含硅羟基磷灰石生物陶瓷的湿法合成及结构特征(英文)

WET SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF BIO-CERAMICS WITH SILICON-SUBSTITUTED HYDROXYAPATITE

将硅(Si)掺入羟基磷灰石(hydroxyapatite,HA)的晶格中能有效提高HA的生物活性。用湿法合成了含硅的羟基磷灰石微粉(Si-HA)。用X射线荧光光谱、X射线衍射、红外光谱(Fourier transform infrared spectroscopy,FTIR)、扫描电镜和荧光光谱等对Si-HA的晶相、结构、化学组成、形貌及其与牛血清白蛋白(Bovine serum albumin,BSA)的相互作用进行了表征和分析。结果表明:Si元素溶入HA晶格中,使HA晶胞参数和结构发生变化。随着Si含量的增加,HA中—OH和PO_4^(3-)的吸收峰呈减弱趋势,证明SiO44?部分取代了PO_4^(3-)。FTIR光谱和荧光光谱分析表明:Si-HA与BSA作用后的PO_4^(3-)吸收峰和蛋白质内源的荧光光谱明显减弱,在Si-HA荧光光谱中出现了蛋白质的酰胺Ⅰ带和酰胺Ⅱ带吸收峰,吸收峰随Si质量分数的增加而增强。与纯HA与BSA的作用相比,Si-HA与BSA的作用更强,说明Si-HA中的Ca2+,PO_4^(3-),SiO_4^(4-)与BSA之间发生了相互溶解、吸附和键合等作用,证明Si-HA与生命物质蛋白质之间具有高的反应活性。本文详尽阐述了Si-HA的生物活性及其与BSA相互作用的机理。

The incorporation of silicon into the hydroxyapatite （HA） lattice can improve the bioactivity of HA. Silicon-substituted HAs （Si-HA） have been prepared by incorporating a small amount of silicon into a HA lattice via an aqueous precipitation reaction. The crystalline phase, microstructure, chemical composition and morphology of the Si-HA and the interaction between Si-HA and BSA were characterized by X-ray fluorescence spectroscopy, X-ray diffraction and fluorescence. The results show that the proposed substitution of the silicon （or silicate） ions for the phosphorus （or phosphate） ion in the HA. Analysis of the Si-HA by Fourier trans- form infrared spectroscopy （FTIR） indicates that the silicon substitution affect the FTIR of the HA in the P-O and O-H vibrational bands, and the intensity of the absorption peak of the O-H and P-O in the Si-HA is lower than that in the HA. The intensity of the absorption peak of PO^3-4 in the Si-HA decreases, and the fluorescence intensity in the BSA is quenched. With the substitution of SiO^4-4 for pO^3-4 , and the absorption peak of the amide group （-CONH2） in BSA is observed in the silicon-substituted HA substrate by FTIR. It is suggested that the Si-HA-BSA complexes have been formed by positive Ca^2＋ in Si-HA binding negative -COOH- in the BSA and SiO^4-4, and the pO^3-4 in the Si-HA binding to -NH2 in the BSA. On the basis of these results, the better bioactivity mechanism of Si-HA than that of HA is discussed.