Study On The Synthesis Of Hydroxyapatite In The Presence Of β-cyclodextrin And Its Drivative

Hydroxyapatite (Ca10(PO4)6(OH)2, HA or HAP) is a biomaterial of implants with favorable properties due to its excellent biocompatibility and bioactivity. It is one of research focuses in biomedical materials. Synthesized HA with special morphologies and size develop its application in many areas. But usingβ-Cyclodextrin and its derivatives as template to synthesize HA was barely reported. This paper studied the preparation of rod, rainy nano-HA and hollow sphere micro-HA usingβ-CD, its derivative CM-β-CD, the mixed system ofβ-CD and surfactant as template.This studies take Ca(NO3)2·4H2O and Na3PO4·12H2O as reagents, a certain concentration ofβ-cyclodextrin (β-CD) or carboxymethyl-β-cyclodextrin (CM-P-CD) as template. By controlling the concentration of P-CD or CM-β-CD,105～151.7 nm rod HA and 50～80nm rainy HA with specific surface area 150 m2·g-1 were obtained by hydrothermal method. This studies take Ca(NO3)2·4H2O and (NH4)PO4·3H2O as reagents, the mixed system ofβ-CD and surfactant as template. By controlling the concentration or ratio ofβ-CD and cetyltrimethylammonium bromide (CTAB), hollow sphere HA sized 1～2μm were obtained by biomineralization.The obtained samples was characterized by X-ray powder diffraction (XRD) analysis, Fourier-transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), Thermogravimetric analyzers (TG), ultraviolet spectrophotometer (UV) and Electrical conductivity (EC). It is indicated thatβ-CD self-assemble form long chains in axial direction. And then they induce HA growth along the chain, resulting in longer HA rods. CM-β-CD interacts with Ca2+ in HA crystalline, and then the growth of HA is hindered. In the mix system ofβ-CD and CTAB, the spacial structure ofβ-CD including CTAB is used as template during the formation of hollow sphere micro-HA.