A bone repair scaffold material, its preparation method and application

Abstract

This invention discloses a bone repair scaffold material, its preparation method, and its application. The preparation method includes the following steps: preparation of a mineralized collagen core spinning solution; adding mangiferin to a PLGA electrospinning solution and stirring to obtain a shell spinning solution; and using the core spinning solution and the shell spinning solution, obtaining the bone repair scaffold material through coaxial electrospinning. In this invention, PLGA and mangiferin together form the shell of the scaffold structure, and the sustained release of mangiferin provides a guarantee for the anti-inflammatory and angiogenic effects of the scaffold material. Simultaneously, it simulates the fibrous structure of the bone matrix, achieving slow degradation of the core and achieving the goal of long-term promotion of bone repair.

Description

Technical Field

[0001] This invention relates to the field of biomedical engineering technology, and in particular to a bone repair scaffold material, its preparation method, and its application. Background Technology

[0002] Repairing large-area bone defects caused by trauma, inflammation, or tumors is a hot topic in oral medicine research. While tissue engineering techniques involving the creation of seed cells—that is, extracting seed cells from the patient's own body, inoculating them onto a cellular scaffold, and then implanting them into the bone defect site—are effective treatments for bone defect repair, the seed cells can promote osteoogenesis in surrounding tissues as the scaffold degrades. However, in cases of large-area bone defects, insufficient blood supply and oxygen levels as low as 0%–3% in the defect area can lead to oxidative stress in cells, a sharp increase in reactive oxygen species, and increased cell apoptosis, ultimately resulting in treatment failure. Therefore, maintaining cell survival in large-area bone defect areas is receiving increasing attention from researchers.

[0003] Chinese patent CN 115120775 discloses a bone repair scaffold material, its preparation method, and its application. First, a core-spinning solution containing calcium phosphate oligomers and collagen is prepared, followed by a shell-spinning solution containing silk fibroin and VEGF. Finally, coaxial electrospinning is used to obtain composite coaxial electrospinned nanofibers with a shell-core structure. This method can enhance the bone repair process by promoting vascularization of nutrient supply, and can also leverage the osteogenic effect of calcium phosphate oligomers to promote bone defect repair. However, in cases of large-area bone defects, insufficient blood supply to the defect area, with oxygen content as low as 0%–3%, leads to oxidative stress in cells, a sharp increase in reactive oxygen species (ROS), and increased cell apoptosis, resulting in the failure of bone defect repair treatment. Although the angiogenic activity of VEGF plays a positive role in vascular remodeling in the early stages of bone tissue healing, it cannot effectively scavenge oxygen free radicals or maintain cell viability. Summary of the Invention

[0004] This invention provides a bone repair scaffold material, its preparation method, and its application. The aim is to address the limitations of existing mineralized adhesive raw materials, which cannot serve as inorganic components similar to natural bone to repair large-area bone defects. This invention utilizes the slow degradation ability of PLGA to extend the action time of mangiferin in the shell structure. Simultaneously, the shell structure degrades, while the core structure is exposed and begins to induce osteoblast mineralization. The organic polymers PLA and PLGA ensure that the material degradation rate is coordinated with the natural bone tissue regeneration rate, allowing anti-inflammatory, vascularization, and osteogenic processes to occur simultaneously. Ultimately, this solves the problem of oxidative stress in cells due to insufficient blood supply during large-area bone repair. Technical solution:

[0005] This invention provides a method for preparing a MAG-PLGA / MC bone repair scaffold material, comprising the following steps:

[0006] Step 1: Preparation of mineralized collagen core spinning solution

[0007] (1) Prepare a 0.1-1 mg / mL acid-soluble collagen solution from type I bovine collagen fibers;

[0008] (2) CaCl2·6H2O was added to the acid-soluble collagen solution to obtain Ca 2+ / Collagen complex solution;

[0009] (3) To the Ca 2+ Add PO4 to collagen complex solution 3- Aqueous solution was used to prepare Ca / P / collagen composite solution;

[0010] (4) Adjust the pH of the Ca / P / collagen complex solution to 8, stir for 8 to 24 hours to form a white suspension, and repeat the process of centrifugation-discarding the supernatant-resuspending in ultrapure water until the pH of the supernatant is between 7.0 and 7.5. Discard the supernatant to obtain the Ca / P / collagen mixture.

[0011] (5) The Ca / P / collagen mixture was pre-frozen at -30 to -20°C under normal pressure, and then freeze-dried under vacuum conditions.

[0012] (6) Grind the freeze-dried Ca / P / collagen mixture into mineralized collagen powder with a particle size of no more than 80 mesh;

[0013] (7) Add the mineralized collagen powder to the PLA electrospinning solution and stir for 1-3 hours to obtain the nuclear spinning solution;

[0014] Step 2: Add mangiferin to the PLGA electrospinning solution and stir for 1-3 hours to obtain the shell spinning solution;

[0015] Step 3: Using the aforementioned nuclear spinning solution and shell spinning solution, bone repair scaffold material is obtained through coaxial electrospinning.

[0016] Preferably, in step (2) of step one, Ca 2+ / Ca in collagen complex solution 2+ The molar mass ratio of collagen to collagen is 0.08–0.12 mol: 1 g.

[0017] Preferably, in step (3) of step one, the molar ratio of Ca to P in the Ca / P / collagen composite solution is 1.66. Preferably, in step (4) of step one, the centrifugal force is 8000-10000g.

[0018] Preferably, in step (7) of step one, the concentration of PLA by mass-volume ratio in the PLA electrospinning solution is 5%; the mass ratio of mineralized collagen dry powder to PLA is 1:1; and the solvent of the PLA electrospinning solution is chloroform.

[0019] Preferably, in step two, the concentration of the PLGA electrospinning solution by mass-volume ratio is 5%; the mass ratio of mangiferin to PLGA is 1:20; and the solvent of the PLGA electrospinning solution is hexafluoroisopropanol.

[0020] Preferably, in step three, the flow rate of the shell spinning solution is 25 μL / min, the flow rate of the core spinning solution is 20 μL / min, the voltage is 20 kV, the distance from the spinning nozzle to the receiving roller is 12 cm, the roller speed is 400 r / min, and the ambient temperature is 25 ± 2 °C.

[0021] Preferably, in step three, the volume ratio of the core spinning solution to the shell spinning solution is 1:1.

[0022] The second aspect of this invention provides a MAG-PLGA / MC bone repair scaffold material, which is prepared by the aforementioned preparation method. The MAG-PLGA / MC bone repair scaffold material is a composite coaxial electrospun nanofiber scaffold with a shell-core structure. The core is polylactic acid containing mineralized collagen, and the shell is polylactic-co-glycolic acid containing mangiferin.

[0023] The present invention also proposes the application of the MAG-PLGA / MC bone repair scaffold material prepared by the above preparation method as an orthopedic or dental repair material.

[0024] Beneficial effects:

[0025] The bone repair scaffold material provided by this invention possesses both burst drug release capability, which can rapidly increase the drug concentration in the target area, and sustained release capability, meeting the requirements for sustained-release scaffolds. This invention first prepares a core-spinning solution containing mineralized collagen, then prepares a shell-spinning solution containing mangiferin, and finally uses coaxial electrospinning to obtain composite coaxial electrospinned nanofibers with a shell-core structure. The core is mineralized collagen, and the shell is mangiferin. Mangiferin provides anti-inflammatory and pro-angiogenic capabilities during the repair of large-area bone defects. PLGA forms the shell of the scaffold structure, ensuring sustained release of mangiferin and achieving long-term vascularization. It allows for slow degradation of the core, achieving the goal of long-term bone repair promotion. In the case of large-area bone defects, it can effectively scavenge oxygen free radicals and maintain cell activity. The nanofiber structure obtained by coaxial electrospinning mimics the fibrous structure of the bone matrix, and its porosity meets the clinical requirements for bone repair scaffold materials, providing a scaffold structure for bone repair. The bone repair scaffold material prepared by this invention not only enhances the bone repair process by promoting vascularization of nutrient supply, but also leverages the better dispersibility of mineralized collagen in polymers to promote osteogenic processes and accelerate bone defect repair. The MAG-PLGA / nHAC extract exhibits good proliferative activity when co-cultured with cells and effectively promotes rapid spontaneous repair of bone defects, demonstrating excellent osteogenesis capabilities in vivo. It does not produce any cytotoxic effects during degradation, exhibiting good biocompatibility. The bone repair scaffold material prepared by this invention has significant application prospects in the field of bone tissue engineering. Attached Figure Description

[0026] Figure 1 This is a scanning electron microscope image of the mangiferin-polylactic acid-glycolic acid-mineralized collagen scaffold prepared in Example 1 of the present invention.

[0027] Figure 2 The porosity of the MAG-PLGA / nHAC scaffold prepared in Example 1 of this invention;

[0028] Figure 3 The cell proliferation curve of the MAG-PLGA / nHAC scaffold prepared in Example 1 of this invention is shown.

[0029] Figure 4 The image shows a CT image of the skull of a diabetic rat implanted with MAG-PLGA / MC prepared in Example 1 of this invention. Figure 5 The heart, liver, spleen, lungs, and kidneys of diabetic rats with skull defects were stained with H&E after implantation of the MAG-PLGA / nHAC scaffold material prepared in Example 1 of this invention. Specific Implementation

[0030] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0031] The preparation method of the present invention first prepares a polylactic acid (PLA) core spinning solution containing mineralized collagen, then prepares a polylactic acid-glycolic acid (PLGA) shell spinning solution containing mangiferin, and finally obtains a nanofiber scaffold with a shell-core structure using coaxial electrospinning technology.

[0032] Mangiferin is a small, bioactive monomer extracted from plants and widely available. Due to its high phenolic hydroxyl content, it effectively scavenge superoxide anions, hydrogen peroxide, and hydroxyl radicals, showing greater effectiveness in scavenging nitrogen radicals compared to existing natural polyphenols such as curcumin. Furthermore, the presence of two ortho-hydroxyl groups in its molecular structure gives it not only strong free radical scavenging ability but also a strong ability to chelate iron. It can bind with Fe... 3+ It forms stable complexes, reducing their reduction by ascorbic acid and effectively preventing ferric ions from being reduced to ferrous ions. In vitro studies have shown that mangiferin can protect deoxyribonucleotides, polyunsaturated fatty acids, phospholipids, erythrocyte membranes, various tissue (liver, brain) components, and proteins.

[0033] Mineralized collagen, a biomimetic bone material resembling the structure of natural bone tissue, is composed of biodegradable polylactic acid (PLA), osteoinductive nano-hydroxyapatite (nHA), and collagen. Collagen itself has osteoinductive properties. Through electrospinning, calcium and phosphorus minerals are fully deposited within the collagen network, in the voids, on the fiber surface, and between fibers, achieving both intrafiber and extrafiber mineralization. This results in a collagen / hydroxyapatite complex whose composition most closely resembles that of natural hard tissue, used for bone defect repair and promoting bone regeneration.

[0034] Mangiferin structural formula:

[0035]

[0036] Example 1

[0037] A method for preparing a MAG-PLGA / MC bone repair scaffold material includes the following steps:

[0038] Step 1: Preparation of mineralized collagen core spinning solution

[0039] (1) Add 1.14 ml of acetic acid to 200 ml of ultrapure water to prepare a 0.1 M acetic acid aqueous solution, and add 0.133 g of type I bovine collagen fiber to the 0.1 M acetic acid aqueous solution to prepare a 0.665 mg / mL acid-soluble collagen solution;

[0040] (2) 2.66 g of CaCl2·6H2O was added to the acid-soluble collagen solution to obtain Ca 2+ / Collagen complex solution, Ca 2+The molar mass ratio of collagen to collagen is 0.08–0.12 mol: 1 g;

[0041] (3) To Ca 2+ A Ca / P / collagen composite solution was prepared by adding 1.4 ml of H3PO4 to the collagen composite solution, with a Ca to P molar ratio of 1.66.

[0042] (4) Adjust the pH of the Ca / P / collagen composite solution to 8 using NaOH, stir for 8 to 24 hours to form a white suspension, centrifuge, discard the supernatant, and resuspend in ultrapure water. The centrifugal force is 8000 to 10000 g and the centrifugation time is 5 min. Repeat the centrifugation-discarding supernatant-resuspending process several times until the pH of the supernatant is between 7.0 and 7.5. Discard the supernatant to obtain the Ca / P / collagen mixture.

[0043] (5) The Ca / P / collagen mixture was pre-frozen at -30℃ for 4 hours under normal pressure, and then freeze-dried under vacuum for 48 hours.

[0044] (6) Grind the freeze-dried Ca / P / collagen mixture into mineralized collagen powder with a particle size of no more than 80 mesh;

[0045] (7) Dissolve 0.5g PLA in 10ml chloroform, add 0.5g mineralized collagen powder, stir for 1h to prepare nuclear spinning solution;

[0046] Step 2: Dissolve 0.5g PLGA in 10ml hexafluoroisopropanol, then add 0.025g MAG and stir for 1-3 hours to obtain shell spinning solution;

[0047] Step 3: Using the core spinning solution and shell spinning solution at a volume ratio of 1:1, coaxial electrospinning was performed to obtain the bone repair scaffold material. During electrospinning, the flow rate of the shell spinning solution was 25 μL / min, the flow rate of the core spinning solution was 20 μL / min, the voltage was 20 kV, the distance from the spinning nozzle to the receiving roller was 12 cm, the roller rotation speed was 400 rpm, and the ambient temperature was 25 °C. The MAG-PLGA / MC bone repair scaffold material was thus prepared.

[0048] Example 2

[0049] A method for preparing a MAG-PLGA / MC bone repair scaffold material includes the following steps:

[0050] Step 1: Preparation of mineralized collagen core spinning solution

[0051] (1) Add 1.14 ml of acetic acid to 200 ml of ultrapure water to prepare a 0.1 M acetic acid aqueous solution, and add 0.133 g of type I bovine collagen fiber to the 0.1 M acetic acid aqueous solution to prepare a 0.665 mg / mL acid-soluble collagen solution;

[0052] (2) CaCl2·6H2O was added to the acid-soluble collagen solution to obtain Ca 2+ / Collagen complex solution, Ca 2+ The ratio of collagen to collagen is 0.1 mol: 1 g;

[0053] (3) To Ca 2+ A Ca / P / collagen composite solution was prepared by adding H3PO4 to the collagen composite solution, with a Ca to P molar ratio of 1.66.

[0054] (4) Adjust the pH of the Ca / P / collagen composite solution to 8 using NaOH, stir for 24 hours to form a white suspension, centrifuge, discard the supernatant, and resuspend in ultrapure water at 10000 rpm for 5 min. Repeat the centrifugation-discarding of supernatant-resuspending in ultrapure water process several times until the pH of the supernatant is between 7.0 and 7.5. Discard the supernatant to obtain the Ca / P / collagen mixture;

[0055] (5) The Ca / P / collagen mixture was pre-frozen at -20℃ for 4 hours under normal pressure, and then freeze-dried under vacuum for 48 hours.

[0056] (6) Grind the freeze-dried Ca / P / collagen mixture into mineralized collagen powder with a particle size of no more than 80 mesh;

[0057] (7) Dissolve 1g PLA in 20ml chloroform, add 1g mineralized collagen powder, stir for 24h, and prepare nuclear spinning solution;

[0058] Step 2: Dissolve 1g PLGA in 20ml hexafluoroisopropanol, then add 0.05g MAG and stir for 24h to obtain shell spinning solution;

[0059] Step 3: Using the core spinning solution and shell spinning solution at a volume ratio of 1:1, coaxial electrospinning was performed to obtain the bone repair scaffold material. During electrospinning, the flow rate of the shell spinning solution was 25 μL / min, the flow rate of the core spinning solution was 20 μL / min, the voltage was 20 kV, the distance from the spinning nozzle to the receiving roller was 12 cm, the roller rotation speed was 400 rpm, and the ambient temperature was 25 °C. The MAG-PLGA / MC bone repair scaffold material was thus prepared.

[0060] Example 3

[0061] A method for preparing a MAG-PLGA / MC bone repair scaffold material includes the following steps:

[0062] Step 1: Preparation of mineralized collagen core spinning solution

[0063] (1) Add 1.14 ml of acetic acid to 200 ml of ultrapure water to prepare a 0.1 M acetic acid aqueous solution, and add 0.133 g of type I bovine collagen fiber to the 0.1 M acetic acid aqueous solution to prepare a 0.665 mg / mL acid-soluble collagen solution;

[0064] (2) 2.66 g of CaCl2·6H2O was added to the acid-soluble collagen solution to obtain Ca 2+ / Collagen complex solution; Ca 2+ The molar mass ratio of collagen to collagen is 0.12 mol: 1 g;

[0065] (3) To Ca 2+ A Ca / P / collagen composite solution was prepared by adding H3PO4 to the collagen composite solution, with a Ca to P molar ratio of 1.66.

[0066] (4) Adjust the pH of the Ca / P / collagen composite solution to 8 using NaOH, stir for 8 hours to form a white suspension, centrifuge, discard the supernatant, and resuspend in ultrapure water at 10000 rpm for 5 min. Repeat the centrifugation-discarding of supernatant-resuspending in ultrapure water process several times until the pH of the supernatant is between 7.0 and 7.5. Discard the supernatant to obtain the Ca / P / collagen mixture;

[0067] (5) The Ca / P / collagen mixture was pre-frozen at -25℃ for 4 hours under normal pressure, and then freeze-dried under vacuum for 48 hours.

[0068] (6) Grind the freeze-dried Ca / P / collagen mixture into mineralized collagen powder with a particle size of no more than 80 mesh;

[0069] (7) Dissolve 0.5g PLA in 10ml chloroform, add 0.5g mineralized collagen powder, stir for 24h to prepare nuclear spinning solution;

[0070] Step 2: Dissolve 0.5g PLGA in 10ml hexafluoroisopropanol, then add 0.025g MAG and stir for 24h to obtain shell spinning solution;

[0071] Step 3: Using the core spinning solution and shell spinning solution at a volume ratio of 1:1, coaxial electrospinning was performed to obtain the bone repair scaffold material. During electrospinning, the flow rate of the shell spinning solution was 25 μL / min, the flow rate of the core spinning solution was 20 μL / min, the voltage was 20 kV, the distance from the spinning nozzle to the receiving roller was 12 cm, the roller rotation speed was 400 rpm, and the ambient temperature was 25 °C. The MAG-PLGA / MC bone repair scaffold material was thus prepared.

[0072] The sample obtained in Example 1 was selected for relevant tests, and other examples have the same technical effects.

[0073] Images of the sample obtained in Example 1 observed by scanning electron microscopy are shown below. Figure 1 It has a high porosity, and the nano-calcium phosphate is distributed inside the collagen fibers. No minerals are visible on the surface in the scanning electron microscope images, indicating that the nano-calcium phosphate is mainly distributed inside the collagen.

[0074] Experiment 1: Measuring the porosity of the support material

[0075] The porosity of the scaffold material was measured using the wet-dry weight method. The scaffold material was immersed in anhydrous ethanol under vacuum conditions, assuming that the pores within the scaffold were fully replaced by the anhydrous ethanol. The porosity was then calculated using the following formula.

[0076]

[0077] In the formula, P: porosity; m1: initial weight of the scaffold (g); m2: final weight of the scaffold (g); ρ: density of anhydrous ethanol at room temperature (labeled as 0.789-0.791 g / cm³). 3 The default value is 0.79 g / cm³. 3 v: Support volume, 0.157cm 3 .

[0078] like Figure 2 As shown, the results indicate that the scaffold material has good porosity. The porosities of the nHAC, MAG-PLGA / nHAC, and MAG / nHAC groups are approximately 74.61% ± 2.15%, 73.31% ± 2.27%, and 74.06% ± 2.29%, respectively, which are consistent with the SEM results. Furthermore, neither of the two drug loading methods significantly affected the porosity of the scaffold material.

[0079] Experiment 2: Cell proliferation activity co-cultured with MAG-PLGA / nHAC extract

[0080] The material extract was prepared according to the International Organization for Standardization (ISO) standard 10993-5:2009. The porous nHAC scaffold and drug-loaded scaffold materials, sterilized with ethylene oxide, were used based on a material surface area: culture medium volume = 3 cm³. 2 The extract was added to a complete culture medium containing 1% dual antibiotic solution (100 μg / mL streptomycin and 100 U / mL penicillin) and 10% fetal bovine serum at a ratio of 1 / mL. The extract was then extracted at 37°C for 24 h. The pH value of the obtained extract was measured, and the extract was stored in a refrigerator at 4°C for later use.

[0081] Human bone marrow mesenchymal stem cells were divided into 1x10 groups.3 Cells were evenly seeded at a density of [number] cells / well in a 96-well plate. After incubation for 24 hours, 100 μL of material extraction buffer was used to replace the original culture medium. Simple cell culture was used as a negative control group, with three replicates per group. After 1, 3, and 5 days of culture, the culture medium in each well was aspirated, and 100 μL of serum-free culture medium was added, followed by 10 μL of CCK-8 solution. The plates were then incubated at 37°C for another 2 hours. Finally, the absorbance of each well was measured using a microplate reader at 450 nm. Figure 3 As shown in the cell proliferation curve, after 1, 3, and 5 days of culture, the absorbance of the MAG-PLGA / nHAC extract was higher than that of the cell culture group alone. The difference in absorbance on day 3 was statistically significant, indicating that the co-culture of cells with MAG-PLGA / nHAC extract has good proliferative activity.

[0082] Test 3 Repair and regeneration of the damaged area

[0083] A type 2 diabetes model was established in 4-week-old SD rats. Age-matched SD rats were fed routinely for 4 weeks and injected with an equal volume of STZ solvent as a control group. A 5 mm circular bone defect was created in the parietal bone of the rats, and a scaffold material was implanted to fill the defect area. Samples were collected at 4, 8, and 12 weeks after implantation. MicroCT was used for analysis to evaluate the repair and regeneration of the defect area. BV / TV and Tb.Th were calculated using an image analysis system as quantitative analysis indicators. Figure 4 As shown, the results indicate that this scaffold material has a good ability to promote osteogenesis in vivo. At 4, 8, and 12 weeks postoperatively, the three-dimensional reconstructed images showed that the MAG-PLGA / nHAC scaffold exhibited slightly more bone regeneration compared to the nHAC scaffold alone. Statistical analysis of bone volume fraction (BV / TV) and trabecular bone thickness (Tb.Th) showed trends that were basically consistent with those of the three-dimensional reconstructed images.

[0084] Test 4 Cytotoxicity Test

[0085] Rats implanted with the material of this invention and healthy rats were selected, and visceral sections of the heart, liver, spleen, lungs and kidneys of the rats were observed. Figure 5 It was observed that the heart, liver, spleen, lungs, and kidneys of the rats showed no obvious abnormalities, and their tissue characteristics were not significantly different from those of the visceral sections of healthy rats. This further demonstrates that the MAG-PLGA / nHAC scaffold material prepared in Example 1 of this invention has low toxicity to the body, does not produce any cytotoxic effects during degradation, and has good biosafety.

[0086] In summary, the MAG-PLGA / MC bone repair scaffold material prepared by this invention is a composite coaxial electrospun nanofiber scaffold with a shell-core structure. The core is polylactic acid containing mineralized collagen, and the shell is polylactic-co-glycolic acid containing mangiferin. The porosity of the MAG-PLGA / MC bone repair scaffold material meets the clinical requirements for bone repair scaffold materials. The MAG-PLGA / nHAC extract exhibits good proliferative activity when co-cultured with cells and can effectively promote rapid spontaneous repair of bone defects, demonstrating a strong ability to promote osteoogenesis in vivo. It does not produce any cytotoxic effects during degradation, exhibiting good biocompatibility. The MAG-PLGA / MC bone repair scaffold prepared by the method of this invention has great application potential in the repair of large-area bone defects caused by trauma, inflammation, and tumors.

Claims

1. A method for preparing a MAG-PLGA / MC bone repair scaffold material, characterized in that, Includes the following steps: Step 1: Preparation of mineralized collagen core spinning solution (1) Prepare a 0.1-1 mg / mL acid-soluble collagen solution from type I bovine collagen fibers; (2) CaCl2-6H2O was added to the acid sol collagen solution, thereby preparing a Ca 2+ / collagen composite solution; (3) adding PO4 2+ containing solution to the Ca 3- collagen composite solution; and aqueous solution, thereby preparing a Ca / P / collagen composite solution; (4) Adjust the pH of the Ca / P / collagen complex solution to 8, stir for 8 to 24 hours to form a white suspension, and repeat the process of centrifugation-discarding the supernatant-resuspending in ultrapure water until the pH of the supernatant is between 7.0 and 7.

5. Discard the supernatant to obtain the Ca / P / collagen mixture. (5) The Ca / P / collagen mixture was pre-frozen at -30 to -20°C under normal pressure, and then freeze-dried under vacuum conditions. (6) Grind the freeze-dried Ca / P / collagen mixture into mineralized collagen powder with a particle size of no more than 80 mesh; (7) Add the mineralized collagen powder to the PLA electrospinning solution and stir for 1-3 hours to obtain the nuclear spinning solution; Step 2: Add mangiferin to the PLGA electrospinning solution and stir for 1-3 hours to obtain the shell spinning solution; Step 3: Using the aforementioned nuclear spinning solution and shell spinning solution, bone repair scaffold material is obtained through coaxial electrospinning.

2. The preparation method according to claim 1, characterized in that, In step (2) of step one, Ca 2+ / Ca in collagen complex solution 2+ The molar mass ratio of collagen to collagen is 0.08–0.12 mol: 1 g.

3. The preparation method according to claim 1, characterized in that, In step (3) of step one, the molar ratio of Ca to P in the Ca / P / collagen composite solution is 1.

66.

4. The preparation method according to claim 1, characterized in that, The centrifugal force in step (4) of step one is 8000-10000g.

5. The preparation method according to claim 1, characterized in that, In step (7) of step one, the concentration of PLA by mass-volume ratio in the PLA electrospinning solution is 5%; the mass ratio of mineralized collagen dry powder to PLA is 1:1; and the solvent of the PLA electrospinning solution is chloroform.

6. The preparation method according to claim 1, characterized in that, In step two, the concentration of the PLGA electrospinning solution by mass-volume ratio is 5%; the mass ratio of mangiferin to PLGA is 1:20; and the solvent of the PLGA electrospinning solution is hexafluoroisopropanol.

7. The preparation method according to claim 1, characterized in that, In step three, the flow rate of the shell spinning solution during electrospinning is 25 μL / min, the flow rate of the core spinning solution is 20 μL / min, the voltage is 20 kV, the distance from the spinning nozzle to the receiving roller is 12 cm, the roller speed is 400 r / min, and the ambient temperature is 25 ± 2 °C.

8. The preparation method according to claim 1, characterized in that, In step three, the volume ratio of the core spinning solution to the shell spinning solution is 1:

1.

9. A MAG-PLGA / MC bone repair scaffold material, characterized in that: The MAG-PLGA / MC bone repair scaffold material is prepared by the preparation method according to any one of claims 1 to 8. The MAG-PLGA / MC bone repair scaffold material is a composite coaxial electrospun nanofiber scaffold with a shell-core structure. The core is polylactic acid containing mineralized collagen, and the shell is polylactic-co-glycolic acid containing mangiferin.

10. The use of a MAG-PLGA / MC bone repair scaffold material prepared by the preparation method according to any one of claims 1 to 8 as an orthopedic or dental repair material.

Images