A surface-coated modified calcium phosphate microsphere and its preparation method

Abstract

The present invention discloses a surface-coated and modified calcium phosphate microsphere and a preparation method thereof, belonging to the technical field of calcium phosphate microsphere preparation. The surface-coated and modified calcium phosphate microsphere 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 former, and 2-5 parts of binder. Among them, the modified bioactive body is prepared from vinyltriethoxysilane, dibutyl butyl phosphate, citric acid, calcium acetate, magnesium sulfate, and polyetheretherketone fiber, and the composite pore former is prepared from octyldimethyl tertiary amine, epichlorohydrin, hydrolyzed soy protein, and starch. The calcium phosphate microsphere prepared by this method has excellent porosity and bioactivity.

Description

Technical Field

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

[0002] With the continuous progress of modern medical technology, people's requirements for bone defect repair materials are increasing day by day. It is expected that the materials can not only effectively fill the bone defect site, but also have good biocompatibility, bioactivity and appropriate 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 clinically. However, although the traditional calcium phosphate ceramic bulk material has good integrity and is convenient for filling, its shape is fixed and it is difficult to accurately match the bone defect site with a complex shape. In contrast, calcium phosphate ceramic particle materials are more suitable for filling irregularly shaped 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 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 beneficial to cell adhesion and migration and the subsequent ingrowth of bone tissue.

[0004] Patent CN113135769B discloses a surface-coated and modified porous calcium phosphate ceramic microsphere and a preparation method and application thereof, including: 1) uniformly mixing calcium phosphate ceramic powder, shaping agent and pore-forming agent to obtain a solid-phase mixture, adding a binder solution to the solid-phase mixture, and uniformly mixing to obtain a plastic wet material; 2) loading the plastic wet material into the extrusion device of an extrusion spheronizer to obtain a strip-shaped cylindrical material, and then pouring the material into the spheronizing device to roll into microspheres; 3) adding bioactive powder to the microspheres in the spheronizing device to obtain microspheres with a surface-coated bioactive substance; 4) drying the microspheres and then placing them in a sintering furnace for high-temperature sintering to obtain a surface-coated and modified porous calcium phosphate ceramic microsphere. The size and porous structure of the microspheres prepared by this method can be adjusted adaptively, and the surface has high bioactivity. However, there is still room for improvement in the porosity and bioactivity of the microspheres prepared by this method. Summary of the Invention

[0005] The purpose of the present invention is to provide a surface-coated and modified calcium phosphate microsphere and a preparation method thereof, which are used to solve the technical problems of poor porosity and bioactivity of calcium phosphate microspheres in the prior art.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention provides a surface-coated and 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 agent, 8-12 parts of composite pore-forming agent, and 2-5 parts of binder. Among them, the modified bioactive agent is prepared from vinyltriethoxysilane, dibutyl butyl phosphate, citric acid, calcium acetate, magnesium sulfate, and polyetheretherketone fiber, and the composite pore-forming agent is prepared from octyldimethyl tertiary amine, epichlorohydrin, hydrolyzed soy protein, and starch.

[0008] Preferably, the preparation method of the modified bioactive agent includes the following steps:

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

[0010] Q2: Let the obtained mixed solution stand for aging to obtain a wet gel, then dry, perform heat treatment, and grind to obtain particulate matter;

[0011] Q3: Add the particulate matter to a container containing deionized water, disperse it ultrasonically, then add polyetheretherketone fiber to the container, shake and stir, filter, and dry to obtain the modified bioactive agent.

[0012] In the above process, first, using deionized water and ethanol as solvents, vinyltriethoxysilane, dibutyl butyl phosphate, calcium acetate, and magnesium sulfate as molecular precursors, and citric acid as a catalyst, particulate matter is prepared by the sol-gel method, and then the particulate matter is compounded with polyetheretherketone fiber to prepare the modified bioactive agent.

[0013] Preferably, in Q1, the dosage ratio of vinyltriethoxysilane, deionized water, ethanol, dibutyl butyl 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 - 28 h. First, it is dried at 60°C for 24 h, and then at 120°C for 24 h. The heat treatment process is as follows: heating at a rate of 2°C / min to 400°C, holding for 3 - 5 h, then heating at a rate of 2°C / min to 650°C, holding for 3 - 4 h, and grinding to a particle size of 60 - 70 μm.

[0015] Preferably, in Q3, the dosage ratio of 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 shaking and 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 includes the following steps:

[0017] S1: Add methanol into a container, slowly add octyldimethyl tertiary amine under magnetic stirring, and then slowly add epichlorohydrin, stir and react. After the reaction is completed, perform rotary evaporation, then add anhydrous ether, let it stand, remove the supernatant, wash, centrifuge, and vacuum dry to obtain Compound 1;

[0018] S2: Add hydrolyzed soy protein into a container containing deionized water, stir until completely dissolved, adjust the pH, then add Compound 1, heat and stir to react, continue to adjust the pH, freeze-dry, wash, freeze-dry again, and grind to obtain Compound 2;

[0019] S3: Add Compound 2 into distilled water, stir and mix, then add starch, continue to mix and stir, and dry to obtain the composite pore-forming agent.

[0020] In the above process, using octyldimethyl tertiary amine and epichlorohydrin as raw materials, Compound 1 is prepared. Subsequently, using hydrolyzed soy protein as the raw material, it undergoes a quaternization reaction with Compound 1 to obtain Compound 2, and then Compound 2 is mixed with starch to prepare the composite pore-forming agent.

[0021] Preferably, in S1, the dosage ratio of methanol, octyldimethyl 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 - 12 h, the standing time is 10 - 15 min, wash with anhydrous ether, the centrifugation speed is 8000 - 12000 rpm, the centrifugation time is 15 - 20 min, and the vacuum drying temperature is 70 - 85°C, and the time is 2 - 5 h.

[0022] Preferably, in S2, the average molecular weight of the hydrolyzed soy protein is 3000 Da, and 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 25 wt% sodium hydroxide aqueous solution, the heating and stirring reaction temperature is 50 - 55 °C, the reaction time is 5 - 8 h, the pH is adjusted to 5 - 7 with 1 mol / L hydrochloric acid, and washing is carried out 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 - 45 min.

[0023] Preferably, a method for preparing a surface-coated and modified calcium phosphate microsphere includes the following steps:

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

[0025] Step 2: Add the mixture to the extrusion device of an extrusion and rounding machine, extrude and roll to obtain calcium phosphate microspheres, then add the modified bioactive body to the calcium phosphate microspheres, coat, dry and calcine to obtain a surface-coated and modified calcium phosphate microsphere.

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

[0027] 1. The present invention first uses vinyltriethoxysilane, dibutyl butylphosphonate, citric acid, calcium acetate, magnesium sulfate and polyetheretherketone fibers as raw materials to prepare a modified bioactive body. Subsequently, octyldimethyl tertiary amine, epichlorohydrin, hydrolyzed soy protein and starch are used as raw materials to prepare a composite pore-forming agent. Adding the modified bioactive body and the composite pore-forming agent to the preparation process of calcium phosphate microspheres can effectively improve their porosity and bioactivity.

[0028] 2. Adding the prepared modified bioactive body to the calcium phosphate microspheres can effectively improve their bioactivity. The silicate, phosphate, calcium salt and magnesium salt contained in the modified bioactive body can promote the increase of active sites on the surface of the microspheres and improve their bioactivity. 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. Moreover, the addition of the modified bioactive body will improve the drug loading capacity of the calcium phosphate microspheres, enhance the drug release performance, and achieve continuous 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 endow it with stronger osteoconduction.

[0029] 3. The composite pore-forming agent prepared in the present invention is added to the calcium phosphate microspheres, which can effectively increase their porosity. Compound 2 has excellent surface activity, which can effectively reduce the surface tension of the solution, improve the dispersibility and stability of starch granules in the calcium phosphate powder, and at the same time, the quaternary ammonium salt group contained in Compound 2 has good antibacterial and biocompatible properties, which helps to improve the biological properties of the calcium phosphate material. After the starch granules used as the pore-forming agent are uniformly dispersed in the calcium phosphate powder, through sintering treatment, the voids left by the combustion of the starch form a porous structure. The surface activity of Compound 2 further optimizes the dispersion state of the starch granules, precisely controls the size and distribution of the pore diameter, reduces pore blockage, significantly increases the porosity of the calcium phosphate material after sintering, and at the same time, the presence of Compound 2 can also promote the compatibility of the calcium phosphate material with biological tissues, which helps cell adhesion and growth. Detailed implementation manners

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Apparently, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0031] Example 1: This example discloses a preparation method of a modified bioactive body, including the following steps:

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

[0033] Q2: Let the obtained mixed solution age statically at 28 °C for 24 h to obtain a wet gel. First, dry it at 60 °C for 24 h, then dry it at 120 °C for 24 h, heat it to 400 °C at a heating rate of 2 °C / min, hold for 4 h, then heat it to 650 °C at a heating rate of 2 °C / min, hold for 3 h, and grind it to a particle size of 60 μm to obtain particulate matter;

[0034] Q3: Add 28 g of the particulate matter to a container containing 12.5 mL of deionized water, ultrasonically disperse for 60 min, then add 17 g of polyether ether ketone fibers to the container, shake and stir for 4 h, filter, and dry at 80 °C for 24 h to obtain the modified bioactive body.

[0035] This embodiment discloses a preparation method of a composite pore former, comprising the following steps:

[0036] S1: Add 70 mL of methanol into a container, slowly add 6.32 g of octyldimethyl tertiary amine under magnetic stirring, and then slowly add 8.12 g of epichlorohydrin. Stir and react at 20 °C for 12 h. After the reaction, perform rotary evaporation, then add anhydrous ether, let it stand for 15 min, remove the supernatant, wash with anhydrous ether, centrifuge at 12000 rpm for 20 min, and vacuum dry at 85 °C for 4 h to obtain Compound 1;

[0037] S2: Add 37.5 g of hydrolyzed soy protein with an average molecular weight of 3000 Da into a container containing 100 mL of deionized water, stir until completely dissolved, adjust the pH to 10 with a 25 wt% sodium hydroxide aqueous solution, then add 47.5 g of Compound 1, stir and react at 55 °C for 6 h, add 1 mol / L hydrochloric acid to continue adjusting the pH to 6, freeze-dry, wash with acetone, freeze-dry again, and grind to obtain Compound 2;

[0038] S3: Add 10 g of Compound 2 into 12.5 mL of distilled water, stir and mix, then add 24 g of starch, continue to mix and stir for 45 min, and dry to obtain the composite pore former.

[0039] This embodiment discloses a surface-coated and 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 former, and 3.5 parts of binder.

[0040] This embodiment discloses a preparation method of a surface-coated and modified calcium phosphate microsphere, comprising the following steps:

[0041] Step 1: Mix the calcium phosphate ceramic powder and the composite pore former evenly, then add the binder, and continue to mix and stir to obtain a mixture;

[0042] Step 2: Add the mixture into the extrusion device of an extrusion and spheronization machine, extrude and roll to obtain calcium phosphate microspheres, then add the modified bioactive body into the calcium phosphate microspheres, coat, dry, and calcine to obtain a surface-coated and modified calcium phosphate microsphere.

[0043] Example 2: This embodiment discloses a preparation method of a modified bioactive body, comprising the following steps:

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

[0045] Q2: The obtained mixed solution is left to age statically at 28 °C for 24 h to obtain a wet gel. First, it is dried at 60 °C for 24 h, then at 120 °C for 24 h. It is heated to 400 °C at a heating rate of 2 °C / min and kept at this temperature for reaction for 4 h. Then it is heated to 650 °C at a heating rate of 2 °C / min and kept at this temperature for reaction for 3 h. It is ground until the particle size is 60 μm to obtain particulate matter;

[0046] Q3: Add 20 g of the particulate matter to a container containing 10 mL of deionized water, ultrasonically disperse for 60 min, then add 12 g of polyetheretherketone fibers to the container, shake and stir for 4 h, filter, and dry at 80 °C for 24 h to obtain a modified bioactive body.

[0047] This example discloses a preparation method of a composite pore-forming agent, comprising the following steps:

[0048] S1: Add 60 mL of methanol to a container, slowly add 5.24 g of octyldimethyl tertiary amine under magnetic stirring, then slowly add 6.16 g of epichlorohydrin, stir and react at 20 °C for 12 h. After the reaction, perform rotary evaporation, then add anhydrous ether, let it stand for 15 min, remove the supernatant, wash with anhydrous ether, centrifuge at 12000 rpm for 20 min, and vacuum dry at 85 °C for 4 h to obtain Compound 1;

[0049] S2: Add 30 g of hydrolyzed soy protein with an average molecular weight of 3000 Da to a container containing 75 mL of deionized water, stir until completely dissolved, adjust the pH to 10 with a 25 wt% aqueous sodium hydroxide solution, then add 40 g of Compound 1, stir and react at 55 °C for 6 h, add 1 mol / L hydrochloric acid to continue adjusting the pH to 6, freeze-dry, wash with acetone, freeze-dry again, and grind to obtain Compound 2;

[0050] S3: Add 8 g of Compound 2 to 10 mL of distilled water, stir and mix, then add 20 g of starch, continue to mix and stir for 45 min, and dry to obtain the composite pore-forming agent.

[0051] This example discloses a surface-coated and 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 example discloses a preparation method of a surface-coated and modified calcium phosphate microsphere, comprising the following steps:

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

[0054] Step 2: Add the mixture into the extrusion device of an extrusion spheronizer, extrude and roll to obtain calcium phosphate microspheres. Then add the modified bioactive body into the calcium phosphate microspheres, coat, dry, and calcine to obtain a calcium phosphate microsphere with a surface-coated modification.

[0055] Example 3: This example discloses a preparation method of a modified bioactive body, including the following steps:

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

[0057] Q2: Let the obtained mixed solution stand and age at 28 °C for 24 h to obtain a wet gel. First, dry it at 60 °C for 24 h, then dry it at 120 °C for 24 h. Heat it to 400 °C at a heating rate of 2 °C / min, hold the temperature for reaction for 4 h, then heat it to 650 °C at a heating rate of 2 °C / min, hold the temperature for reaction for 3 h, and grind it to a particle size of 60 μm to obtain particulate matter;

[0058] Q3: Add 36 g of particulate matter into a container containing 15 mL of deionized water, ultrasonically disperse for 60 min, then add 22 g of polyetheretherketone fibers into the container, oscillate and stir for 4 h, filter, and dry at 80 °C for 24 h to obtain a modified bioactive body.

[0059] This example discloses a preparation method of a composite pore former, including the following steps:

[0060] S1: Add 80 mL of methanol into a container, slowly add 8.12 g of octyldimethyl tertiary amine under magnetic stirring, then slowly add 10.08 g of epichlorohydrin, stir and react at 20 °C for 12 h. After the reaction ends, perform rotary evaporation, then add anhydrous ether, let it stand for 15 min, remove the supernatant, wash with anhydrous ether, centrifuge at 12000 rpm for 20 min, and vacuum dry at 85 °C for 4 h to obtain Compound 1;

[0061] S2: Add 45 g of hydrolyzed soy protein with an average molecular weight of 3000 Da into a container containing 125 mL of deionized water, stir until completely dissolved, adjust the pH = 10 with a 25 wt% sodium hydroxide aqueous solution, then add 55 g of Compound 1, stir and react at 55 °C for 6 h, add 1 mol / L hydrochloric acid to further adjust the pH = 6, freeze-dry, wash with acetone, freeze-dry again, and grind to obtain Compound 2;

[0062] S3: Add 12 g of Compound 2 to 15 mL of distilled water. After stirring and mixing, add 28 g of starch, continue to mix and stir for 45 min, and then dry to obtain a composite pore-forming agent.

[0063] This example discloses a surface-coated and 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 substance, 12 parts of composite pore-forming agent, and 5 parts of binder.

[0064] This example discloses a preparation method of a surface-coated and modified calcium phosphate microsphere, including the following steps:

[0065] Step 1: Mix the calcium phosphate ceramic powder and the composite pore-forming agent evenly, then add the binder, and continue to mix and stir to obtain a mixture.

[0066] Step 2: Add the mixture to the extrusion device of an extrusion and spheronization machine, extrude and roll to obtain calcium phosphate microspheres. Then add the modified bioactive substance to the calcium phosphate microspheres, coat, dry, and calcine to obtain a surface-coated and modified calcium phosphate microsphere.

[0067] Example 4: This example discloses a preparation method of a modified bioactive substance, including the following steps:

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

[0069] Q2: Let the obtained mixed solution stand and age at 28 °C for 24 h to obtain a wet gel. First, dry it at 60 °C for 24 h, then dry it at 120 °C for 24 h. Heat it to 400 °C at a heating rate of 2 °C / min, hold the temperature for reaction for 4 h, then heat it to 650 °C at a heating rate of 2 °C / min, hold the temperature for reaction for 3 h, and grind it to a particle size of 60 μm to obtain particulate matter.

[0070] Q3: Add 24 g of the particulate matter to a container containing 11 mL of deionized water, ultrasonically disperse it for 60 min, then add 14 g of polyetheretherketone fibers to the container, shake and stir for 4 h, filter, and dry at 80 °C for 24 h to obtain a modified bioactive substance.

[0071] This example discloses a preparation method of a composite pore-forming agent, including the following steps:

[0072] S1: Add 65 mL of methanol into a container. Slowly add 5.87 g of octyldimethyl tertiary amine under magnetic stirring, and then slowly add 7.23 g of epichlorohydrin. Stir and react at 20 °C for 12 h. After the reaction, perform rotary evaporation, then add anhydrous ether, let it stand for 15 min, remove the supernatant, wash with anhydrous ether, centrifuge at 12000 rpm for 20 min, and dry in vacuum at 85 °C for 4 h to obtain Compound 1;

[0073] S2: Add 32 g of hydrolyzed soy protein with an average molecular weight of 3000 Da into a container containing 85 mL of deionized water, stir until completely dissolved, adjust the pH to 10 with a 25 wt% aqueous sodium hydroxide solution, then add 42 g of Compound 1, stir and react at 55 °C for 6 h, add 1 mol / L hydrochloric acid to continue adjusting the pH to 6, freeze-dry, wash with acetone, freeze-dry again, and grind to obtain Compound 2;

[0074] S3: Add 9 g of Compound 2 into 11 mL of distilled water, stir and mix, then add 22 g of starch, continue to mix and stir for 45 min, and dry to obtain a composite pore-forming agent.

[0075] This example discloses a surface-coated and 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 substance, 9 parts of composite pore-forming agent, and 3 parts of binder.

[0076] This example discloses a preparation method of a surface-coated and modified calcium phosphate microsphere, including the following steps:

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

[0078] Step 2: Add the mixture into the extrusion device of an extrusion and spheronization machine, extrude and roll to obtain calcium phosphate microspheres, then add the modified bioactive substance into the calcium phosphate microspheres, coat, dry, and calcine to obtain a surface-coated and modified calcium phosphate microsphere.

[0079] Example 5: This example discloses a preparation method of a modified bioactive substance, including the following steps:

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

[0081] Q2: The obtained mixed solution was aged statically at 28°C for 24 h to obtain a wet gel. First, it was dried at 60°C for 24 h, and then at 120°C for 24 h. It was heated to 400°C at a heating rate of 2°C / min and held for 4 h, and then heated to 650°C at a heating rate of 2°C / min and held for 3 h, and ground to a particle size of 60 μm to obtain particulate matter;

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

[0083] This example discloses a preparation method of a composite pore former, including the following steps:

[0084] S1: 75 mL of methanol was added to a container, and 7.15 g of octyldimethyl tertiary amine was slowly added under magnetic stirring, and then 9.05 g of epichlorohydrin was slowly added. The reaction was stirred at 20°C for 12 h. After the reaction ended, rotary evaporation was carried out, then anhydrous ether was added, allowed to stand for 15 min, the supernatant was removed, washed with anhydrous ether, 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 containing 105 mL of deionized water and stirred until completely dissolved. The pH was adjusted to 10 with a 25 wt% aqueous sodium hydroxide solution, then 53 g of Compound 1 was added, and the reaction was stirred at 55°C for 6 h. 1 mol / L hydrochloric acid was added to continue adjusting the pH to 6, 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, stirred and mixed, then 26 g of starch was added, and the mixture was continuously stirred for 45 min and dried to obtain a composite pore former.

[0087] This example discloses a surface-coated and 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 former, and 4 parts of binder.

[0088] This example discloses a preparation method of a surface-coated and modified calcium phosphate microsphere, including the following steps:

[0089] Step 1: The calcium phosphate ceramic powder and the composite pore former were mixed evenly, and then the binder was added, and the mixture was continuously stirred to obtain a mixture;

[0090] Step 2: Add the mixture into the extrusion device of an extrusion spheronizer, extrude and roll to obtain calcium phosphate microspheres. Then add the modified bioactive agent into the calcium phosphate microspheres, coat, dry and calcine to obtain a kind of calcium phosphate microspheres with surface-coated modification.

[0091] Comparative Example 1: Compared with Example 1, in the process of preparing calcium phosphate microspheres in Comparative Example 1, magnesium phosphate was used to replace the modified bioactive agent, 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 was used to replace the composite pore-forming agent, and other conditions remained unchanged.

[0093] Experimental Example: Perform performance tests on the calcium phosphate microspheres prepared in Examples 1-5 and Comparative Examples 1-2. Use the Archimedes principle to test the open porosity of the samples. Weigh the weight of the sample in the dry state as G1. Then immerse the sample in a beaker filled with ethanol, evacuate at a vacuum degree of -98~-96 kPa for 1 h, and then use a pycnometer balance to weigh the weight of the sample in ethanol as G2. Then take out the sample and use a gauze soaked with ethanol to remove the excess ethanol on the surface. Finally, weigh the wet weight of the sample as G3. The open porosity = [(G3 - G2) / (G3 - G1)×100%]; Use a cell counting kit to determine the cell proliferation amount. Under light-shielded conditions, prepare the working solution. Then remove the complete medium in the well plate, add 250 μL of the quantitative working solution, and then place the well plate in a cell culture incubator. Take out the well plate after 60 min, and then use a multifunctional microplate reader to detect the absorbance OD value of the sample. The specific emission wavelength is 450 nm, where the seeding cell density is 1×10 4 cells / well, and the tests are carried out after 2, 4, and 7 d of cell culture. 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 bioactivity. 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 the modified bioactive agent can effectively improve the bioactivity of the calcium phosphate microspheres; by comparing Comparative Example 2 with Examples 1-5, it can be seen that adding the composite pore-forming agent can effectively improve the porosity of the calcium phosphate microspheres.

[0097] As described above, it is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent replacements or changes should be covered within the protection scope of the present invention.

[0098] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the present invention to only the specific embodiments. Obviously, many modifications and changes can be made according to the content of this specification. These embodiments are selected and specifically described in this specification to better explain the principle and practical application of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited 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.

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