Preparation and Property of Strontium―substitutedHydroxyapatite

The biological HA in the body differs from that of pure HA in stoichiometry,composition, physical properties and mechanical properties, because this HA isparticularly prone to ion substitution. As a cation that can substitute forcalcium in the structure of hydroxyapatite, strontium provokes an increasinginterest because of its beneficial effect on bone formation, and prevention ofbone resorption. Here, strontium―substituted HA powders were prepared by thehydrothermal method at 180 for 8 h using Ca(NO3)2·4H2O, (NH4)2HPO4and Sr(NO3)2 as reagents. X―ray diffraction, Fouriertransform infrared spectroscope, transmission electron microscope, energy dispersiveX―ray, and thermogravimetric―differential thermal analysis were employed toinvestigate the crystalline phase, chemical composition, morphology, and thermalstability of the Sr―HA. And the cytotoxicity of Sr―HA was analyzed through MTT assay. The results showthat Sr is incorporated into the HA crystal structure and the crystal grainsize of the Sr―HA decreases as the Sr content (under 50wt%) is increased.Moreover, the HA thermal stability decreases. However, there’s no apparentdifference between the pure hydroxyapatite and all of the Sr―HA groups in cytotoxicity,which may have good biocompatibility.