CN111603607A - A kind of silk fibroin-calcium hydrogen phosphate complex obtained by using silk fibroin as template and preparation method thereof - Google Patents

Abstract

The present invention relates to a silk fibroin-calcium hydrogen phosphate complex obtained by induction using silk fibroin as a template and a preparation method thereof. The multi-layer mineral structure formed by the growth of the single-layer regular comb-shaped crystals arranged in close order or the plate-like structure obtained by further encapsulation of the multi-layer mineral structure, the silk fibroin is uniformly distributed in the composite. The silk fibroin-calcium hydrogen phosphate complex provided by the present invention has high strength and good biocompatibility, and the multi-level structure of silk fibroin-induced synthetic mineralization provides a new idea for more economical and effective biomimetic synthesis, And it can provide better materials and methods for bone regeneration and bone tissue repair.

Description

A kind of silk fibroin-calcium hydrogen phosphate complex obtained by using silk fibroin as a template and its preparation preparation method

technical field

The invention belongs to the technical field of medical materials, and in particular relates to a silk fibroin-calcium hydrogen phosphate complex obtained by induction with silk fibroin as a template and a preparation method thereof.

Background technique

Organisms in nature can synthesize organic-inorganic composites with complex structures by themselves. Usually, the obtained biomaterials have some excellent properties due to their special composition. Inspired by the mineral structure in nature, the artificial preparation of organic-inorganic hybrid materials with corresponding structures has attracted the attention of scientists from all over the world. Among them, the excellent mechanical properties of vertebrate bones are particularly closely related to their composition and structure. Bone tissue is a typical organic-inorganic complex with a multi-level structure from micro to macro. It contains about 34% of the organic matrix with collagen as the main component, and the rest is mostly inorganic in the state of apatite. In order to meet the strength and toughness requirements of bones in different parts of the body, the two are combined in different proportions and ways to form a hierarchical structure of bones. Inspired by the mineralization process in vivo, the ingenious combination of organic polymers and inorganic materials to obtain composite materials with specific morphological structures and excellent properties is of great significance for the artificial design and preparation of multifunctional composite materials.

At this stage, many studies have focused on modeling the structure and formation of bone, and the most concerned is the use of collagen with the same composition as natural bone as an organic matrix for mineralization. Silk protein has a hierarchical structure similar to that of collagen, and at the same time has the advantages of excellent mechanical properties, low degradation, good biocompatibility and low immunogenicity. Therefore, it is often used as a raw material in the research of bone tissue materials. At present, the biomimetic composite materials prepared with silk fibroin as the organic matrix and calcium phosphate as the mineral are usually formed by physically mixing silk and calcium phosphate powder in a certain proportion, or using silk fibroin solution as a template to regulate calcium phosphate Morphology and structure of minerals. However, at present, these studies have not been able to simulate the formation of calcium phosphate minerals in an orderly complex growth induced by collagen fibers with a hierarchically assembled structure in biological bones.

The present application discloses a silk fibroin-calcium hydrogen phosphate complex with a multi-level structure by utilizing the self-assembly and template properties of silk fibroin to induce the ordered hybrid growth of calcium phosphate minerals and a preparation method thereof.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a kind of silk fibroin-calcium hydrogen phosphate complex with multi-level layered structure obtained by using silk fibroin as a template to induce and obtain the above-mentioned deficiencies in the prior art, and a preparation method thereof. The obtained silk fibroin-calcium hydrogen phosphate complex has an ordered assembly structure, the silk fibroin and the inorganic mineral calcium hydrogen phosphate are uniformly distributed, and the reaction conditions are mild, which can be carried out at room temperature, and the experiment has good repeatability.

For solving the above-mentioned technical problems, the technical scheme provided by the present invention is:

Provides a silk fibroin-calcium hydrogen phosphate complex obtained by inducing silk fibroin as a template, the complex shows a crystal structure, and is a monolayer rule formed by the growth of beta-sheet structure of silk fibroin-induced calcium hydrogen phosphate along the crystal axis The multi-layer mineral structure formed by the close and orderly arrangement of comb-shaped crystals or the plate-like structure obtained by further encapsulation of the multi-layer mineral structure, the silk fibroin is evenly distributed in the composite. On the one hand, silk fibroin induces the self-assembly of mineral molecules to form single-layer regular comb-shaped crystals, and on the other hand, it acts as a macromolecular template to further induce the self-assembly of single-layer regular comb-shaped crystals into larger hierarchical structures.

According to the above scheme, the mass percentage of silk fibroin in the silk fibroin-calcium hydrogen phosphate complex is 20-40%.

The present invention also provides the preparation method of the above-mentioned silk fibroin-calcium hydrogen phosphate complex obtained by using silk fibroin as a template, and the specific steps are as follows:

1) at room temperature, the degummed silk is soaked in the formic acid solution of calcium chloride to dissolve, then volatilize to remove the formic acid, and then wash with water to obtain a silk fibroin film;

2) Soak the silk fibroin film obtained in step 1) in a mixed solution of phosphoric acid and calcium chloride, let stand at room temperature for 2 to 72 hours, then transfer to a refrigerator of 2 to 4 °C for 1 to 4 days, and then mineralize in an ammonia atmosphere The silk fibroin-calcium hydrogen phosphate complex was obtained.

According to the above scheme, the formic acid solution of calcium chloride in step 1) is obtained by dissolving calcium chloride in formic acid, and the formic acid purity is 70-85 wt%.

According to the above scheme, the concentration of calcium chloride in the formic acid solution of calcium chloride in step 1) is 3-10 wt%.

According to the above scheme, the concentration of the degummed silk in the formic acid solution of calcium chloride in step 1) is 6-12 wt %.

According to the above scheme, the mixed solution of phosphoric acid and calcium chloride in step 2) is obtained by dissolving phosphoric acid and calcium chloride in water, wherein the calcium chloride concentration is 0.21～1.05mol/L, and the phosphorus element concentration in the mixed solution is 0.13～1.05 mol/L. 0.63mol/L.

According to the above scheme, the ammonia concentration in the ammonia atmosphere in step 2) is 100-300 ppm, the mineralization temperature is 10-30°C, and the mineralization time is 30min-48h.

The present invention also includes the application of the above-mentioned silk fibroin-calcium hydrogen phosphate complex in the field of biomedical materials.

The present application is based on the template property of silk fibroin combined with the self-assembly property to induce the ordered hybrid growth of calcium phosphate minerals to form a silk fibroin-calcium hydrogen phosphate complex with a multi-level layered structure, and the self-assembly property of silk fibroin induces small mineral molecules along the axis Assembled into larger mineral units, on the other hand, the template properties of silk fibroin induce the shaped mineral units to grow along the silk fibroin template to form a larger hierarchical mineral structure. Organic silk fibroin is evenly distributed in the obtained minerals, organic silk fibroin and calcium hydrogen phosphate are uniformly doped, and organic-inorganic composite hybrid structure minerals with single crystal characteristics are obtained. This multi-level structure of tincture-induced synthetic mineralization provides new ideas for more economical and efficient biomimetic synthesis, and can provide better materials and methods for bone regeneration and bone tissue repair.

The beneficial effects of the present invention are: 1. The silk fibroin-calcium hydrogen phosphate complex provided by the present invention has higher strength and better biocompatibility, and the multi-level structure of the silk fibroin-induced synthetic mineralization is more economical, More efficient biomimetic synthesis provides new ideas, and can provide better materials and methods for bone regeneration and bone tissue repair. 2. The preparation method provided by the present invention can be carried out at room temperature, the operation is simple, and the composite material of silk fibroin and calcium hydrogen phosphate can be obtained by rapid mineralization. The reaction process does not have high precision requirements on conditions such as reaction temperature and reaction time, and repeat The silk fibroin-calcium hydrogen phosphate composite material in different stages of mineralization can be obtained by adjusting the concentration of degummed silk in formic acid solution of calcium chloride and the mineralization time.

Description of drawings

Fig. 1 is the fluorescent staining photo of the silk fibroin-calcium hydrogen phosphate complex prepared in Example 1 of the present invention;

Fig. 2 is the infrared spectrogram of the silk fibroin-calcium hydrogen phosphate complex prepared in Example 1;

Fig. 3 is the SEM photograph of silk fibroin-calcium hydrogen phosphate composite prepared in Example 1;

Fig. 4 is the SEM photograph of silk fibroin-calcium hydrogen phosphate composite prepared in Example 2;

Fig. 5 is the TEM photograph of the silk fibroin-calcium hydrogen phosphate composite prepared in Example 2;

6 is a TEM photo of the silk fibroin-calcium hydrogen phosphate composite prepared in Example 3;

Fig. 7 is the single crystal electron diffraction photograph of the silk fibroin-calcium hydrogen phosphate composite prepared in Example 3;

Figure 8 is a photo of fluorescence staining of the silk fibroin-calcium hydrogen phosphate complex prepared in Example 4;

Fig. 9 is the SEM photograph of the silk fibroin-calcium hydrogen phosphate composite prepared in Example 4;

10 is a photo of the nanoindentation strength of the silk fibroin-calcium hydrogen phosphate composite mineral prepared in Example 4;

Figure 11 is the SEM photograph of the mineralized 3h silk fibroin-calcium hydrogen phosphate composite prepared in Example 5;

Figure 12 is the SEM photograph of the mineralized 24h silk fibroin-calcium hydrogen phosphate composite prepared in Example 5;

Figure 13 is the SEM photograph of the mineralized 3h silk fibroin-calcium hydrogen phosphate composite prepared in Example 6;

FIG. 14 is a SEM photograph of the mineralized 24h silk fibroin-calcium hydrogen phosphate complex prepared in Example 6. FIG.

Detailed ways

In order for those skilled in the art to better understand the technical solutions of the present invention, the present invention is further described in detail below with reference to the accompanying drawings.

Example 1

A method for inducing and obtaining a silk fibroin-calcium hydrogen phosphate complex using silk fibroin as a template, the specific steps are as follows:

1) Dissolve 0.8g calcium chloride in 15.2g formic acid (purity 85wt%), stir for 30min to dissolve calcium chloride, add 1.5824g degummed silk (the concentration of degummed silk is 9wt%) and place for 3h to dissolve, then quickly volatilize formic acid solution, and then washed with water to obtain a silk fibroin membrane;

2) Soak the obtained silk fibroin film in a mixed solution of phosphoric acid and calcium chloride. The mixed solution is obtained by adding 4.8554g CaCl ₂ and 2.8996 g H ₃ PO ₄ to 100 mL of water, and then it was left standing at room temperature for 72 hours and then transferred to a 4°C refrigerator for 4 days. Then, the container containing silk fibroin and mixed solution was placed in an environment with ammonia water (ammonia concentration in the air was 300 ppm) and mineralized at 25°C for 3 hours to obtain silk fibroin-calcium hydrogen phosphate complex.

Figure 1 shows the fluorescent staining photo of the silk fibroin-calcium hydrogen phosphate complex prepared in this example. It can be seen that the silk fibroin marked by fluorescent staining is distributed in minerals. The left side of the figure is the obtained silk fibroin containing silk fibroin The minerals in the right are the distribution of silk fibroin in the minerals. The results show that the distribution of silk fibroin in the minerals is relatively uniform. Figure 2 is the infrared spectrum of the obtained complex, showing that it contains characteristic peaks of silk fibroin and calcium hydrogen phosphate, wherein silk fibroin has a beta-sheet structure, confirming that the obtained mineralization product is of silk fibroin-calcium hydrogen phosphate Complex. Figure 3 is the SEM picture of the obtained composite, showing that the composite has the characteristics of crystal, the left picture is the grown monolayer crystal, the monolayer crystal has a very regular comb-shaped structure, and the length of the single comb tooth is about 1-3 μm , the diameter is about 200-500nm, and the gap between the comb teeth is about 10-100nm. The picture on the right shows the multilayer structure obtained by the neat, dense and orderly arrangement of monolayer crystals. EDS test results show that the content of silk fibroin accounts for about 32wt% of the hybrid minerals, which is half of the crystal content (mineral crystals account for about 60%).

Example 2

A method for inducing and obtaining a silk fibroin-calcium hydrogen phosphate complex using silk fibroin as a template, the specific steps are as follows:

1) Dissolve 0.8g calcium chloride in 15.2g formic acid (purity 85wt%), stir for 30min to dissolve calcium chloride, add 1.5824g degummed silk and place for 3h to dissolve, then quickly volatilize the formic acid solution, and wash with water to obtain a silk fibroin film.

2) Soak the obtained silk fibroin film in a mixed solution of phosphoric acid and calcium chloride. The mixed solution is obtained by adding 4.8554g CaCl ₂ and 2.8996 g H ₃ PO ₄ to 100 mL of water, and then it was left standing at room temperature for 72 hours and then transferred to a 4°C refrigerator for 4 days. On the next day, the container containing the silk fibroin and the mixed solution was placed in an environment with ammonia water (ammonia concentration in the air was 300 ppm) and mineralized at 25°C for 24 hours to obtain a silk fibroin-calcium hydrogen phosphate complex.

FIG. 4 shows the SEM photo of the silk fibroin-calcium hydrogen phosphate composite prepared in this example, which can capture the process of the composite minerals transforming from a dense multi-layer comb-like structure to a plate-like structure.

Figure 5 shows the TEM photo of the silk fibroin-calcium hydrogen phosphate composite prepared in this example. In the figure, the flocs are silk fibroin, and the particles distributed in it are calcium hydrogen phosphate minerals. It can be observed that the silk fibroin packs The overlying minerals grow regularly to form a comb-shaped branched structure.

Example 3

A method for inducing and obtaining a silk fibroin-calcium hydrogen phosphate complex using silk fibroin as a template, the specific steps are as follows:

1) Dissolve 0.8 g of calcium chloride in 15.2 g of formic acid (purity 85 wt %), and stir for 30 min to dissolve the calcium chloride. 1.5824g of degummed silk was added for 3 hours to dissolve, then the formic acid solution was quickly volatilized, and then washed with water to obtain a silk fibroin film.

2) The obtained silk fibroin film with a concentration of 9wt% was immersed in a mixed solution of phosphoric acid and calcium chloride. The mixed solution was obtained by adding 9.7108g CaCl ₂ and 5.7992g H ₃ PO ₄ to 100 mL of water. After standing at room temperature for 72 hours, it was transferred to Place in a refrigerator at 4°C for 4 days, place the container containing the silk fibroin and the mixed solution in an environment with ammonia water (ammonia concentration in the air is 300 ppm) and mineralize at room temperature (20°C) for 30 minutes to obtain silk fibroin-phosphoric acid Hydrogen calcium complex.

Figure 6 shows the TEM photo of the silk fibroin-calcium hydrogen phosphate composite prepared in this example, which shows the transmission morphology of a single-layer mineral, and it can be observed that several roots with a length of 200 nm grow regularly along the direction of the crystal axis -1μm minerals.

FIG. 7 is the single crystal electron diffraction photo of the calcium hydrogen phosphate mineral taken in FIG. 6 . It can be judged that the obtained mineral has the characteristics of single crystal from the single crystal lattice of the diffraction image.

Example 4

A method for inducing and obtaining a silk fibroin-calcium hydrogen phosphate complex using silk fibroin as a template, the specific steps are as follows:

1) Dissolve 0.8 g of calcium chloride in 15.2 g of formic acid (purity 85 wt %), and stir for 30 min to dissolve the calcium chloride. 1.5824g of degummed silk was added for 3 hours to dissolve, then the formic acid solution was quickly volatilized, and then washed with water to obtain a silk fibroin film.

2) Soak the obtained silk fibroin film in a mixed solution of phosphoric acid and calcium chloride. The mixed solution is obtained by adding 9.7108 g of CaCl ₂ and 5.7992 g of H ₃ PO ₄ to 100 mL of water. After standing at room temperature for 72 hours, it is transferred to a 4°C refrigerator for placement. For 4 days, the container containing the silk fibroin and the mixed solution was placed in an environment with ammonia water (ammonia concentration in the air was 300 ppm) and mineralized for 24 hours at room temperature (about 20°C) to obtain a silk fibroin-calcium hydrogen phosphate complex. .

Figure 8 is a photo of fluorescent dyeing of the silk fibroin-calcium hydrogen phosphate composite prepared in this example. Observe the distribution of the fluorescent dyed silk fibroin in the mineralized product in the composite material. The left is the white light microscope of the mineralized product. Morphology map, the right is the fluorescence microscope morphology map of silk fibroin after staining. Since the imaging morphology of white light and silk fibroin excited by fluorescence microscope is consistent, it proves that silk fibroin is uniformly distributed in minerals.

Fig. 9 is a SEM photograph of the silk fibroin-calcium hydrogen phosphate composite prepared in this example. After 24 hours of mineralization, the obtained composite is a plate-like structure obtained by dense growth and coating of a comb-shaped single crystal structure, and the plate length is about 1 -10μm, about 200-800nm thick. Figure 10 is a photo of the nanoindentation strength of the silk fibroin-calcium hydrogen phosphate composite prepared in this example, which shows that the obtained composite mineral has a certain strength, and the strength is about 0.77-1.49GPa.

Example 5

A method for inducing and obtaining a silk fibroin-calcium hydrogen phosphate complex using silk fibroin as a template, the specific steps are as follows:

1) Dissolve 0.8g calcium chloride in 15.2g formic acid, stir for 30min to dissolve calcium chloride, add 1.02g degummed silk (the concentration of degummed silk is 6wt%) and place for 3h to dissolve, then quickly volatilize the formic acid solution, then wash with water to obtain silk fibroin membrane;

2) Soak the obtained silk fibroin film in a mixed solution of phosphoric acid and calcium chloride. The mixed solution is obtained by adding 4.8554g CaCl ₂ and 2.8996 g H ₃ PO ₄ to 100 mL of water, and then it was left standing at room temperature for 72 hours and then transferred to a 4°C refrigerator for 4 days. Then, the container containing the silk fibroin and the mixed solution was placed in an environment with ammonia water (ammonia concentration in the air was 300 ppm) and mineralized at room temperature (about 20°C) to obtain a silk fibroin-calcium hydrogen phosphate complex. .

Fig. 11 is a SEM photograph of the silk fibroin-calcium hydrogen phosphate composite prepared under the condition of mineralization for 3 hours in this example. It can be observed that the mineralization is a multi-layered mineral formed by the arrangement of single-layer comb-shaped crystals, but each layer of comb-shaped The crystals are arranged sparsely. In the single-layer comb-shaped crystal, the length of a single comb tooth is about 1-3 μm, the diameter is about 200-500 nm, and the space between the comb teeth is about 10-500 nm.

Fig. 12 is a SEM photograph of the silk fibroin-calcium hydrogen phosphate composite prepared under the condition of mineralization for 24 h in this example. It can be observed that the mineralization is a multi-layered mineral obtained by arranging single-layer comb-shaped crystals, and each layer of comb-shaped crystals The arrangement is dense, but the plate-like structure has not yet been formed. In the single-layer comb-shaped crystal, the length of a single comb tooth is about 1-5 μm, the diameter is about 200-800 nm, and the space between the comb teeth is about 10-50 nm.

Example 6

A method for inducing and obtaining a silk fibroin-calcium hydrogen phosphate complex using silk fibroin as a template, the specific steps are as follows:

1) Dissolve 0.8g calcium chloride in 15.2g formic acid, stir for 30min to dissolve calcium chloride, add 2.18g degummed silk (the concentration of degummed silk is 12wt%) and leave for 3h to dissolve, then quickly volatilize the formic acid solution, then wash with water to obtain silk fibroin membrane;

2) Soak the obtained silk fibroin film in a mixed solution of phosphoric acid and calcium chloride. The mixed solution is obtained by adding 4.8554g CaCl ₂ and 2.8996 g H ₃ PO ₄ to 100 mL of water, and then it was left standing at room temperature for 72 hours and then transferred to a 4°C refrigerator for 4 days. Then, the container containing the silk fibroin and the mixed solution was placed in an environment with ammonia water (ammonia concentration in the air was 300 ppm) and mineralized at room temperature (about 20°C) to obtain a silk fibroin-calcium hydrogen phosphate complex. .

Fig. 13 is the SEM photograph of the silk fibroin-calcium hydrogen phosphate composite prepared under the condition of mineralization for 3 hours in this example, it can be observed that the degummed silk is mineralized for a shorter time when the concentration of degummed silk is higher in the formic acid solution of calcium chloride The layers of comb-shaped crystals of the multi-layer minerals grown below are relatively compactly arranged. In the comb-shaped crystal, the length of a single comb tooth is about 1-5 μm, the diameter is about 300-500 nm, and the space between the comb teeth is about 10-100 nm. The multilayer minerals are approximately 200-800 nm thick and 1-10 μm long.

Figure 14 is an SEM photo of the silk fibroin-calcium hydrogen phosphate composite prepared under the condition of mineralization for 24 hours in this example. It can be observed that the degummed silk has been mineralized within 24 hours when the concentration of the degummed silk in the formic acid solution of calcium chloride is relatively high. It grows into a very dense plate-like structure with a sawtooth shape on the sides of the plate. The plate length is 1-10 μm and the thickness is about 200-800 nm.

From the above detailed description of the embodiments of the present invention, it can be understood that the reaction conditions of the present invention are mild, the operation is simple, can be carried out at room temperature, the experiment repeatability is good, and the organic component silk fibroin and the inorganic mineral calcium hydrogen phosphate are in the obtained mineralized material. evenly distributed. And the silk fibroin-calcium hydrogen phosphate composites at different stages of mineralization can be obtained by adjusting the concentration and mineralization time of degummed silk in formic acid solution of calcium chloride, specifically, degummed silk in formic acid solution of calcium chloride. When the treatment concentration is high (9-12wt%) and the mineralization time is short (1-12h), a multi-level layered mineral structure with dense and orderly arrangement of comb-tooth-like single crystal minerals is obtained, and the mineralization time is long (more than 24h). The multi-level layered mineral structure is coated to obtain a plate-like mineral structure; when the degummed silk is treated in a calcium chloride formic acid solution at a low concentration (6-8wt%), the mineralization within 24h is all comb-shaped single crystals. The multi-level layered mineral structure with dense and orderly arrangement of minerals, and the length of mineralization time will affect the density of single crystal minerals. The invention can provide a certain theoretical basis for the simulation study of the growth of human bone structure.

It should be understood that the above embodiments are only exemplary implementations adopted to illustrate the principle of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.

The upper and lower limits and interval values of each raw material of the present invention, as well as the upper and lower limits and interval values of process parameters (such as silk fibroin film concentration, precursor solution concentration and mineralization time, etc.) Examples are given.

Claims (9)

1. The fibroin-calcium hydrogen phosphate compound is characterized by showing a crystal structure, wherein fibroin of a beta-sheet structure induces calcium hydrogen phosphate to grow along the axial direction of the crystal to form a single-layer regular comb-shaped crystal, the single-layer regular comb-shaped crystal is tightly and orderly arranged to form a multi-layer mineral structure or a multi-layer mineral structure, the multi-layer mineral structure is further wrapped to form a plate-shaped structure, and fibroin is uniformly distributed in the compound.

2. The fibroin-calcium hydrogen phosphate composite obtained by induction with fibroin as a template according to claim 1, wherein the mass percentage content of fibroin in the fibroin-calcium hydrogen phosphate composite is 20-40%.

3. A method for preparing the fibroin-calcium hydrogen phosphate compound obtained by induction with fibroin as a template, as claimed in claim 1 or 2, is characterized by comprising the following steps:

1) soaking degummed silk in a formic acid solution of calcium chloride at room temperature for dissolving, then volatilizing to remove formic acid, and washing with water to obtain a fibroin membrane;

2) soaking the fibroin film obtained in the step 1) in a mixed solution of phosphoric acid and calcium chloride, standing at room temperature for 2-72 h, turning to a refrigerator at 2-4 ℃, standing for 1-4 days, and then mineralizing in an ammonia atmosphere to obtain the fibroin-calcium hydrogen phosphate compound.

4. The method for preparing the fibroin-calcium hydrogen phosphate composite obtained by induction with fibroin as a template according to claim 3, wherein the formic acid solution of calcium chloride in the step 1) is obtained by dissolving calcium chloride in formic acid, and the purity of the formic acid is 70-85 wt%.

5. The method for preparing the fibroin-calcium hydrogen phosphate composite obtained by induction with fibroin as a template according to claim 3, wherein the concentration of calcium chloride in the formic acid solution of calcium chloride in the step 1) is 3-10 wt%.

6. The method for preparing the fibroin-calcium hydrogen phosphate composite obtained by induction with fibroin as a template according to claim 3, wherein the concentration of degummed silk in the formic acid solution of calcium chloride in step 1) is 6-12 wt%.

7. The method for preparing the fibroin-calcium hydrogen phosphate composite obtained by induction with fibroin as a template according to claim 3, wherein the mixed solution of phosphoric acid and calcium chloride in the step 2) is obtained by dissolving phosphoric acid and calcium chloride in water, wherein the concentration of calcium chloride is 0.21-1.05 mol/L, and the concentration of phosphorus in the mixed solution is 0.13-0.63 mol/L.

8. The preparation method of the silk fibroin-calcium hydrogen phosphate compound obtained by induction with silk fibroin as a template according to claim 3, wherein ammonia concentration in the ammonia gas atmosphere in the step 2) is 100-300 ppm, mineralization temperature is 10-30 ℃, and mineralization time is 30 min-48 h.

9. The use of the fibroin-calcium hydrogen phosphate composite obtained by induction using fibroin as a template according to claim 1 or 2 in the field of biomedical materials.

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