贝壳表面沉积片状磷灰石及其体外生物活性

采用溶液浸泡法将贝壳在37 ℃转化成磷灰石,借助XRD、FTIR、SEM、TEM等分析手段研究磷灰石的形貌、结构和体外生物活性.贝壳在磷酸缓冲溶液中浸泡24 h后,通过溶解-再结晶反应在其表面沉积上一层具有片状形貌的缺钙型磷灰石,其Ca/P比为(1.35±0.05).低温下制备的磷灰石结晶度较低,而且晶格内含有碳酸根和磷酸氢根离子.SBF实验表明,以贝壳为原料制备的磷灰石具有优良的体外生物活性,试样在SBF溶液中浸泡12 h后表面就沉积上一层类骨型磷灰石.预计溶液浸泡法制备的磷灰石可应用于骨支架材料或者填充材料.

Deposition of Plate-Like Apatite on Nacre Surfaces and Its in Vitro Bioactivity

Apatite was converted from nacre by treatment with a phosphate buffer solution (PBS) at 37 ℃. The morphology, structure, and thermal stability of the apatite were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). After soaking in PBS for 24 h, the carbonate apatite plates with a Ca/P molar ratio of 1.35±0.05 are deposited on the nacre surfaces via a dissolution-recrystallization reaction. The crystalline of apatite obtained at low temperatures is low, and the PO_4~(3-) and OH- ions in the lattice are replaced partly by HPO_4~(2-) and CO_3~(2-) ions. Simulated body fluid (SBF) immersion tests reveal that the apatite converted from nacre exhibits a superior in vitro bone-forming bioactivity. The apatite may be promising for bone scaffold materials and bone cavity filling materials.