The Sythesis And Biological Performances Of Trace-element Doped Hydroxyapatite

Hydroxyapatite Hydroxyapatite[Ca₁₀（PO₄）₆（OH）₂,HAp]is a bioactive material with good biocompatibility and biological activity.It is currently the most widely used hard tissue repair material in clinical practice.However,there is a very large difference in the structure and composition of artificially synthesized pure hydroxyapatite materials and hydroxyapatite in human skeletal tissues.The inorganic minerals in human hard tissues have very fine multi-level ordering.Structure,and includes many trace elements,such as F^-,CO₃^2-,Sr²⁺,Zn²⁺,Al³⁺,SiO₄⁴⁺,Na⁺,and rare earth ions.Therefore,from the standpoint of compositional bionics,the method of modifying ordered structures and doping ions to make synthetic hydroxyapatite have the same biological properties as human hard tissue is a significant research topic.The research content and results of this paper are as follows:1.Zn elements can participate in biomineralization of human bones in humans.Therefore,a series of zinc-doped hydroxyapatite（Zn/HAp）biomaterials were first prepared.The Zn-doped HAp nanoparticles still maintain the phase composition and main chemical groups of pure HAp.Trace Zn/HAp has a very strong protein adsorption capacity.Moreover,the micro-doped Zn/HAp biomaterial has no cytotoxicity to osteoblasts and has excellent cell compatibility.Micro-doping Zn/HAp biomaterials can promote the adhesion and proliferation of MC3T3-E1 cells,and significantly promote the secretion of ALP in MC3T3-E1 cells,thereby increasing osteoblast differentiation ability.These research results have very important guiding significance for the subsequent design of multiple doped hydroxyapatite hard tissue repair materials.2.Based on the content of trace elements in human hard tissues,ternary HAp biomaterials[Ca_9.989Zn_0.005Sr_0.006（PO₄）₆（OH）_1.94F_0.06]were synthesized with Zn,Sr,F（in which elements The concentrations were Zn:325 ppm Sr:523 ppm F:1000 ppm）.XRD analysis showed that the synthesized material was mainly HAp phase.HAp and ZnSrF/HAp materials have a similar orderly microstructure.The in vitro cytotoxicity test results demonstrated that ZnSrF/HAp has excellent biocompatibility and no cytotoxicity at low concentrations.This material can also significantly promote osteoblast MC3T3-E1 adhesion and proliferation on the surface,and promote cell secretion of ALP,which significantly increased the osteogenic differentiation capacity of cells,rapid generation of new bone tissue.Although the doping concentrations of Zn,Sr,and F are very small,the biological activity of the material is still significantly improved under the interaction of the three beneficial elements,indicating that trace functional elements are important in the application of hard tissue implant materials.significance.In this study,biomimetic synthesis of hydroxyapatite was carried out,and a large amount of valuable experimental data and information was obtained,which provided new perspectives and ideas for biomimetic synthesis and application of hydroxyapatite biomaterials.