Assembly Synthesis Of Hydroxyapatite With Hierarchical Structure And Study On Formation Mechanism

As one kind of materials of biominerals,hydroxyapatite possess excellent biocompatibility and biological activity and.In addition,it is one of the most widely used biomedical materials.According to the perspective of biomimetic mineralization,a series of synthesis methods of hydroxyapatite has been derived,including template-assisted methods.The previous research often focused on the regulation function of inorganic mineral and ignored the inorganic mineral on organic matter.Face recognition theory suggested that inorganic also has a certain influence on organic.Herein,we report a new combination of surfactant(mnno-alkyl phosphate,MAP and polyvinylpyrrolidone,PVP)and citrate to prepare radial bundles hydroxyapatite by hydrothermal treatment.Using X-ray powder diffraction(XRD),Fourier Transform infrared spectroscopy(FTIR),Scanning Electron Microscope(SEM),Transmission electron microscopy(TEM),Thermal analysis(DSC-TG)to investigate the morphologies and structures of hydroxyapatite,exploring the reaction temperature,reaction time,additive amount of MAP,pH of precursors in tailing of the morphology of product.The possible mechanism of the morphogenesis of the structure and interaction between organic and inorganic phase was investigated.The results showed that spherical crystal assembly of hydroxyapatite and radial bundles hydroxyapatite were achieved with assistance of PVP and MAP,respectively,the former size of spherical crystal was about 1 μm,and the latter size of radial bundles hydroxyapatite was about 3 μm.We analyzed the template agent molecular regulation function of HAP crystals and sodium citrate molecules in HAP crystal adsorption,and a organic-inorganic interaction theory model was put forward.The structure of radial bundles hydroxyapatite can be controlled through change the reaction temperature,reaction time,additive amount of MAP,pH of precursors.To investigate the Zeta potential value of product,conductivity and pH value changes of precursors before and after the reaction,we further studied the mechanism of organic-inorganic interaction during the process of reaction and provided some theoretical guidance for the template-assisted methods of inorganic minerals.Investigation in synthesis of hydroxyapatite and the interaction of organic and inorganic can improve the molecular recognition theory of organic-inorganic interface and deepen our understanding of the biomineralization mechanism,which can provide theoretical basis for biomimetic design and synthesis of a particular materials(such as artificial bone and teeth).Moreover,it will improve our scientific understanding of life evolution which might be useful for the development of biomimetic materials.