Surface coating modified calcium phosphate microspheres and preparation method thereof

Abstract

The invention discloses a surface coating modified calcium phosphate microsphere and a preparation method thereof, and belongs to the technical field of calcium phosphate microsphere preparation. The surface coating modified calcium phosphate microspheres are prepared from the following components in parts by weight: 60 to 68 parts of calcium phosphate ceramic powder, 20 to 32 parts of modified bioactive bodies, 8 to 12 parts of composite pore forming agents and 2 to 5 parts of binding agents, the modified bioactive body is prepared from vinyltriethoxysilane, butyl dibutyl phosphate, citric acid, calcium acetate, magnesium sulfate and polyether-ether-ketone fibers, and the composite pore-forming agent is prepared from octyl dimethyl tertiary amine, epoxy chloropropane, hydrolyzed soybean protein and starch. The calcium phosphate microspheres prepared by the method have excellent porosity and biological activity.

Description

Technical Field

[0001] The invention belongs to the technical field of calcium phosphate microsphere preparation, and particularly relates to surface-coated modified calcium phosphate microspheres and a preparation method thereof. Background Art

[0002] With the continuous advancement of modern medical technology, people's requirements for bone defect repair materials are increasing. They expect that the materials can not only effectively fill the bone defect, but also have good biocompatibility, bioactivity and a suitable degradation rate to promote the formation of new bone and tissue regeneration. Calcium phosphate ceramics, as a classic bone defect filling material, have been widely used in clinical practice. However, although traditional calcium phosphate ceramic block materials have good integrity and are easy to fill, their shape is fixed and it is difficult to accurately match complex bone defects. In contrast, calcium phosphate ceramic granular materials are more suitable for filling irregular bone defects due to their good adaptability and low manufacturing cost.

[0003] Calcium phosphate ceramic particles are mainly divided into two types: irregularly shaped particles and spherical particles. Irregularly shaped particles are mainly obtained by crushing bulk calcium phosphate ceramics. Although they can adapt to complex bone defect shapes, their sharp edges and corners may cause inflammation and damage to surrounding tissues after implantation in the body. In contrast, spherical particles, namely calcium phosphate microparticles, can effectively avoid this problem. Calcium phosphate microspheres have better cell compatibility and tissue compatibility, can reduce adverse reactions after implantation, and are conducive to cell adhesion and migration as well as the later growth of bone tissue.

[0004] Patent CN113135769B discloses a surface-coated modified porous calcium phosphate ceramic microsphere and its preparation method and application, including: 1) mixing calcium phosphate ceramic powder, excipient and pore-forming agent uniformly to obtain a solid phase mixture, adding a binder solution to the solid phase mixture, uniformly mixing, and obtaining a plastic wet material; 2) loading the plastic wet material into the extrusion device of the extrusion spheronization machine to obtain a strip cylindrical material, and then pouring the material into the spheronization device, rolling to obtain microspheres; 3) adding biologically active powder to the microspheres of the spheronization device to obtain microspheres with surface-coated biologically active substances; 4) drying the microspheres and placing them in a sintering furnace for high-temperature sintering to obtain surface-coated modified porous calcium phosphate ceramic microspheres. The size and porous structure of the microspheres prepared by this method can be adjusted adaptably, and the surface has high biological activity. However, the porosity and biological activity of the microspheres prepared by this method still have room for improvement. Summary of the invention

[0005] The object of the present invention is to provide a surface-coated modified calcium phosphate microsphere and a preparation method thereof, so as to solve the technical problems of poor porosity and poor biological activity of calcium phosphate microspheres in the prior art.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The invention provides a surface-coated modified calcium phosphate microsphere, which is composed of the following components in parts by weight: 60-68 parts of calcium phosphate ceramic powder, 20-32 parts of modified bioactive body, 8-12 parts of composite pore-forming agent, and 2-5 parts of binder, wherein the modified bioactive body is prepared from vinyl triethoxysilane, dibutyl butyl phosphate, citric acid, calcium acetate, magnesium sulfate and polyetheretherketone fiber, and the composite pore-forming agent is prepared from octyl dimethyl tertiary amine, epichlorohydrin, hydrolyzed soybean protein and starch.

[0008] Preferably, the method for preparing the modified biologically active substance comprises the following steps:

[0009] Q1: Add vinyl triethoxysilane to a container containing a mixed solution of deionized water and ethanol, stir at room temperature, add dibutyl butyl phosphate, stir until completely dissolved, add citric acid, and then add calcium acetate and magnesium sulfate, mix and stir to obtain a mixed solution;

[0010] Q2: The obtained mixed solution is statically aged to obtain a wet gel, which is then dried, heat treated, and ground to obtain particles;

[0011] Q3: Add the particles into a container filled with deionized water, disperse them by ultrasonication, then add the polyetheretherketone fiber into the container, shake and stir, filter, and dry to obtain a modified bioactive body.

[0012] In the above process, deionized water and ethanol are first used as solvents, vinyl triethoxysilane, dibutyl phosphate, calcium acetate and magnesium sulfate are used as molecular precursors, and citric acid is used as a catalyst. The particles are prepared by a sol-gel method, and then the particles are compounded with polyetheretherketone fibers to prepare a modified bioactive body.

[0013] Preferably, in Q1, the dosage ratio of vinyl triethoxysilane, deionized water, ethanol, dibutyl phosphate, citric acid, calcium acetate and magnesium sulfate is (58-62) g: (20-28) mL: (13-18) mL: (22-31) g: (2-5) g: (9-13) g: (11-16) g, the stirring time at room temperature is 30-45 min, and the mixing and stirring time is 4-6 h.

[0014] Preferably, in Q2, the static aging temperature is 28-32°C, the aging time is 20-28h, first dried at 60°C for 24h, then dried at 120°C for 24h, and the heat treatment process is: heating to 400°C at a heating rate of 2°C / min, keeping warm for 3-5h, then heating to 650°C at a heating rate of 2°C / min, keeping warm for 3-4h, and grinding to a particle size of 60-70μm.

[0015] Preferably, in Q3, the dosage ratio of the particulate matter, deionized water and polyetheretherketone fiber is (20-36) g: (10-15) mL: (12-22) g, the ultrasonic dispersion time is 45-60 min, the oscillation stirring time is 3-5 h, the drying temperature is 70-90 ° C, and the time is 20-24 h.

[0016] Preferably, the preparation method of the composite pore-forming agent comprises the following steps:

[0017] S1: Add methanol to a container, slowly add octyl dimethyl tertiary amine under magnetic stirring, then slowly add epichlorohydrin, stir to react, after the reaction is completed, rotary evaporate, then add anhydrous ether, let stand, remove the supernatant, wash, centrifuge, and vacuum dry to obtain compound 1;

[0018] S2: adding the hydrolyzed soy protein to a container filled with deionized water, stirring until completely dissolved, adjusting the pH, then adding compound 1, heating and stirring to react, continuing to adjust the pH, freeze-drying, washing, freeze-drying again, and grinding to obtain compound 2;

[0019] S3: Compound 2 is added to distilled water, and after stirring and mixing, starch is added, and the mixture is further stirred and mixed, and dried to obtain a composite pore-forming agent.

[0020] In the above process, octyl dimethyl tertiary amine and epichlorohydrin are used as raw materials to prepare compound 1, and then hydrolyzed soy protein is used as a raw material to undergo a quaternization reaction with compound 1 to obtain compound 2, and then compound 2 is mixed with starch to prepare a composite pore-forming agent.

[0021] Preferably, in S1, the amount ratio of methanol, octyl dimethyl tertiary amine and epichlorohydrin is (60-80) mL: (5.24-8.12) g: (6.16-10.08) g, the stirring reaction temperature is 20-22°C, the reaction time is 10-12h, the standing time is 10-15min, washing is performed with anhydrous ether, the centrifugal speed is 8000-12000rpm, the centrifugal time is 15-20min, the vacuum drying temperature is 70-85°C, and the time is 2-5h.

[0022] Preferably, in S2, the average molecular weight of the hydrolyzed soy protein is 3000Da, the dosage ratio of the hydrolyzed soy protein, deionized water and compound 1 is (30-45) g: (75-125) mL: (40-55) g, the pH is adjusted to 9.9-10.1 with a 25wt% sodium hydroxide aqueous solution, the heating and stirring reaction temperature is 50-55°C, the reaction time is 5-8h, 1mol / L hydrochloric acid is added to adjust the pH to 5-7, and the mixture is washed with acetone; in S3, the dosage ratio of compound 2, distilled water and starch is (8-12) g: (10-15) mL: (20-28) g, and the mixing and stirring time is 30-45min.

[0023] Preferably, the method for preparing the surface-coated modified calcium phosphate microspheres comprises the following steps:

[0024] Step 1: Evenly mix the calcium phosphate ceramic powder and the composite pore-forming agent, then add the binder, and continue mixing and stirring to obtain a mixture;

[0025] Step 2: adding the mixture to the extrusion device of the extrusion spheronization machine, extruding and rolling to obtain calcium phosphate microspheres, and then adding the modified bioactive body to the calcium phosphate microspheres, coating, drying, and calcining to obtain surface-coated modified calcium phosphate microspheres.

[0026] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0027] 1. The present invention first uses vinyl triethoxysilane, dibutyl butyl phosphate, citric acid, calcium acetate, magnesium sulfate and polyetheretherketone fiber as raw materials to prepare a modified bioactive body, and then uses octyl dimethyl tertiary amine, epichlorohydrin, hydrolyzed soy protein and starch as raw materials to prepare a composite pore-forming agent. The modified bioactive body and the composite pore-forming agent are added to the preparation process of calcium phosphate microspheres, which can effectively improve their porosity and biological activity.

[0028] 2. The present invention adds the prepared modified bioactive body to calcium phosphate microspheres, which can effectively improve its biological activity. The silicates, phosphates, calcium salts and magnesium salts contained in the modified bioactive body can promote the increase of active sites on the surface of the microspheres and improve its biological activity. At the same time, the addition of the modified bioactive body can improve the surface properties of the calcium phosphate microspheres, such as roughness, hydrophilicity and charge distribution, which helps to enhance the interaction between the microspheres and cells, thereby promoting cell adhesion, proliferation and differentiation. The addition of the modified bioactive body will increase the drug loading capacity of the calcium phosphate microspheres, enhance the drug release performance, and achieve sustained and efficient drug release. The modified bioactive body contains inorganic components similar to human bone tissue and forms a good composite structure with the calcium phosphate microspheres, which can make it have a stronger bone conduction effect.

[0029] 3. The present invention adds the prepared composite pore-forming agent to calcium phosphate microspheres, which can effectively improve its porosity. Compound 2 has excellent surface activity and can effectively reduce the surface tension of the solution, improve the dispersibility and stability of starch particles in calcium phosphate powder, and the quaternary ammonium salt group contained in compound 2 has good antibacterial properties and biocompatibility, which helps to improve the biological properties of calcium phosphate materials. After the starch particles as pore-forming agents are uniformly dispersed in the calcium phosphate powder, the gaps left by the burning of starch form a porous structure after sintering. The surface activity of compound 2 further optimizes the dispersion state of starch particles, accurately controls the size and distribution of pores, reduces pore blockage, and significantly improves the porosity of calcium phosphate materials after sintering. At the same time, the presence of compound 2 can also promote the compatibility of calcium phosphate materials with biological tissues, which helps the adhesion and growth of cells. DETAILED DESCRIPTION

[0030] The following will be described clearly and completely in conjunction with 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.

[0031] Example 1: This example discloses a method for preparing a modified biologically active substance, comprising the following steps:

[0032] Q1: Add 60g of vinyl triethoxysilane to a container containing a mixed solution of 24mL of deionized water and 15.5mL of ethanol, stir at room temperature for 45min, add 26.5g of dibutyl butyl phosphate, stir until completely dissolved, add 3.5g of citric acid, then add 11g of calcium acetate and 13.5g of magnesium sulfate, mix and stir for 6h to obtain a mixed solution;

[0033] Q2: The obtained mixed solution was aged at 28°C for 24 hours to obtain a wet gel, which was first dried at 60°C for 24 hours, then dried at 120°C for 24 hours, heated to 400°C at a heating rate of 2°C / min, kept warm for 4 hours, and then heated to 650°C at a heating rate of 2°C / min, kept warm for 3 hours, and ground to a particle size of 60 μm to obtain particles;

[0034] Q3: 28 g of the particles were added to a container containing 12.5 mL of deionized water, and ultrasonically dispersed for 60 min. Then 17 g of polyetheretherketone fiber was added to the container, shaken and stirred for 4 h, filtered, and dried at 80°C for 24 h to obtain a modified bioactive body.

[0035] This embodiment discloses a method for preparing a composite pore-forming agent, comprising the following steps:

[0036] S1: 70 mL of methanol was added to a container, 6.32 g of octyl dimethyl tertiary amine was slowly added under magnetic stirring, and then 8.12 g of epichlorohydrin was slowly added, and the mixture was stirred at 20°C for 12 h. After the reaction was completed, the mixture was rotary evaporated, and then anhydrous ether was added. The mixture was allowed to stand for 15 min, the supernatant was removed, and the mixture was washed with anhydrous ether. The mixture was centrifuged at 12000 rpm for 20 min, and vacuum dried at 85°C for 4 h to obtain compound 1;

[0037] S2: 37.5 g of hydrolyzed soy protein with an average molecular weight of 3000 Da was added to a container filled with 100 mL of deionized water, and stirred until completely dissolved. The pH was adjusted to 10 with a 25 wt% sodium hydroxide aqueous solution, and then 47.5 g of compound 1 was added. The mixture was stirred at 55 ° C for 6 h, and 1 mol / L hydrochloric acid was added to continue to adjust the pH to 6. The mixture was freeze-dried, washed with acetone, freeze-dried again, and ground to obtain compound 2;

[0038] S3: 10 g of compound 2 was added to 12.5 mL of distilled water, and after stirring, 24 g of starch was added, and the mixture was continued to be stirred for 45 min, and dried to obtain a composite pore-forming agent.

[0039] This embodiment discloses a surface-coated modified calcium phosphate microsphere, which is composed of the following components in parts by weight: 64 parts of calcium phosphate ceramic powder, 26 parts of modified bioactive body, 10 parts of composite pore-forming agent, and 3.5 parts of binder.

[0040] This embodiment discloses a method for preparing surface-coated modified calcium phosphate microspheres, comprising the following steps:

[0041] Step 1: Evenly mix the calcium phosphate ceramic powder and the composite pore-forming agent, then add the binder, and continue mixing and stirring to obtain a mixture;

[0042] Step 2: adding the mixture to the extrusion device of the extrusion spheronization machine, extruding and rolling to obtain calcium phosphate microspheres, and then adding the modified bioactive body to the calcium phosphate microspheres, coating, drying, and calcining to obtain surface-coated modified calcium phosphate microspheres.

[0043] Example 2: This example discloses a method for preparing a modified biologically active substance, comprising the following steps:

[0044] Q1: Add 58g of vinyl triethoxysilane to a container containing a mixed solution of 20mL of deionized water and 13mL of ethanol, stir at room temperature for 45min, add 22g of dibutyl butyl phosphate, stir until completely dissolved, add 2g of citric acid, then add 9g of calcium acetate and 11g of magnesium sulfate, mix and stir for 6h to obtain a mixed solution;

[0045] Q2: The obtained mixed solution was aged at 28°C for 24 hours to obtain a wet gel, which was first dried at 60°C for 24 hours, then dried at 120°C for 24 hours, heated to 400°C at a heating rate of 2°C / min, kept warm for 4 hours, and then heated to 650°C at a heating rate of 2°C / min, kept warm for 3 hours, and ground to a particle size of 60 μm to obtain particles;

[0046] Q3: 20 g of the particles were added to a container containing 10 mL of deionized water, and ultrasonically dispersed for 60 min. Then 12 g of polyetheretherketone fiber was added to the container, shaken and stirred for 4 h, filtered, and dried at 80°C for 24 h to obtain a modified bioactive body.

[0047] This embodiment discloses a method for preparing a composite pore-forming agent, comprising the following steps:

[0048] S1: 60 mL of methanol was added to the container, 5.24 g of octyl dimethyl tertiary amine was slowly added under magnetic stirring, and then 6.16 g of epichlorohydrin was slowly added, and the mixture was stirred at 20°C for 12 h. After the reaction was completed, the mixture was rotary evaporated, and then anhydrous ether was added. The mixture was allowed to stand for 15 min, the supernatant was removed, and the mixture was washed with anhydrous ether. The mixture was centrifuged at 12000 rpm for 20 min, and vacuum dried at 85°C for 4 h to obtain compound 1;

[0049] S2: 30 g of hydrolyzed soy protein with an average molecular weight of 3000 Da was added to a container filled with 75 mL of deionized water, stirred until completely dissolved, and the pH was adjusted to 10 with a 25 wt% sodium hydroxide aqueous solution, and then 40 g of compound 1 was added, stirred at 55 ° C for 6 h, and 1 mol / L hydrochloric acid was added to continue to adjust the pH to 6, freeze-dried, washed with acetone, freeze-dried again, and ground to obtain compound 2;

[0050] S3: 8 g of compound 2 was added to 10 mL of distilled water, and after stirring, 20 g of starch was added, and the mixture was continued to be stirred for 45 min, and dried to obtain a composite pore-forming agent.

[0051] This embodiment discloses a surface-coated modified calcium phosphate microsphere, which is composed of the following components in parts by weight: 60 parts of calcium phosphate ceramic powder, 20 parts of modified bioactive body, 8 parts of composite pore-forming agent, and 2 parts of binder.

[0052] This embodiment discloses a method for preparing surface-coated modified calcium phosphate microspheres, comprising the following steps:

[0053] Step 1: Evenly mix the calcium phosphate ceramic powder and the composite pore-forming agent, then add the binder, and continue mixing and stirring to obtain a mixture;

[0054] Step 2: adding the mixture to the extrusion device of the extrusion spheronization machine, extruding and rolling to obtain calcium phosphate microspheres, and then adding the modified bioactive body to the calcium phosphate microspheres, coating, drying, and calcining to obtain surface-coated modified calcium phosphate microspheres.

[0055] Example 3: This example discloses a method for preparing a modified biologically active substance, comprising the following steps:

[0056] Q1: Add 62g of vinyl triethoxysilane to a container containing a mixed solution of 28mL of deionized water and 18mL of ethanol, stir at room temperature for 45min, add 31g of dibutyl butyl phosphate, stir until completely dissolved, add 5g of citric acid, then add 13g of calcium acetate and 16g of magnesium sulfate, mix and stir for 6h to obtain a mixed solution;

[0057] Q2: The obtained mixed solution was aged at 28°C for 24 hours to obtain a wet gel, which was first dried at 60°C for 24 hours, then dried at 120°C for 24 hours, heated to 400°C at a heating rate of 2°C / min, kept warm for 4 hours, and then heated to 650°C at a heating rate of 2°C / min, kept warm for 3 hours, and ground to a particle size of 60 μm to obtain particles;

[0058] Q3: 36 g of the particles were added to a container containing 15 mL of deionized water, and ultrasonically dispersed for 60 min. Then 22 g of polyetheretherketone fiber was added to the container, shaken and stirred for 4 h, filtered, and dried at 80°C for 24 h to obtain a modified bioactive body.

[0059] This embodiment discloses a method for preparing a composite pore-forming agent, comprising the following steps:

[0060] S1: 80 mL of methanol was added to a container, 8.12 g of octyl dimethyl tertiary amine was slowly added under magnetic stirring, and then 10.08 g of epichlorohydrin was slowly added, and the mixture was stirred at 20°C for 12 h. After the reaction was completed, the mixture was rotary evaporated, and then anhydrous ether was added. The mixture was allowed to stand for 15 min, the supernatant was removed, and the mixture was washed with anhydrous ether. The mixture was centrifuged at 12000 rpm for 20 min, and vacuum dried at 85°C for 4 h to obtain compound 1;

[0061] S2: 45 g of hydrolyzed soy protein with an average molecular weight of 3000 Da was added to a container filled with 125 mL of deionized water, stirred until completely dissolved, and the pH was adjusted to 10 with a 25 wt% sodium hydroxide aqueous solution, and then 55 g of compound 1 was added, stirred at 55 ° C for 6 h, and 1 mol / L hydrochloric acid was added to continue to adjust the pH to 6, freeze-dried, washed with acetone, freeze-dried again, and ground to obtain compound 2;

[0062] S3: 12 g of compound 2 was added to 15 mL of distilled water, and after stirring, 28 g of starch was added, and the mixture was continued to be stirred for 45 min, and dried to obtain a composite pore-forming agent.

[0063] This embodiment discloses a surface-coated modified calcium phosphate microsphere, which is composed of the following components in parts by weight: 68 parts of calcium phosphate ceramic powder, 32 parts of modified bioactive body, 12 parts of composite pore-forming agent, and 5 parts of binder.

[0064] This embodiment discloses a method for preparing surface-coated modified calcium phosphate microspheres, comprising the following steps:

[0065] Step 1: Evenly mix the calcium phosphate ceramic powder and the composite pore-forming agent, then add the binder, and continue mixing and stirring to obtain a mixture;

[0066] Step 2: adding the mixture to the extrusion device of the extrusion spheronization machine, extruding and rolling to obtain calcium phosphate microspheres, and then adding the modified bioactive body to the calcium phosphate microspheres, coating, drying, and calcining to obtain surface-coated modified calcium phosphate microspheres.

[0067] Example 4: This example discloses a method for preparing a modified biologically active substance, comprising the following steps:

[0068] Q1: Add 59g of vinyl triethoxysilane to a container containing a mixed solution of 22mL of deionized water and 14mL of ethanol, stir at room temperature for 45min, add 24g of dibutyl butyl phosphate, stir until completely dissolved, add 3g of citric acid, then add 10g of calcium acetate and 12g of magnesium sulfate, mix and stir for 6h to obtain a mixed solution;

[0069] Q2: The obtained mixed solution was aged at 28°C for 24 hours to obtain a wet gel, which was first dried at 60°C for 24 hours, then dried at 120°C for 24 hours, heated to 400°C at a heating rate of 2°C / min, kept warm for 4 hours, and then heated to 650°C at a heating rate of 2°C / min, kept warm for 3 hours, and ground to a particle size of 60 μm to obtain particles;

[0070] Q3: 24 g of the particles were added to a container containing 11 mL of deionized water, and ultrasonically dispersed for 60 min. Then 14 g of polyetheretherketone fiber was added to the container, shaken and stirred for 4 h, filtered, and dried at 80°C for 24 h to obtain a modified bioactive body.

[0071] This embodiment discloses a method for preparing a composite pore-forming agent, comprising the following steps:

[0072] S1: 65 mL of methanol was added to the container, 5.87 g of octyl dimethyl tertiary amine was slowly added under magnetic stirring, and then 7.23 g of epichlorohydrin was slowly added, and the mixture was stirred at 20°C for 12 h. After the reaction was completed, the mixture was rotary evaporated, and then anhydrous ether was added. The mixture was allowed to stand for 15 min, the supernatant was removed, and the mixture was washed with anhydrous ether. The mixture was centrifuged at 12000 rpm for 20 min, and vacuum dried at 85°C for 4 h to obtain compound 1;

[0073] S2: 32 g of hydrolyzed soy protein with an average molecular weight of 3000 Da was added to a container filled with 85 mL of deionized water, stirred until completely dissolved, and the pH was adjusted to 10 with a 25 wt% sodium hydroxide aqueous solution, and then 42 g of compound 1 was added, stirred at 55 ° C for 6 h, and 1 mol / L hydrochloric acid was added to continue to adjust the pH to 6, freeze-dried, washed with acetone, freeze-dried again, and ground to obtain compound 2;

[0074] S3: 9 g of compound 2 was added to 11 mL of distilled water, and after stirring, 22 g of starch was added, and the mixture was continued to be stirred for 45 min, and dried to obtain a composite pore-forming agent.

[0075] This embodiment discloses a surface-coated modified calcium phosphate microsphere, which is composed of the following components in parts by weight: 62 parts of calcium phosphate ceramic powder, 22 parts of modified bioactive body, 9 parts of composite pore-forming agent, and 3 parts of binder.

[0076] This embodiment discloses a method for preparing surface-coated modified calcium phosphate microspheres, comprising the following steps:

[0077] Step 1: Evenly mix the calcium phosphate ceramic powder and the composite pore-forming agent, then add the binder, and continue mixing and stirring to obtain a mixture;

[0078] Step 2: adding the mixture to the extrusion device of the extrusion spheronization machine, extruding and rolling to obtain calcium phosphate microspheres, and then adding the modified bioactive body to the calcium phosphate microspheres, coating, drying, and calcining to obtain surface-coated modified calcium phosphate microspheres.

[0079] Example 5: This example discloses a method for preparing a modified biologically active substance, comprising the following steps:

[0080] Q1: Add 61g of vinyl triethoxysilane to a container containing a mixed solution of 26mL of deionized water and 16mL of ethanol, stir at room temperature for 45min, add 28g of dibutyl butyl phosphate, stir until completely dissolved, add 4g of citric acid, then add 12g of calcium acetate and 14g of magnesium sulfate, mix and stir for 6h to obtain a mixed solution;

[0081] Q2: The obtained mixed solution was aged at 28°C for 24 hours to obtain a wet gel, which was first dried at 60°C for 24 hours, then dried at 120°C for 24 hours, heated to 400°C at a heating rate of 2°C / min, kept warm for 4 hours, and then heated to 650°C at a heating rate of 2°C / min, kept warm for 3 hours, and ground to a particle size of 60 μm to obtain particles;

[0082] Q3: 32 g of the particles were added to a container containing 14 mL of deionized water, and ultrasonically dispersed for 60 min. Then 20 g of polyetheretherketone fiber was added to the container, shaken and stirred for 4 h, filtered, and dried at 80°C for 24 h to obtain a modified bioactive body.

[0083] This embodiment discloses a method for preparing a composite pore-forming agent, comprising the following steps:

[0084] S1: 75 mL of methanol was added to the container, 7.15 g of octyl dimethyl tertiary amine was slowly added under magnetic stirring, and then 9.05 g of epichlorohydrin was slowly added, and the mixture was stirred at 20°C for 12 h. After the reaction was completed, the mixture was rotary evaporated, and then anhydrous ether was added. The mixture was allowed to stand for 15 min, the supernatant was removed, and the mixture was washed with anhydrous ether. The mixture was centrifuged at 12000 rpm for 20 min, and vacuum dried at 85°C for 4 h to obtain compound 1;

[0085] S2: 43 g of hydrolyzed soy protein with an average molecular weight of 3000 Da was added to a container filled with 105 mL of deionized water, and stirred until completely dissolved. The pH was adjusted to 10 with a 25 wt% sodium hydroxide aqueous solution, and then 53 g of compound 1 was added. The mixture was stirred at 55 °C for 6 h, and 1 mol / L hydrochloric acid was added to continue adjusting the pH to 6. The mixture was freeze-dried, washed with acetone, freeze-dried again, and ground to obtain compound 2.

[0086] S3: 11 g of compound 2 was added to 14 mL of distilled water, and after stirring, 26 g of starch was added, and the mixture was continued to be stirred for 45 min, and dried to obtain a composite pore-forming agent.

[0087] This embodiment discloses a surface-coated modified calcium phosphate microsphere, which is composed of the following components in parts by weight: 66 parts of calcium phosphate ceramic powder, 28 parts of modified bioactive body, 11 parts of composite pore-forming agent, and 4 parts of binder.

[0088] This embodiment discloses a method for preparing surface-coated modified calcium phosphate microspheres, comprising the following steps:

[0089] Step 1: Evenly mix the calcium phosphate ceramic powder and the composite pore-forming agent, then add the binder, and continue mixing and stirring to obtain a mixture;

[0090] Step 2: adding the mixture to the extrusion device of the extrusion spheronization machine, extruding and rolling to obtain calcium phosphate microspheres, and then adding the modified bioactive body to the calcium phosphate microspheres, coating, drying, and calcining to obtain surface-coated modified calcium phosphate microspheres.

[0091] Comparative Example 1: Compared with Example 1, in the process of preparing calcium phosphate microspheres in Comparative Example 1, magnesium phosphate was used instead of the modified bioactive body, and other conditions remained unchanged.

[0092] Comparative Example 2: Compared with Example 1, in the process of preparing calcium phosphate microspheres in Comparative Example 2, starch is used instead of the composite pore-forming agent, and other conditions remain unchanged.

[0093] Experimental Example: The calcium phosphate microspheres prepared in Examples 1-5 and Comparative Examples 1-2 were subjected to performance tests, and the open porosity of the samples was tested using the Archimedes principle. The weight of the sample in the dry state was weighed as G1, and then the sample was immersed in a beaker filled with ethanol, and the air was pumped at a vacuum degree of -98~-96kPa for 1h. Then, the weight of the sample in ethanol was weighed using a specific gravity bottle balance as G2, and then the sample was taken out, and the excess ethanol on the surface was removed with gauze soaked in ethanol. The wet weight of the sample was finally weighed as G3, and the open porosity = [(G3-G2) / (G3-G1)×100%]; the cell counting kit was used to determine the amount of cell proliferation. Under light-proof conditions, a working solution was prepared, and then the complete culture medium in the well plate was removed, 250 μL of a quantitative working solution was added, and then the well plate was placed in a cell culture incubator. After 60 minutes, the well plate was taken out, and then the absorbance OD value of the sample was detected using a multifunctional microplate reader. The specific emission wavelength was 450nm, and the density of the planted cells was 1×10 4 cell / well, the test was carried out after 2, 4 and 7 days of cell culture, and the test results are shown in Table 1:

[0094] Table 1

[0095]

[0096] It can be seen from the test results in Table 1 that the calcium phosphate microspheres prepared in Examples 1-5 of the present invention have excellent porosity and biological activity. By comparing Examples 1-5 with Comparative Examples 1-2, it can be seen that the proliferation of cells on the surface of the samples is very obvious, indicating that each sample has no cytotoxicity and good cell compatibility; by comparing Comparative Example 1 with Examples 1-5, it can be seen that adding modified bioactive bodies can effectively improve the biological activity of calcium phosphate microspheres; by comparing Comparative Example 2 with Examples 1-5, it can be seen that adding a composite pore-forming agent can effectively improve the porosity of calcium phosphate microspheres.

[0097] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0098] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A surface-coated modified calcium phosphate microsphere, characterized in that: The invention is composed of the following components in parts by weight: 60-68 parts of calcium phosphate ceramic powder, 20-32 parts of modified bioactive body, 8-12 parts of composite pore-forming agent and 2-5 parts of binder, wherein the modified bioactive body is prepared from vinyl triethoxysilane, dibutyl butyl phosphate, citric acid, calcium acetate, magnesium sulfate and polyetheretherketone fiber, and the composite pore-forming agent is prepared from octyl dimethyl tertiary amine, epichlorohydrin, hydrolyzed soybean protein and starch.

2. The surface-coated modified calcium phosphate microspheres according to claim 1, characterized in that: The preparation method of the modified biologically active substance comprises the following steps: Q1: Add vinyl triethoxysilane to a container containing a mixed solution of deionized water and ethanol, stir at room temperature, add dibutyl butyl phosphate, stir until completely dissolved, add citric acid, and then add calcium acetate and magnesium sulfate, mix and stir to obtain a mixed solution; Q2: The obtained mixed solution is statically aged to obtain a wet gel, which is then dried, heat treated, and ground to obtain particles; Q3: Add the particles into a container filled with deionized water, disperse them by ultrasonication, then add the polyetheretherketone fiber into the container, shake and stir, filter, and dry to obtain a modified bioactive body.

3. The surface-coated modified calcium phosphate microspheres according to claim 2, characterized in that: In Q1, the dosage ratio of vinyl triethoxysilane, deionized water, ethanol, dibutyl phosphate, citric acid, calcium acetate and magnesium sulfate is (58-62) g: (20-28) mL: (13-18) mL: (22-31) g: (2-5) g: (9-13) g: (11-16) g, the stirring time at room temperature is 30-45 min, and the mixing and stirring time is 4-6 h.

4. The surface-coated modified calcium phosphate microspheres according to claim 2, characterized in that: In the Q2, the static aging temperature is 28-32°C, the aging time is 20-28h, first dried at 60°C for 24h, then dried at 120°C for 24h, the heat treatment process is: heating to 400°C at a heating rate of 2°C / min, keeping warm for 3-5h, then heating to 650°C at a heating rate of 2°C / min, keeping warm for 3-4h, and grinding to a particle size of 60-70μm.

5. The surface-coated modified calcium phosphate microspheres according to claim 2, characterized in that: In the Q3, the dosage ratio of the particulate matter, deionized water and polyetheretherketone fiber is (20-36) g: (10-15) mL: (12-22) g, the ultrasonic dispersion time is 45-60 min, the oscillation stirring time is 3-5 h, the drying temperature is 70-90° C., and the time is 20-24 h.

6. The surface-coated modified calcium phosphate microspheres according to claim 1, characterized in that: The preparation method of the composite pore-forming agent comprises the following steps: S1: Add methanol to a container, slowly add octyl dimethyl tertiary amine under magnetic stirring, then slowly add epichlorohydrin, stir to react, after the reaction is completed, rotary evaporate, then add anhydrous ether, let stand, remove the supernatant, wash, centrifuge, and vacuum dry to obtain compound 1; S2: adding the hydrolyzed soy protein to a container filled with deionized water, stirring until completely dissolved, adjusting the pH, then adding compound 1, heating and stirring to react, continuing to adjust the pH, freeze-drying, washing, freeze-drying again, and grinding to obtain compound 2; S3: Compound 2 is added to distilled water, and after stirring and mixing, starch is added, and the mixture is further stirred and mixed, and dried to obtain a composite pore-forming agent.

7. The surface-coated modified calcium phosphate microspheres according to claim 6, characterized in that: In the S1, the amount ratio of methanol, octyl dimethyl tertiary amine and epichlorohydrin is (60-80) mL: (5.24-8.12) g: (6.16-10.08) g, the stirring reaction temperature is 20-22°C, the reaction time is 10-12h, the standing time is 10-15min, washing is performed with anhydrous ether, the centrifugal speed is 8000-12000rpm, the centrifugal time is 15-20min, and the vacuum drying temperature is 70-85°C for 2-5h.

8. The surface-coated modified calcium phosphate microspheres according to claim 6, characterized in that: In the S2, the average molecular weight of the hydrolyzed soy protein is 3000Da, the amount ratio of the hydrolyzed soy protein, deionized water and compound 1 is (30-45) g: (75-125) mL: (40-55) g, the pH is adjusted to 9.9-10.1 with a sodium hydroxide aqueous solution with a mass fraction of 25wt%, the heating and stirring reaction temperature is 50-55°C, the reaction time is 5-8h, 1mol / L hydrochloric acid is added to adjust the pH to 5-7, and acetone is used for washing; in the S3, the amount ratio of compound 2, distilled water and starch is (8-12) g: (10-15) mL: (20-28) g, and the mixing and stirring time is 30-45min.

9. A method for preparing surface-coated modified calcium phosphate microspheres according to any one of claims 1 to 8, characterized in that: The following steps are involved: Step 1: Evenly mix the calcium phosphate ceramic powder and the composite pore-forming agent, then add the binder, and continue mixing and stirring to obtain a mixture; Step 2: adding the mixture to the extrusion device of the extrusion spheronization machine, extruding and rolling to obtain calcium phosphate microspheres, and then adding the modified bioactive body to the calcium phosphate microspheres, coating, drying, and calcining to obtain surface-coated modified calcium phosphate microspheres.

Images