AU2020244514B2

AU2020244514B2 - Tricalcium phosphate material doped with Mg and Zn and preparation method thereof, and 3D printing ceramic slurry and preparation method thereof

Info

Publication number: AU2020244514B2
Application number: AU2020244514A
Authority: AU
Inventors: Yun Bai; Lei Cao; Rui Yang; Xing Zhang
Original assignee: Institute of Metal Research of CAS
Current assignee: Institute of Metal Research of CAS
Priority date: 2020-06-11
Filing date: 2020-09-30
Publication date: 2022-07-21
Anticipated expiration: 2040-09-30
Also published as: AU2020244514A1; CN111635224A; CN111635224B

Abstract

The present disclosure relates to a tricalcium phosphate material doped with Mg and Zn and a preparation method thereof, and 3D printing ceramic slurry and a 5 preparation method thereof. The present disclosure mainly employs the following technical solutions. In the tricalcium phosphate material doped with Mg and Zn, the number of moles of Mg is ni, the number of moles of Zn is n2, and the total number of moles of Ca, Mg and Zn is n3, where n1/n3 is 10% to 15%, and n2/n3 is 5% to 10%. The 3D printing ceramic slurry comprises ceramic powder and an organic resin solution, 0 wherein the ceramic power is the tricalcium phosphate material doped with Mg and Zn. In the present disclosure, the bioactivity of the tricalcium phosphate material is mainly improved by doping Mg and Zn. By using the tricalcium phosphate material doped with Mg and Zn as the ceramic powder in the 3D printing ceramic slurry, the bioactivity and compactness of biologic ceramics prepared by 3D printing can be improved. 5 16564100_1 (GHMatters) P114439.AU

Description

TRICALCIUM PHOSPHATE MATERIAL DOPED WITH MG AND ZN AND PREPARATION METHOD THEREOF, AND 3D PRINTING CERAMIC SLURRY AND PREPARATION METHOD THEREOF

The present disclosure claims priority to Chinese Patent Application No. 202010529753.7 filed to the CNIPA on June 11, 2020 and titled TRICALCIUM PHOSPHATE MATERIAL DOPED WITH MG AND ZN AND PREPARATION METHOD THEREOF, AND 3D PRINTING CERAMIC SLURRY AND PREPARATION METHOD THEREOF, the disclosure of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD The present disclosure relates to the technical field of biological ceramics, and in particular to a tricalcium phosphate material doped with Mg and Zn and a preparation method thereof, and 3D printing ceramic slurry and a preparation method thereof.

BACKGROUND OF THE PRESENT INVENTION Bone defect repair is one of common clinical symptoms in orthopedics. In China, there are about 3 million patients with bone defect or bone injury caused by various accidents and diseases every year. Small-area bone defects can be cured by the regeneration function of the body itself. However, large-area bone defects cannot be repaired by themselves, and may cause "nonunion" if they are not treated. Therefore, it is necessary to implant artificial bone materials to assist in repairing and healing bone tissues. Artificial bone materials (such as tricalcium phosphate ceramics, bone cement and high-molecular polymers) have been more and more widely applied in clinical bone defect repair. Tricalcium phosphate is an ideal third-generation biodegradable biological ceramic material since it is good in biocompatibility and eventually degraded after being implanted into the body.

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Multifunctional ceramics with complex structure and high precision can be

prepared by 3D printing, so 3D printing can be used to prepare biological ceramics (such as artificial bones). The photocurable ceramic 3D printing has promising

application prospect due to its advantages of high precision, flexible process and the

like. Ceramic slurry is the key of the photocurable ceramic 3D printing.

At present, the ceramic powder in the 3D printing ceramic slurry is conventional materials such as calcium phosphate (undoped), alumina and zirconia, and the

ceramic powder has a particle size in submicron (0.7 pm to 1.5 pm). However, the

inventor(s) of the present disclosure has (have) found that the ceramic powder used in the existing 3D printing has at least the following technical problems: (1) the

conventional materials such as calcium phosphate, alumina and zirconia are low in

bioactivity, and the biological ceramics prepared from these materials as ceramic powder for 3D printing are also low in bioactivity and cannot promote bone growth, so

that the bone growth is too slow; and, (2) the methods for preparing nano-ceramic

powder are complex and high in energy consumption.

SUMMARY OF THE PRESENT INVENTION In view of this, the present disclosure provides a tricalcium phosphate material

doped with Mg and Zn and a preparation method thereof, and 3D printing ceramic slurry and a preparation method thereof, in order to improve the bioactivity of the

tricalcium phosphate material by doping Mg and Zn and prepare biological ceramics

(such as artificial bones) with good bioactivity.

For this purpose, the present disclosure mainly provides the following technical solutions. In one aspect, there is provided a method for preparing a tricalcium phosphate

material doped with Mg and Zn, wherein, in the tricalcium phosphate material doped with Mg and Zn, the number of moles of Mg is ni, the number of moles of Zn is n2, and

the total number of moles of Ca, Mg and Zn is n3, where n1/n3 is 10% to 15%, and

18805842_1 (GHMatters) P114439.AU n2/n3 is 5% to 10%; wherein the tricalcium phosphate material doped with Mg and Zn has a particle size of 30 nm to 150 nm; and the method for preparing the tricalcium phosphate material doped with Mg and Zn comprises steps of: 1) reacting a first solution containing magnesium ions, zinc ions and calcium ions with a second solution containing phosphate ions at a set temperature for a set time to obtain a reaction product; wherein the set temperature is 80°C to 160°C; wherein, in the first solution, the number of moles of Mg is ni, the number of moles of Zn is n2, and the total number of moles of Ca, Mg and Zn is n3, where n1/n3 is 10% to 15%, and n2/n3 is 5% to 10%; and 2) washing and freeze-drying or baking the reaction product to obtain the tricalcium phosphate material doped with Mg and Zn. In some embodiments, in the step 1): the set time is 6 h to 24 h. In some embodiments, in the step 1): the first solution is a mixed solution of calcium salt, magnesium salt and zinc salt; in some embodiments, the first solution is a mixed solution of calcium nitrate, magnesium nitrate and zinc nitrate; and, further in some embodiments, in the first solution, the calcium nitrate has a concentration of 100 to 200 g/L, the magnesium nitrate has a concentration of 10 to 40 g/L, and the zinc nitrate has a concentration of 10 to 30 g/L. In some embodiments, in the step 1): the second solution is an ammonium dihydrogen phosphate solution with a pH value adjusted by ammonia water; in some embodiments, ammonium dihydrogen phosphate has a concentration of 25 to 100 g/L; in some embodiments, the second solution has a pH value of 8.5 to 9.5; and, in some embodiments, the ammonia water has a mass fraction of 20wt% to 30wt%, preferably 25wt%. In some embodiments, in the step 1): the volume ratio of the first solution to the second solution is (1:1.2) to (1.2:1), preferably (1:1.1) to (1.1:1), further preferably 1:1; and/or, in the second solution, the number of moles of phosphorus is n4, where n3/n4 is 1.45 to 1.65, preferably 1.5. In some embodiments, the step 1) is specifically: adding the first solution into the

18805842_1 (GHMatters) P114439.AU second solution, and reacting, while stirring, the first solution and the second solution at the set temperature for the set time. In still another aspect, there is provided a 3D printing ceramic slurry, wherein ceramic powder in the 3D printing ceramic slurry is the tricalcium phosphate material doped with Mg and Zn described above; wherein the tricalcium phosphate material doped with Mg and Zn is made by the method described above. In some embodiments, the 3D printing ceramic slurry comprises ceramic powder and an organic resin solution, the ceramic powder having a volume fraction of 30% to

60% and the organic resin having a volume fraction of 40% to 70%; and, in some embodiments, the organic resin solution includes: a photocurable resin having a

volume fraction of 92% to 98.7%, a photoinitiator having a volume fraction of 0.1% to

1%, a leveling agent having a volume fraction of 0.1% to 1%, an antifoaming agent having a volume fraction of 0.1% to 1%, and a dispersant having a volume fraction of

1% to 5%.

In yet another aspect, a method for preparing the 3D printing ceramic slurry as described above is provided, comprising steps of: adding ceramic powder into an organic resin solution, and grinding to obtain the 3D printing ceramic slurry, wherein, the grinding lasts for 5 h to 30 h.

In some embodiments, the grinding lasts for 10 h to 25 h. Compared with the prior art, the tricalcium phosphate material doped with Mg and

Zn and preparation method thereof and the 3D printing ceramic slurry and preparation

method thereof provided by the present disclosure have at least the following

beneficial effects. On one hand, in the tricalcium phosphate material doped with Mg and Zn provided in the embodiments of the present disclosure, Mg and Zn are doped into the

tricalcium phosphate material, the doping amount of Mg is controlled to be 10% to 15%, and the doping amount of Zn is controlled to be 5% to 10%. Thus, the formation

18805842_1 (GHMatters) P114439.AU of hydroxyapatite during crystallization can be inhibited, and the tricalcium phosphate material doped with Mg and Zn has good bioactivity due to the synergistic action of Mg and Zn. Accordingly, the tricalcium phosphate material doped with Mg and Zn can be used to prepare biological ceramics with good bioactivity, such as artificial bones, and can promote the bone growth of the human body. Further, the tricalcium phosphate material doped with Mg and Zn provided in the embodiments of the present disclosure has a particle size of 30 nm to 150 nm. By using the tricalcium phosphate material doped with Mg and Zn in this particle size as powder of photocurable 3D printing ceramic slurry, biological ceramics with good compactness is finally printed. The method for preparing a tricalcium phosphate material doped with Mg and Zn provided in the embodiments of the present disclosure has low reaction temperature and does not use any organic solvent during the preparation process. Therefore, the method for preparing a tricalcium phosphate material doped with Mg and Zn is low in energy consumption, low in cost and pollution-free. Moreover, by controlling the reaction conditions, the tricalcium phosphate material doped with Mg and Zn having a particle size of 30 nm to 150 nm can be prepared. On the other hand, in the 3D printing ceramic slurry and preparation method thereof provided in the embodiments of the present disclosure, by using the tricalcium phosphate material doped with Mg and Zn as ceramic powder to prepare the 3D printing ceramic slurry, biological ceramics obtained by 3D printing have good bioactivity and good compactness. The foregoing description merely shows the overview of the technical solutions of the present disclosure. To understand the technical means of the present disclosure more clearly and implement the present disclosure according to the contents in this specification, the preferred embodiments of the present disclosure will be described below in detail with reference to the accompanying drawings.

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BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a morphological diagram of the tricalcium phosphate material doped with Mg and Zn prepared in Embodiment 1; Fig. 2 is a morphological diagram of the tricalcium phosphate material doped with Mg and Zn prepared in Embodiment 2; Fig. 3 is the XRD spectrum of nano-tricalcium phosphate doped with different contents of Mg and Zn, where the curve (a) in Fig. 3 is the XRD spectrum of the tricalcium phosphate material doped with Mg and Zn prepared in Embodiment 1, the curve (b) is the XRD spectrum of the tricalcium phosphate material doped with Mg and Zn prepared in Embodiment 2, the curve (c) is the XRD spectrum of the tricalcium phosphate material doped with Mg and Zn prepared in Embodiment 3, and the curve (d) is the XRD spectrum of the tricalcium phosphate material doped with Mg and Zn prepared in Embodiment 4; Fig. 4 is the infrared spectrum of nano-tricalcium phosphate doped with different contents of Mg and Zn, where the curve (a) in Fig. 4 is the infrared spectrum of the tricalcium phosphate material doped with Mg and Zn prepared in Embodiment 1, the curve (b) is the infrared spectrum of the tricalcium phosphate material doped with Mg and Zn prepared in Embodiment 2, the curve (c) is the infrared spectrum of the tricalcium phosphate material doped with Mg and Zn prepared in Embodiment 3, and the curve (d) is the infrared spectrum of the tricalcium phosphate material doped with Mg and Zn prepared in Embodiment 4; Fig. 5 shows the surface cell adhesion morphology (see Fig. 5(a)) and the surface EDS energy spectrum (see Fig. 5(b)) after a Mg-Zn tricalcium phosphate coating is prepared on the surface of titanium alloy (Ti-6Al-4V) by plasma spraying; and Fig. 6 is a morphological diagram of ceramics after photocurable 3D printing ceramic slurry (with a solid content of 50%) prepared by using the tricalcium phosphate material doped with Mg and Zn prepared in Embodiment 1 as ceramic

16564100_1 (GHMatters) P114439.AU powder is 3D-printed and sintered, where Fig. 6(a) is the morphology of a scaffold with a curved surface structure, Fig. 6(b) is the sectional morphology of the scaffold observed by scanning electron microscopy, and Fig. 6(c) is the partially enlarged morphology of the region in the dashed box in Fig. 6(b).

DETAILED DESCRIPTION OF THE PRESENT INVENTION To further explain the technical means used to achieve the intended objective and the effects thereof in the present disclosure, the specific implementations, structures, features and effects thereof of the present disclosure will be described below in detail by preferred embodiments with reference to the accompanying drawings. In the following description, terms "one embodiment" or "embodiments" do not necessarily refer to a same embodiment. In addition, particular features, structures or characteristics in one or more embodiments may be combined in any proper way. In the prior art, the ceramic powder in the ceramic slurry for photocurable 3D printing is conventional materials such as calcium phosphate, alumina and zirconia, and the ceramic powder has a particle size in submicron (0.7 pm to 1.5 pm), so that the biological ceramics obtained by 3D printing have the technical problems of low bioactivity and low compactness. Accordingly, the inventor(s) of the present disclosure prepares a doped tricalcium phosphate material as photocurable 3D printing ceramic slurry to improve the bioactivity of the printed biological ceramics, and further adjust the particle size of the prepared tricalcium phosphate material by a preparation method so as to improve the compactness of the printed biological ceramics. Further, there are many researches on doped tricalcium phosphate materials in the prior art. However, the inventor(s) of the present disclosure has (have) found that there are still some problems in the existing researches. On one hand, the synergistic action between doped metal ions and between metal ions and calcium ions cannot be

16564100_1 (GHMatters) P114439.AU fully realized, so that the bioactivity cannot be improved effectively. On the other hand, the existing methods for preparing element-doped nano-tricalcium phosphate mainly include calcination, preparation using a bionic solution, mechanical stirring and flame spraying. In most of the methods, high-temperature heating, organic solvents or the like are used, so the cost for preparing nano-tricalcium phosphate is increased, the energy consumption is high, and it is disadvantageous for large-scale production. To overcome the technical problems mentioned above, embodiments of the present disclosure provide a tricalcium phosphate material doped with Mg and Zn and a preparation method thereof, and 3D printing ceramic slurry and a preparation method thereof. Specifically: In one aspect, an embodiment of the present disclosure provides a tricalcium phosphate material doped with Mg and Zn, wherein, in the tricalcium phosphate material doped with Mg and Zn, the number of moles of Mg is ni, the number of moles of Zn is n2, and the total number of moles of Ca, Mg and Zn is n3, where n1/n3 is 10% to 15% (i.e., the doping amount of Mg or the doping mole percentage of Mg), and n2/n3 is 5% to 10% (i.e., the doping amount of Zn or the doping mole percentage of Zn). Hence, in the present disclosure, by doping magnesium and zinc into tricalcium phosphate and controlling the doping amount of Mg to be 10% to 15% and the doping amount of Zn to be 5% to 10%, the formation of hydroxyapatite during crystallization can be inhibited, and the tricalcium phosphate material doped with Mg and Zn has good bioactivity due to the synergistic action of Mg and Zn. Accordingly, the tricalcium phosphate material doped with Mg and Zn can be used to prepare biological ceramics with good bioactivity, such as artificial bones, and can promote the bone growth of the human body. In some embodiments, the tricalcium phosphate material doped with Mg and Zn provided in the embodiment of the present disclosure has a particle size of 30 nm to 150 nm. By using the tricalcium phosphate material doped with Mg and Zn in this

16564100_1 (GHMatters) P114439.AU particle size as powder of photocurable 3D printing ceramic slurry, the compactness of biological ceramics obtained by 3D printing can be improved. In another aspect, with regard to the tricalcium phosphate material doped with Mg and Zn, to reduce the energy consumption for preparation, reduce the preparation cost and avoid the use of organic solvents, an embodiment of the present disclosure designs the following preparation scheme. Preparation of a first solution: calcium nitrate, magnesium nitrate and zinc nitrate are dissolved in deionized water obtain a first solution. In some embodiments, in the first solution, the calcium nitrate solution has a concentration of 100 to 200 g/L, the magnesium nitrate solution has a concentration of 10 to 40 g/L, and the zinc nitrate solution has a concentration of 10 to 30 g/L. In the first solution, the mole percentage of Ca, the mole percentage of Mg and the mole percentage of Zn satisfy the following conditions: Mg/(Ca+Mg+Zn)=10%-15%, and Zn/(Ca+Mg+Zn)=5%-10%. Preparation of a second solution: diammonium hydrogen phosphate is dissolved in deionized water and then adjusted with 25wt% of ammonia water until the pH value is 8.5 to 9.5, to obtain a second solution. In some embodiments, the diammonium hydrogen phosphate solution in the second solution has a concentration of 25 to 100 g/L, the volume of the second solution is equal to that of the first solution, and the number of moles of phosphorous satisfies the following condition: (Ca+Mg+Zn)/P=1.5. Mixed reaction: the first solution is quickly added into the second solution, and the system is fully stirred, heated and kept for several hours (reacted at a set temperature for a set time), filtered and washed (washed with deionized water and alcohol for three times, respectively), and freeze-dried or baked to obtain the tricalcium phosphate material doped with Mg and Zn (i.e., a nano-p-TCP material containing Mg and Zn). In some embodiments, the set temperature is 80°C to 160°C, preferably 80°C to 150°C; and, the reaction lasts for 6 h to 24 h. By controlling the reaction temperature and the reaction time, the particle size of the prepared

16564100_1 (GHMatters) P114439.AU phosphate material doped with Mg and Zn can be controlled. It can be known from the preparation process that the preparation method provided in this embodiment of the present disclosure has low reaction temperature and does not use any organic solvent, so the preparation method is low in energy consumption, low in cost and pollution-free. In still another aspect, an embodiment of the present disclosure provides 3D printing ceramic slurry (i.e., photocurable 3D printing ceramic slurry). The 3D printing ceramic slurry includes ceramic powder (which is the tricalcium phosphate material doped with Mg and Zn) and an organic resin solution, wherein the ceramic powder has a volume fraction of 30% to 50% and the organic resin has a volume fraction of 50% to 70%. The organic resin solution includes: a photocurable resin having a volume fraction of 92% to 98.7%, a photoinitiator having a volume fraction of 0.1% to 1%, a leveling agent having a volume fraction of 0.1% to 1%, an antifoaming agent having a volume fraction of 0.1% to 1%, and a dispersant having a volume fraction of 1% to 5%. In addition, a method for preparing the 3D printing ceramic slurry is provided, including steps of: adding ceramic powder into an organic resin solution, and grinding to obtain the 3D printing ceramic slurry. In some embodiments, the grinding lasts for 5 h to 30 h, preferably 10 h to 25 h. The following detailed description will be given by specific experimental embodiments. Main raw materials used in the following experimental embodiments include: Ca(N03)2 (analytically pure), Mg(N03)2 (analytically pure), Zn(N03)2 (analytically pure), (NH4)2HP04 (analytically pure) and NH3-H20 (analytically pure). Embodiment 1 In this embodiment, a tricalcium phosphate material (p-TCP material) doped with Mg and Zn was prepared by the following specific steps. 191.1 g of Ca(N03)2-4H20, 24.4 g of Mg(N03)2-6H20 and 14.2 g of

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Zn(N03)2-6H20 were dissolved in 1 L of deionized water and then stirred uniformly to obtain a first solution. 83.8 g of (NH4)2HP04 was dissolved in 1 L of deionized water, then stirred uniformly, and added dropwise with ammonia water having a mass fraction of 25wt% until pH was adjusted to 9.5, to obtain a second solution. The prepared first solution was added into the second solution. While magnetically stirring at a rotation speed of 300 rpm, the first solution and the second solution were reacted at a temperature of 160°C for 6 h to obtain a reaction product. At the end of reaction, the reaction product was filtered and washed with deionized water and alcohol for three times, respectively, and then dried in an oven at 120°C for 12 h to eventually obtain the tricalcium phosphate material (p-TCP material) doped with Mg and Zn. The doping amount of Mg (mole ratio of Mg/(Ca+Mg+Zn)) was 10%, and the doping amount of Zn (mole ratio of Zn/(Ca+Mg+Zn)) was 5%. The morphology of the tricalcium phosphate material doped with Mg and Zn prepared in this embodiment was shown in Fig. 1, the XRD spectrum was shown in Fig. 3a, and the infrared spectrum was shown in Fig. 4a. Embodiment 2 In this embodiment, a tricalcium phosphate material (p-TCP material) doped with Mg and Zn was prepared by the following specific steps. 191.1 g of Ca(N03)2-4H20, 24.4 g of Mg(N03)2-6H20 and 14.2 g of Zn(N03)2-6H20 were dissolved in 1 L of deionized water and then stirred uniformly to obtain a first solution. 83.8 g of (NH4)2HP04 was dissolved in 1 L of deionized water, then stirred uniformly, and added dropwise with ammonia water having a mass fraction of 25wt% until pH was adjusted to 9.5, to obtain a second solution. The prepared first solution was quickly added into the second solution. While magnetically stirring at a rotation speed of 300 rpm, the first solution and the second solution were reacted at a temperature of 80°C for 24 h to obtain a reaction product.

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At the end of reaction, the reaction product was filtered and washed with deionized water and alcohol for three times, respectively, and then dried in an oven at 120°C for 12 h to eventually obtain the tricalcium phosphate material (p-TCP material) doped with Mg and Zn. The doping amount of Mg (mole ratio of Mg/(Ca+Mg+Zn)) was 10%, and the doping amount of Zn (mole ratio of Zn/(Ca+Mg+Zn)) was 5%. The tricalcium phosphate material doped with Mg and Zn prepared in this embodiment had a particle size of 30 nm to 50 nm. The morphology of the tricalcium phosphate material doped with Mg and Zn prepared in this embodiment was shown in Fig. 2, the XRD spectrum was shown in Fig. 3b, and the infrared spectrum was shown in Fig. 4b. Embodiment 3 In this embodiment, a tricalcium phosphate material (p-TCP material) doped with Mg and Zn was prepared by the following specific steps. 167.9 g of Ca(N03)2-4H20, 36.4 g of Mg(N03)2-6H20 and 28.2 g of Zn(N03)2-6H20 were dissolved in 1 L of deionized water and then stirred uniformly to obtain a first solution. 83.5 g of (NH4)2HP04 was dissolved in 1 L of deionized water, then stirred uniformly, and added dropwise with ammonia water having a mass fraction of 25wt% until pH was adjusted to 9.5, to obtain a second solution. The prepared first solution was quickly added into the second solution. While magnetically stirring at a rotation speed of 300 rpm, the first solution and the second solution were reacted at a temperature of 160°C for 6 h to obtain a reaction product. At the end of reaction, the reaction product was filtered and washed with deionized water and alcohol for three times, respectively, and then dried in an oven at 120°C for 12 h to eventually obtain the tricalcium phosphate material (p-TCP material) doped with Mg and Zn. The doping amount of Mg (mole ratio of Mg/(Ca+Mg+Zn)) was 15%, and the doping amount of Zn (mole ratio of Zn/(Ca+Mg+Zn)) was 10%. The XRD spectrum of the tricalcium phosphate material doped with Mg and Zn

16564100_1 (GHMatters) P114439.AU prepared in this embodiment was shown in Fig. 3c, and the infrared spectrum was shown in Fig. 4c. Embodiment 4 In this embodiment, a tricalcium phosphate material (p-TCP material) doped with Mg and Zn was prepared by the following specific steps. 167.9 g of Ca(N03)2-4H20, 36.4 g of Mg(N03)2-6H20 and 28.2 g of Zn(N03)2-6H20 were dissolved in 1 L of deionized water and then stirred uniformly to obtain a first solution. 83.5 g of (NH4)2HP04 was dissolved in 1 L of deionized water, then stirred uniformly, and added dropwise with ammonia water having a mass fraction of 25wt% until pH was adjusted to 9.5, to obtain a second solution. The prepared first solution was quickly added into the second solution. While magnetically stirring at a rotation speed of 300 rpm, the first solution and the second solution were reacted at a temperature of 80°C for 24 h to obtain a reaction product. At the end of reaction, the reaction product was filtered and washed with deionized water and alcohol for three times, respectively, and then dried in an oven at 120°C for 12 h to eventually obtain the tricalcium phosphate material (p-TCP material) doped with Mg and Zn. The doping amount of Mg (mole ratio of Mg/(Ca+Mg+Zn)) was 15%, and the doping amount of Zn (mole ratio of Zn/(Ca+Mg+Zn)) was 10%. The XRD spectrum of the tricalcium phosphate material doped with Mg and Zn prepared in this embodiment was shown in Fig. 3d, and the infrared spectrum was shown in Fig. 4d. The tricalcium phosphate material doped with Mg and Zn prepared in this embodiment was sprayed onto the titanium alloy Ti6AI4V by plasma spraying, that is, a P-TCP coating having a doping amount of Mg (mole ratio of Mg/(Ca+Mg+Zn)) of 15% and a doping amount of Zn (mole ratio of Zn/(Ca+Mg+Zn)) of 10% was prepared on the surface of the titanium alloy Ti6AI4V. Then, cells were cultured on the surface of the coating. It can be known from Fig. 5 that the cells spread well on the surface of the

16564100_1 (GHMatters) P114439.AU calcium phosphate material containing Mg and Zn, and tail feet of the cells stretched obviously. It indicated that the tricalcium phosphate material doped with Mg and Zn prepared by the present disclosure has good bioactivity. Embodiment 5 In this embodiment, photocurable 3D printing tricalcium phosphate ceramic slurry (with a solid content of 50%) was prepared by the following specific steps. 12 g of the tricalcium phosphate material powder doped with Mg and Zn prepared in Embodiment 1 (with a powder density of 3 g/cm 3 and a volume of 4cm 3

) was added into an organic resin solution. The organic resin solution was 4 mL of a mixed solution consisting of 3.68 mL of a photosensitive resin (1.45 mL of HDDA, 1.20 mL of G1122 and 1.03 mL of PEG400), 0.04 mL of a photoinitiator (TPO-L), 0.04 mL of a leveling agent (BYK 333), 0.04 mL of an antifoaming agent (BYK 052N) and 0.2 mL of a dispersant (BYK 111). The ratio of the volume of the tricalcium phosphate material powder doped with Mg and Zn to the volume of the organic resin solution was 1:1. The tricalcium phosphate material powder doped with Mg and Zn was fully grinded for 24 h to obtain nano-tricalcium phosphate ceramic slurry with a solid content of 50%. The nano-tricalcium phosphate blank obtained by 3D printing the ano-tricalcium phosphate ceramic slurry was shown in Fig. 6. It could be clearly found from Figs. 1 and 4 that the tricalcium phosphate material powder doped with Mg and Zn prepared by the method for preparing a tricalcium phosphate material powder doped with Mg and Zn provided in the embodiments of the present disclosure had a particle size of 30 nm to 150 nm. It could be found from Fig. 5 that the tricalcium phosphate material powder doped with Mg and Zn prepared in this embodiment of the present disclosure had good bioactivity. Moreover, it could be found from Fig. 6 that the nano-tricalcium phosphate ceramics obtained by 3D printing the photocurable 3D printing ceramic slurry that was prepared from the tricalcium phosphate material powder doped with Mg and Zn prepared in this embodiment of the present disclosure as ceramic powder had good compactness.

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The foregoing description merely shows preferred embodiments of the present disclosure and is not intended to limit the present disclosure in any form. Any simple modification, equivalent alteration and modification made to these embodiments

according to the technical essence of the present disclosure shall fall into the scope of the technical solutions of the present disclosure.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is

used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the

invention.

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Claims

1. A method for preparing a tricalcium phosphate material doped with Mg and Zn, wherein, in the tricalcium phosphate material doped with Mg and Zn, the number of moles of Mg is ni, the number of moles of Zn is n2, and the total number of moles of Ca, Mg and Zn is n3, where n1/n3 is 10% to 15%, and n2/n3 is 5% to 10%; wherein the tricalcium phosphate material doped with Mg and Zn has a particle size of 30 nm to 150 nm; and the method for preparing a tricalcium phosphate material doped with Mg and Zn comprises steps of: 1) reacting a first solution containing magnesium ions, zinc ions and calcium ions with a second solution containing phosphate ions at a set temperature for a set time to obtain a reaction product; wherein the set temperature is 80°C to 160°C; wherein, in the first solution, the number of moles of Mg is ni, the number of moles of Zn is n2, and the total number of moles of Ca, Mg and Zn is n3, where n1/n3 is 10% to 15%, and n2/n3 is 5% to 10%; and 2) washing and freeze-drying or baking the reaction product to obtain the tricalcium phosphate material doped with Mg and Zn.

2. The method for preparing a tricalcium phosphate material doped with Mg and Zn according to claim 1, wherein, in the step 1): the set time is 6 h to 24 h.

3. The method for preparing a tricalcium phosphate material doped with Mg and Zn according to claim 1, wherein, in the step 1): the first solution is a mixed solution of calcium salt, magnesium salt and zinc salt.

4. The method for preparing a tricalcium phosphate material doped with Mg and Zn according to claim 3, wherein the first solution is a mixed solution of calcium nitrate, magnesium nitrate and zinc nitrate.

5. The method for preparing a tricalcium phosphate material doped with Mg and

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Zn according to claim 4, wherein in the first solution, the calcium nitrate has a

concentration of 100 to 200 g/L, the magnesium nitrate has a concentration of 10 to 40 g/L, and the zinc nitrate has a concentration of 10 to 30 g/L.

6. The method for preparing a tricalcium phosphate material doped with Mg and

Zn according to any one of claims 1 to 5, wherein, in the step 1):

the second solution is an ammonium dihydrogen phosphate solution with a pH value adjusted by ammonia water.

7. The method for preparing a tricalcium phosphate material doped with Mg and

Zn according to claim 6, wherein ammonium dihydrogen phosphate has a concentration of 25 to 100 g/L; and/or

the second solution has a pH value of 8.5 to 9.5.

8. The method for preparing a tricalcium phosphate material doped with Mg and Zn according to claim 6, wherein the ammonia water has a mass fraction of 20wt% to

30wt%.

9. The method for preparing a tricalcium phosphate material doped with Mg and Zn according to claim 8, wherein the ammonia water has a mass fraction of 25wt%.

10. The method for preparing a tricalcium phosphate material doped with Mg and Zn according to any one of claims 1 to 5, wherein, in the step 1):

the volume ratio of the first solution to the second solution is (1:1.2) to (1.2:1).

11. The method for preparing a tricalcium phosphate material doped with Mg and

Zn according to claim 10, wherein the volume ratio of the first solution to the second

solution is (1:1.1) to (1.1:1).

12. The method for preparing a tricalcium phosphate material doped with Mg and Zn according to claim 11, wherein the volume ratio of the first solution to the second solution is 1:1.

13. The method for preparing a tricalcium phosphate material doped with Mg and Zn according to any one of claims 1 to 5, wherein in the second solution, the number

of moles of phosphorus is n4, where n3/n4 is 1.45 to 1.65.

18805842_1 (GHMatters) P114439.AU

14. The method for preparing a tricalcium phosphate material doped with Mg and Zn according to claim13, wherein n3/n4 is 1.5.

15. The method for preparing a tricalcium phosphate material doped with Mg and Zn according to any one of claims 1 to 5, wherein the step 1) is specifically: adding the first solution into the second solution, and reacting, while stirring, the first solution and the second solution at the set temperature for the set time.

16. 3D printing ceramic slurry, wherein ceramic powder in the 3D printing ceramic slurry is tricalcium phosphate material doped with Mg and Zn; wherein the tricalcium phosphate material doped with Mg and Zn is made by the method according to any one of claims 1 to 15.

17.The 3D printing ceramic slurry according to claim 16, wherein the 3D printing ceramic slurry comprises ceramic powder and an organic resin solution, the ceramic powder having a volume fraction of 30% to 60% and the organic resin having a volume fraction of 40% to 70%.

18. The 3D printing ceramic slurry according to claim 17, wherein the organic resin solution comprises: a photocurable resin having a volume fraction of 92% to 98.7%, a photoinitiator having a volume fraction of 0.1% to 1%, a leveling agent having a volume fraction of 0.1% to 1%, an antifoaming agent having a volume fraction of 0.1%to 1%, and a dispersant having a volume fraction of 1%to5%.

19. A method for preparing 3D printing ceramic slurry according to any one of claims 16-18, comprising steps of: adding ceramic powder into an organic resin solution, and grinding to obtain the 3D printing ceramic slurry; wherein the grinding lasts for 5 h to 30 h.

20. The method for preparing 3D printing ceramic slurry according to claim 19, wherein the grinding lasts for 10 h to 25 h.

18805842_1 (GHMatters) P114439.AU