掺锶羟基磷灰石的制备与性能研究

Preparation and Property of Strontium-substituted Hydroxyapatite

掺锶羟基磷灰石的骨缺损修复效果优于羟基磷灰石.以四水硝酸钙[Ca(NO_3)_2·4H_2O]、磷酸氢二铵[(NH_4)_2HPO_4]、硝酸锶[Sr(NO_3)_2]为原料,180℃下水热处理8h制得Sr-HA.通过XRD、FTIR、TEM、EDX和TG/DTA对Sr-HA的晶相、化学组成、形貌和热稳定性进行分析,并通过细胞培养,MTT比色法对材料的细胞毒性进行评价.结果表明:Sr取代部分Ca进入HA的晶格中.随着Sr含量的增加,Sr-HA晶粒尺寸呈减小趋势,热稳定性下降.掺锶对羟基磷灰石细胞毒性影响较小,锶磷灰石具有良好的生物相容性.

The biological HA in the body differs from that of pure HA in stoichiometry,composition,physical properties and mechanical properties,because this HA is particularly prone to ion substitution.As a cation that can substitute for calcium in the structure of hydroxyapatite,strontium provokes an increasing interest because of its beneficial effect on bone formation,and prevention of bone resorption.Here,strontium-substituted HA powders were prepared by the hydrothermal method at 180℃for 8 h using Ca（NO3）2·4H2O,（NH4）2HPO4 and Sr（NO3）2 as reagents.X-ray diffraction,Fourier transform infrared spectroscope,transmission electron microscope,energy dispersive X-ray,and thermogravimetric-differential thermal analysis were employed to investigate the crystalline phase,chemical composition,morphology,and thermal stability of the Sr-HA.And the cytotoxicity of Sr-HA was analyzed through MTT assay.The results show that Sr is incorporated into the HA crystal structure and the crystal grain size of the Sr-HA decreases as the Sr content（under 50wt%） is increased.Moreover,the HA thermal stability decreases.However,there＇s no apparent difference between the pure hydroxyapatite and all of the Sr-HA groups in cytotoxicity,which may have good biocompatibility.