A bone repair material and a preparation method and application thereof

Abstract

The embodiment of the application discloses a kind of bone repair materials and its preparation method and application.The preparation method includes: poly-L-lactic acid and barium titanate are added in hexafluoroisopropanol, fully stir, obtain PLLA / BTO suspension;Poly-L-lactic acid is dissolved in hexafluoroisopropanol, then add catalpol, obtain PLLA / CA solution;With the PLLA / BTO suspension as shell material, PLLA / CA solution as core material, coaxial electrospinning is carried out, to obtain composite nanomaterial, then remove solvent, obtain the bone repair material.The bone repair material of the application not only has higher anti-osteoporosis activity, but also can improve the stability of the material (low degradation rate, long complete degradation time) and enhance the piezoelectric effect, achieve excellent osteoporosis bone defect repair effect;Preparation process is relatively simple and convenient, key technology is easy to control, and manufacturing cost is lower.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of bone repair technology, and specifically to a bone repair material and a preparation method and application thereof. Background Art

[0002] The increase in the number of osteoporosis patients has led to an increase in the incidence of diseases such as fractures, and often makes bones difficult to heal. Clinically, various reasons such as severe trauma or surgery usually cause large bone defects, which cannot heal on their own. The current treatment methods for large bone defects in osteoporosis patients have certain limitations. For example, autologous bone repair materials, which are the gold standard for bone defect repair, have shortcomings such as insufficient anti-osteoporosis activity, donor site pain and local complications, and limited quantity. The current clinical application of autologous bone repair materials to treat this type of disease is still limited. In order to solve the above problems, the development of bone repair materials with anti-osteoporosis activity is one of the means to solve this difficult problem.

[0003] In recent years, the emergence of bone tissue engineering technology has greatly improved the efficiency of bone healing and provided a new direction for the treatment of bone defects. Tissue engineering technology includes three major elements: seed cells, active factors and active scaffolds. In terms of seed cells, they include chondrocytes, osteoblasts, bone marrow mesenchymal stem cells, adipose mesenchymal stem cells, etc. In terms of active factors, TGF-β3, BMP-7, Sr 2+ , IL-4, FGF-18, and PTH have been explored for use in bone tissue engineering. Regarding active scaffolds, several polymers with piezoelectric properties, such as PCL, PLLA, and PVDF, as well as natural polymers such as silk fibroin, fibrin, collagen, gelatin, and sodium alginate, have been explored for bone tissue engineering. Because bone inherently possesses piezoelectric properties, piezoelectric materials can mimic the bone microenvironment, promoting osteogenesis and healing, making them a promising material for bone repair. Furthermore, good biocompatibility provides a suitable microenvironment for seed cell growth, facilitating cell adhesion, proliferation, and differentiation. Appropriate mechanical strength provides excellent mechanical support, maintaining the original morphological integrity of the tissue. Long-lasting stimulation with drugs or growth factors also plays a crucial role in bone repair, accelerating bone healing and making them particularly suitable for patients with osteoporosis. In summary, scaffolds with piezoelectric properties, self-generation, good biocompatibility, excellent mechanical strength, and the ability to carry drugs or growth factors hold promise for bone repair, particularly for patients with osteoporotic bone defects. Summary of the Invention

[0004] The present invention is made based on the following knowledge of the inventors:

[0005] In terms of material selection, organic piezoelectric materials such as PLLA have good biocompatibility and excellent piezoelectric properties, are easily degradable, and are non-toxic, but they suffer from insufficient mechanical strength. Inorganic piezoelectric materials such as BaTiO3 (BTO) possess strong piezoelectricity and mechanical properties, but are somewhat toxic and non-degradable. The research proposal of adding an appropriate amount of inorganic piezoelectric material BTO to the organic piezoelectric material PLLA to construct a composite piezoelectric material can retain the advantages of each of these two piezoelectric materials, forming a complementary advantage while addressing the shortcomings of each, making it a worthwhile experimental concept to try.

[0006] In terms of drug selection, Rehmannia glutinosa is a traditional Chinese medicine for osteoporosis, which has the effects of "nourishing yin and blood, replenishing essence and filling marrow" to prevent and treat osteoporosis. According to the 2020 edition of the Chinese Pharmacopoeia, catalpol (CA) and verbascoside are used as indicator components to qualitatively identify Rehmannia glutinosa, and catalpol and rehmannia glutinosa glycoside D are also used as components for the content determination of Rehmannia glutinosa. Catalpol is a cyclopentane ether terpene glycoside compound with antioxidant and anti-inflammatory activities. In bone loss or osteoporosis models such as bone defect induction, ovariectomy, streptozotocin induction, nicotine induction and lipopolysaccharide induction in female or male rats or mice, catalpol has been reported to have anti-osteoporosis effects by promoting osteogenesis and inhibiting osteoclasts.

[0007] To this end, an embodiment of the present invention provides a bone repair material and a preparation method and application thereof.

[0008] In order to achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0009] According to a first aspect of an embodiment of the present invention, the present invention provides a method for preparing a bone repair material, comprising:

[0010] Poly (L-lactic acid) and barium titanate were added to hexafluoroisopropanol and stirred thoroughly to obtain a PLLA / BTO suspension;

[0011] Poly (L-lactic acid) was dissolved in hexafluoroisopropanol, and then catalpol was added to obtain a PLLA / CA solution;

[0012] The PLLA / BTO suspension is used as the shell material and the PLLA / CA solution is used as the core material to perform coaxial electrospinning to obtain a composite nanomaterial, and then the solvent is removed to obtain the bone repair material.

[0013] Furthermore, in the PLLA / BTO suspension, the mass percentage of poly (L-lactic acid) is 10-20%, and the mass percentage of barium titanate is 0.5-4%.

[0014] Furthermore, in the PLLA / CA solution, the mass percentage of poly-L-lactic acid is 10-20%, and the mass percentage of catalpol is 0.1-0.6%.

[0015] Furthermore, the parameters of the coaxial electrospinning include:

[0016] The injection speed of the PLLA / BTO suspension is 0.2-1 mm / min;

[0017] The spraying speed of the PLLA / CA solution is 0.1-0.5 mm / min;

[0018] The spinning voltage is 10-15 kV and the receiving distance is 11-15 cm;

[0019] The needle of the shell material syringe has an inner diameter of 0.5-1.0 mm and an outer diameter of 1.0-1.5 mm;

[0020] The inner diameter of the needle of the nuclear layer material syringe is 0.1-0.5 mm, and the outer diameter is 0.5-1.0 mm.

[0021] Furthermore, the specific operation of removing the solvent is: placing the composite nanomaterial in a vacuum drying oven and drying it at 80-120 Pa and 20-28° C. for 2-4 hours.

[0022] Furthermore, the nanofiber diameter of the bone repair material is 130-230 nm.

[0023] According to a second aspect of the embodiments of the present invention, the present invention provides a bone repair material, which is made by any of the methods described above.

[0024] According to a third aspect of the embodiments of the present invention, the present invention provides use of the bone repair material as described above in treating osteoporotic bone defects.

[0025] The embodiments of the present invention have the following advantages:

[0026] 1. The bone repair material of the present invention uses specific amounts of PLLA and BTO, which have the characteristics of high safety, strong piezoelectricity and excellent mechanical properties. A specific amount of catalpol, an active ingredient of the traditional Chinese medicine Rehmannia glutinosa, plays an auxiliary therapeutic role. It not only has high anti-osteoporosis activity, but also improves the stability of the material (low degradation rate, long complete degradation time) and enhances the piezoelectric effect, achieving excellent osteoporotic bone defect repair effect.

[0027] 2. The preparation process of the bone repair material of the present invention is relatively simple and convenient, the key technology is easy to control, and the production cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other implementation drawings based on the provided drawings without inventive effort.

[0029] Figure 1 A schematic diagram of the preparation process of the bone repair material provided by the present invention;

[0030] Figure 2 This is a scanning electron microscope image of the bone repair material provided by the present invention;

[0031] Figure 3 An electrometer measures voltage and current for the bone repair material provided by the present invention;

[0032] Figure 4 This is the degradation rate curve of the bone repair material provided by the present invention;

[0033] Figure 5 The cytotoxicity test results of the bone repair material provided by the present invention;

[0034] Figure 6 HE staining results of the bone defect repair activity of the bone repair material provided by the present invention;

[0035] Figure 7 The bone defect repair activity scoring result of the bone repair material provided by the present invention;

[0036] Figure 8 The osteocalcin staining results of the pathological sections provided by the present invention;

[0037] Figure 9 The bone volume fraction BV / TV of the micro-CT provided by the present invention;

[0038] Figure 10 This is a physical picture of the bone repair material provided by the present invention. DETAILED DESCRIPTION

[0039] The following describes the implementation of the present invention using specific embodiments. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. Obviously, the embodiments described are only a portion of the present invention, not all of it. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0040] Example 1

[0041] This embodiment provides a method for preparing a bone repair material, comprising the following steps:

[0042] (1) Preparation of shell materials

[0043] 5 g of poly (L-lactic acid) (PLLA) and 0.5 g of barium titanate (BTO) were added to 44.5 g of hexafluoroisopropanol (HFIP) and stirred for 12 h to obtain a PLLA / BTO suspension, which was loaded into injector B as the shell material for coaxial electrospinning.

[0044] (2) Preparation of core layer materials

[0045] 5 g of PLLA was added to 44.95 g of HFIP and stirred thoroughly for 12 h. 50 mg of catalpol (CA) was added and stirred evenly to obtain a PLLA / CA solution, which was loaded into syringe A as the core layer material for coaxial electrospinning.

[0046] (3) Preparation of bone repair materials

[0047] Coaxial electrospinning was used with the following parameters: the PLLA / BTO suspension was ejected at a velocity of 0.2 mm / min; the PLLA / CA solution was ejected at a velocity of 0.1 mm / min; the spinning voltage was 10 kV, the receiving distance was 11 cm; the needle of the shell material syringe had an inner diameter of 0.9 mm and an outer diameter of 1.2 mm; the needle of the core material syringe had an inner diameter of 0.2 mm and an outer diameter of 0.6 mm. The sample was then dried in a vacuum oven at 100 Pa and 20°C for 2 hours to obtain the bone repair material.

[0048] Example 2

[0049] This embodiment provides a method for preparing a bone repair material, comprising the following steps:

[0050] (1) Preparation of shell materials

[0051] 7.5 g of poly (L-lactic acid) (PLLA) and 1.0 g of barium titanate (BTO) were added to 41.5 g of hexafluoroisopropanol (HFIP) and stirred for 12 h to obtain a PLLA / BTO suspension, which was loaded into injector B as the shell material for coaxial electrospinning.

[0052] (2) Preparation of core layer materials

[0053] 7.5 g of PLLA was added to 42.375 g of HFIP and stirred thoroughly for 12 h. 125 mg of catalpol (CA) was added and stirred evenly to obtain a PLLA / CA solution, which was loaded into syringe A as the core layer material for coaxial electrospinning.

[0054] (3) Preparation of bone repair materials

[0055] Coaxial electrospinning was used with the following parameters: the PLLA / BTO suspension was ejected at a velocity of 0.5 mm / min; the PLLA / CA solution was ejected at a velocity of 0.3 mm / min; the spinning voltage was 13 kV, and the receiving distance was 13 cm. The needle of the shell material syringe had an inner diameter of 0.9 mm and an outer diameter of 1.2 mm; the needle of the core material syringe had an inner diameter of 0.2 mm and an outer diameter of 0.6 mm. The sample was then dried in a vacuum oven at 100 Pa and 20°C for 3 hours to obtain the bone repair material.

[0056] Example 3

[0057] This embodiment provides a method for preparing a bone repair material, comprising the following steps:

[0058] (1) Preparation of shell materials

[0059] 10 g of poly (L-lactic acid) (PLLA) and 2 g of barium titanate (BTO) were added to 38 g of hexafluoroisopropanol (HFIP) and stirred for 12 h to obtain a PLLA / BTO suspension, which was loaded into injector B as the shell material for coaxial electrospinning.

[0060] (2) Preparation of core layer materials

[0061] 10 g of PLLA was added to 39.749 g of HFIP and stirred thoroughly for 12 h. 251 mg of catalpol (CA) was added and stirred evenly to obtain a PLLA / CA solution, which was loaded into syringe A as the core layer material for coaxial electrospinning.

[0062] (3) Preparation of bone repair materials

[0063] Coaxial electrospinning was used with the following parameters: the PLLA / BTO suspension was ejected at a velocity of 1 mm / min; the PLLA / CA solution was ejected at a velocity of 0.5 mm / min; the spinning voltage was 15 kV, and the receiving distance was 15 cm. The needle of the shell material syringe had an inner diameter of 0.9 mm and an outer diameter of 1.2 mm; the needle of the core material syringe had an inner diameter of 0.2 mm and an outer diameter of 0.6 mm. The sample was then dried in a vacuum oven at 100 Pa and 20°C for 3 hours to obtain the bone repair material.

[0064] Comparative Example 1

[0065] This comparative example provides a method for preparing a bone repair material:

[0066] (1) Preparation of shell materials

[0067] 5 g of poly (L-lactic acid) (PLLA) and 0.5 g of barium titanate (BTO) were added to 44.5 g of hexafluoroisopropanol (HFIP) and stirred for 12 h to obtain a PLLA / BTO suspension, which was loaded into injector B as the shell material for coaxial electrospinning.

[0068] (2) Preparation of core layer materials

[0069] 5 g of PLLA was added to 44.97 g of HFIP and stirred thoroughly for 12 h. 30 mg of catalpol (CA) was added and stirred evenly to obtain a PLLA / CA solution, which was loaded into syringe A as the core layer material for coaxial electrospinning.

[0070] (3) Preparation of bone repair materials

[0071] Coaxial electrospinning was used with the following parameters: the PLLA / BTO suspension was ejected at a velocity of 0.2 mm / min; the PLLA / CA solution was ejected at a velocity of 0.1 mm / min; the spinning voltage was 10 kV, the receiving distance was 11 cm; the needle of the shell material syringe had an inner diameter of 0.9 mm and an outer diameter of 1.2 mm; the needle of the core material syringe had an inner diameter of 0.2 mm and an outer diameter of 0.6 mm. The sample was then dried in a vacuum oven at 100 Pa and 20°C for 2 hours to obtain the bone repair material.

[0072] Comparative Example 2

[0073] This comparative example provides a method for preparing a bone repair material:

[0074] (1) Preparation of shell materials

[0075] 10 g of poly (L-lactic acid) (PLLA) and 2 g of barium titanate (BTO) were added to 38 g of hexafluoroisopropanol (HFIP) and stirred for 12 h to obtain a PLLA / BTO suspension, which was loaded into injector B as the shell material for coaxial electrospinning.

[0076] (2) Preparation of core layer materials

[0077] 10 g of PLLA was added to 39.65 g of HFIP and stirred thoroughly for 12 h. 350 mg of catalpol (CA) was added and stirred evenly to obtain a PLLA / CA solution, which was loaded into syringe A as the core layer material for coaxial electrospinning.

[0078] (3) Preparation of bone repair materials

[0079] Coaxial electrospinning was used with the following parameters: the PLLA / BTO suspension was ejected at a velocity of 1 mm / min; the PLLA / CA solution was ejected at a velocity of 0.5 mm / min; the spinning voltage was 15 kV, and the receiving distance was 15 cm. The needle of the shell material syringe had an inner diameter of 0.9 mm and an outer diameter of 1.2 mm; the needle of the core material syringe had an inner diameter of 0.2 mm and an outer diameter of 0.6 mm. The sample was dried in a vacuum oven at 20°C for 3 hours to obtain the bone repair material.

[0080] Comparative Example 3

[0081] This comparative example uses autologous bone, and during the experiment, the autologous skull was obtained for autologous bone transplantation repair to observe the osteoinductive activity and bone repair effect. Specifically, the autologous bone used in Test Example 3 was derived from the skull of the same young mouse.

[0082] Test Example 1

[0083] Performance Testing

[0084] Scanning electron microscopy: The bone repair materials of Examples 1-3 and Comparative Examples 1-2 were taken out of their sealed packaging, and 5 mm × 5 mm samples were cut with microscissors. Conductive adhesive was applied and gold was evaporated in a gold evaporation chamber. Scanning electron microscopy was then performed under conditions of a high voltage of 5000 V and an emission current of 10 μA. The samples were observed and photographed. Figure 2 As shown, the fiber diameter of the bone repair material of Example 1 is 156±24 nm; the fiber diameter of the bone repair material of Example 2 is 146±22 nm; the fiber diameter of the bone repair material of Example 3 is 142±23 nm; the fiber diameter of the bone repair material of Comparative Example 1 is 256±24 nm; and the fiber diameter of the bone repair material of Comparative Example 2 is 108±16 nm.

[0085] Piezoelectric performance: At room temperature, the bone repair materials (5 mm × 5 mm) of Examples 1-3 and Comparative Examples 1-2 were placed between two metal plates and tested at 100 kV / mm. -1 The surface charge was released after polarization for 15 minutes under an electric field of 100 nm and then left for 24 hours. The voltage and current were measured using a commercial D33 meter using a quasi-static method. All the above measurements were performed at room temperature. Figure 3 As shown, there is no significant difference in voltage between the bone repair materials of Examples 1-3 and Comparative Examples 1-2, and there is no significant difference in current between the bone repair materials of Examples 1-3 and Comparative Example 2, but both are significantly higher than Comparative Example 1. The results show that both Examples 1-3 and Comparative Example 2 have excellent piezoelectric properties.

[0086] Degradation performance: The bone repair materials of Examples 1-3 and Comparative Examples 1-2 were placed in a centrifuge tube and a certain amount of simulated body fluid (MG6615) was added at a volume ratio of 1:20. The simulated body fluid was replaced every two days. The samples were filtered, washed, dried, and weighed at 0, 1, 2, 3, 4, 6, and 8 weeks, and the degradation rate (%) was calculated as [1-(mass after immersion / mass before immersion)] × 100%. The results are shown in Figure 2. Figure 4 As shown, over the same time period, the degradation rates of the bone repair materials in Examples 1-3 were significantly lower than those in Comparative Examples 1-2. The degradation rates of the bone repair materials in Examples 1-3 and Comparative Example 2 reached 100% at 10 weeks, extending the degradation time by 2 weeks compared to Comparative Example 1. These results demonstrate that the bone repair materials provided by the present invention have excellent stability, low degradation rates, and prolonged degradation times, and can better meet the needs of in vivo repair therapy.

[0087] Test Example 2

[0088] Detection of cell activity: MC3T3-E1 osteoblasts were used as in vitro experimental research subjects. α-MEM culture medium containing 10% fetal bovine serum was added and cultured in a 37°C, 5% CO2 incubator. When the cells grew to 80% confluence, they were digested and passaged with 0.25% trypsin. The bone repair material discs (14 mm in diameter) of Examples 1-3 and Comparative Examples 1-2 were placed in 24-well culture plates, sterilized with 60Co irradiation, and then incubated in culture medium for 24 hours. 1×10 4 Cells were plated in 3 wells per group. No material was placed in the blank control group. After 3 days of culture in the incubator, the culture plates were removed and cell proliferation activity was assessed using the CCK-8 assay. The original culture medium was discarded, and 100 μl of fresh culture medium was added to each well, followed by 10 μl of CCK-8 solution. The cells were cultured in the incubator for 4 hours. The absorbance was measured at 450 nm, and the cell proliferation rate was calculated.

[0089] The results are as follows Figure 5 As shown, the cell activities of the bone repair materials of Examples 1-3 were significantly higher than those of Comparative Examples 1 and 2.

[0090] Test Example 3

[0091] Osteoporosis bone defect repair test: 40 adult male SD rats weighing about 300g were selected and randomly divided into experimental groups 1-3 and control groups 2-3, with 8 rats in each group. First, an osteoporosis model was induced by intraperitoneal injection of dexamethasone solution. After the model was successfully established, the rats were anesthetized by intraperitoneal injection of 3% sodium pentobarbital, placed in a prone position, and the skin of the skull was prepared and disinfected with iodine. An incision of about 2 cm was made on the midline of the skull to separate the periosteum. A 5mm diameter defect was made on each side of the sagittal suture using a bone trephine. The materials of Examples 1-3 and Comparative Examples 2-3 were implanted into the defects of each group of mice, and the periosteum and skin were sutured. After surgery, 80,000 units of penicillin were injected intramuscularly for 3 consecutive days, and the mice were kept in a conventional manner. Strict aseptic operation was performed during the operation, and all defects were completed by the same group of personnel. After surgery, the animals were observed for adverse reactions such as swelling, redness, and exudation at the wound. Eight weeks after surgery, HE staining and osteocalcin immunohistochemical staining were used to observe the osteogenesis, and micro-CT was used to measure the bone volume fraction (BV / TV) to evaluate the bone defect repair effect.

[0092] HE staining: Fix with 4% paraformaldehyde, dehydrate, embed, slice, etc. to make specimen slices. HE staining is used to observe the histological reaction and evaluate the bone induction score. The histological scoring standard proposed by Nilsson is used. Semi-quantitative analysis of the results of each group of scaffold materials was performed by an experimenter who was not aware of the experimental groups. The results are shown in the figure below. Figure 6 and Figure 7 As shown, the bone repair effects of test groups 1-3 were significantly better than those of control example 2, and close to those of control group 3, indicating that the bone defect repair activity of the bone repair materials of Examples 1-3 was significantly better than that of control example 2, and close to that of autologous bone.

[0093] Immunohistochemistry: Immunohistochemistry was used to detect changes in osteocalcin expression. Briefly, tissue samples were fixed with 4% paraformaldehyde, embedded and sliced, paraffin sections were dewaxed to water, incubated with 3% hydrogen peroxide at room temperature, rinsed with distilled water and then soaked in PBS twice for 5 minutes each time, blocked, and incubated overnight with the addition of primary antibody working solution. After washing, the secondary antibody working solution was added and incubated for 30 minutes, washed again, and rinsed with a color developer, counterstained, dehydrated, transparent, sealed, and observed. The results are shown in Figure 2. Figure 8 As shown, the osteocalcin staining results of the pathological sections showed that the osteogenesis effects of Examples 1-3 were significantly better than those of Comparative Example 2, and were slightly worse or equivalent to those of Comparative Example 3.

[0094] Micro-CT detection: Micro-CT (Inveon MM CT) was used to scan the skulls of mice in each group, and the bone volume fraction (BV / TV) was quantitatively analyzed to evaluate the bone defect repair effect. The scanning parameters were: voltage 80kV, current 500μA, scanning software selected Inveon Acquisition Workplace, and quantitative analysis was performed using Inveon Research Workplace analysis software. The selected region of interest range was: diameter 5mm, depth 4-7mm. The results are shown in Figure 9. The micro-CT bone volume fraction (BV / TV) results showed that the new bone ratio of Comparative Example 3 was about 50%, the new bone ratio of Comparative Example 2 was about 30%, and the new bone ratio of Examples 1-3 was about 40%. This shows that the repair effect of the bone repair materials of Examples 1-3 is significantly better than that of Comparative Example 2, and second only to autologous bone.

[0095] Although the present invention has been described in detail above using general descriptions and specific embodiments, it will be apparent to those skilled in the art that modifications and improvements may be made thereto. Therefore, such modifications and improvements, without departing from the spirit of the present invention, are intended to be within the scope of protection claimed herein.

Claims

1. A method for preparing a bone repair material, characterized in that: include: Poly (L-lactic acid) and barium titanate were added to hexafluoroisopropanol and stirred thoroughly to obtain a PLLA / BTO suspension; Poly (L-lactic acid) was dissolved in hexafluoroisopropanol, and then catalpol was added to obtain a PLLA / CA solution; The PLLA / BTO suspension is used as the shell material and the PLLA / CA solution is used as the core material to perform coaxial electrospinning to obtain a composite nanomaterial, and then the solvent is removed to obtain the bone repair material; In the PLLA / BTO suspension, the mass percentage of poly-L-lactic acid is 10-20%, and the mass percentage of barium titanate is 0.5-4%; In the PLLA / CA solution, the mass percentage of poly-L-lactic acid is 10-20%, and the mass percentage of catalpol is 0.1-0.6%; The parameters of the coaxial electrospinning include: The injection speed of the PLLA / BTO suspension is 0.2-1 mm / min; The spraying speed of the PLLA / CA solution is 0.1-0.5 mm / min; The spinning voltage is 10-15 kV and the receiving distance is 11-15 cm; The needle of the shell material syringe has an inner diameter of 0.5-1.0 mm and an outer diameter of 1.0-1.5 mm; The needle of the nuclear layer material syringe has an inner diameter of 0.1-0.5 mm and an outer diameter of 0.5-1.0 mm.

2. The method for preparing the bone repair material according to claim 1, characterized in that: The specific operation of removing the solvent is: placing the composite nanomaterial in a vacuum drying oven and drying it at 80-120 Pa and 20-28° C. for 2-4 hours.

3. The method for preparing the bone repair material according to claim 1, wherein: The diameter of the nanofibers of the bone repair material is 130-230 nm.

4. A bone repair material, characterized in that: The invention is prepared by the method according to any one of claims 1 to 3.

5. Use of the bone repair material according to claim 4 in medicine for treating osteoporosis and bone defects.

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