8, reacting at room temperature for 20 minutes, adding 1wt% trifluoroacetic acid to terminate the reaction, separating the mixture by cation exchange chromatography, washing and then freeze-drying to obtain antimicrobial peptide freeze-dried powder;

[0037] S3. Add hydroxyapatite, nano-microcrystalline cellulose and antimicrobial peptide into the modified silk fibroin solution and stir thoroughly to obtain the hydroxyapatite-based repair material.

[0038] A hydroxyapatite-based repair material is used in medical cosmetology. The repair material prepared in Example 1 to Example 3 is poured into a molding mold and freeze-dried at -60°C for 24 hours to obtain a repair sample. Before use, the sample is immersed in 90 v / v% methanol for 20 minutes, taken out and dried in a 37°C oven.

[0039] Comparative Example 1

[0040] A hydroxyapatite-based repair material, comprising the following components by weight: 22 parts of hydroxyapatite, 15 parts of nano-microcrystalline cellulose, 25 parts of silk fibroin, and 6 parts of antimicrobial peptide, wherein the modified silk fibroin is prepared by cross-linking and modifying the silk fibroin with polyethylene glycol glycidyl ether, and the antimicrobial peptide is LL-37 modified with polyethylene glycol. Hydroxyapatite is prepared by calcining stone animal bones, and the particle size is 20-50 μm.

[0041] The preparation method of the repair material comprises the following steps:

[0042] S1. Dissolve LL-37 in TRIS-HCl buffer solution, then add a certain proportion of monomethoxy polyethylene glycol succinimidyl propionate to the solution, the molar ratio of LL-37 to monomethoxy polyethylene glycol succinimidyl propionate is 1:6, react at room temperature for 30 minutes, add 1wt% trifluoroacetic acid to terminate the reaction, separate the mixture by cation exchange chromatography, wash and freeze-dry to obtain antimicrobial peptide freeze-dried powder;

[0043] S2. Add silk fibroin and antimicrobial peptide into TRIS-HCl buffer solution and stir thoroughly to dissolve, then add hydroxyapatite and nano-microcrystalline cellulose into the above solution and stir evenly to obtain the hydroxyapatite-based repair material.

[0044] Performance Testing

[0045] A biomaterial testing machine was used to perform mechanical tests. First, the repair materials prepared in Examples 1 to 3 and the comparative example were made into cylindrical specimens with a diameter of 15.6 mm and a height of 5 mm through a mold. The compressive stress and compression modulus were tested using a Bosch ElectroForce3220 high-precision biomaterial testing machine. The specimens were placed in the high-precision biomaterial testing machine, the test conditions were set, and then the test was performed. The test conditions were: the additional force value was 225N; the linear speed was 1mm / min, and the compression of the stent was half of the original height. Each sample was tested in parallel 3 times, and the results were averaged to obtain the data shown in Table 1 below. Compressive stress

[0046] Table 1 Mechanical properties test of hydroxyapatite-based repair materials

[0047]

[0048] As can be seen from Table 1, the mechanical properties and toughness of the biodegradable repair material prepared by the present invention are improved by compounding hydroxyapatite, nano-microcrystalline cellulose and modified silk fibroin and adding antimicrobial peptides as antibacterial substances.

[0049] The above contents are merely examples and explanations of the concept of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A hydroxyapatite-based repair material, characterized in that: The repair material comprises the following components in parts by weight: 15-25 parts of hydroxyapatite, 10-20 parts of nano-microcrystalline cellulose, 20-30 parts of modified silk fibroin, and 5-8 parts of antimicrobial peptide, wherein the modified silk fibroin is prepared by cross-linking and modifying the silk fibroin with polyethylene glycol glycidyl ether, and the antimicrobial peptide is LL-37 modified with polyethylene glycol; The preparation method of the repair material comprises the following steps: S1, mixing silk fibroin and polyethylene glycol glycidyl ether in a certain proportion and then standing at room temperature for 4 to 6 hours to obtain a modified silk fibroin solution; S2, dissolving LL-37 in a TRIS-HCl buffer solution, then adding a certain proportion of monomethoxy polyethylene glycol succinimidyl propionate to the solution, reacting at room temperature for 20 to 40 minutes, adding 1 wt % of trifluoroacetic acid to terminate the reaction, separating the mixture by cation exchange chromatography, washing and then freeze-drying to obtain an antimicrobial peptide freeze-dried powder; S3. Add hydroxyapatite, nano-microcrystalline cellulose and antimicrobial peptide into the modified silk fibroin solution and stir thoroughly to obtain the hydroxyapatite-based repair material.

2. The hydroxyapatite-based restorative material according to claim 1, characterized in that The hydroxyapatite is prepared by calcining animal bones and has a particle size of 20-50 μm.

3. The hydroxyapatite-based restorative material according to claim 1, characterized in that In the step S1, the molar ratio of silk fibroin to polyethylene glycol glycidyl ether is 5 to 10:

1.

4. The hydroxyapatite-based restorative material according to claim 1, characterized in that In the step S2, the molar ratio of LL-37 to monomethoxy polyethylene glycol succinimidyl propionate is 1:5-8.

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