【摘要】 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PO₄^3-的吸收峰呈减弱趋势,证明SiO44?部分取代了PO₄^3-。FTIR光谱和荧光光谱分析表明:Si-HA与BSA作用后的PO₄^3-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+,PO₄^3-,SiO₄^4-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。更多还原

【Abstract】 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 34? in the Si-HA decreases, and the fluorescence intensity in the BSA is quenched. With the substitution of 4 SiO 4? for PO 34? , 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 Ca2+ in Si-HA binding negative —COOH– in the BSA and SiO 44? , and the PO 34? 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.更多还原