Synthesis and Characterization of Silicon-Doped Hydroxyapatite

Abstract

Silicon was doped to hydroxyapatite by hydrothermal techniques for higher biocompatibility. Products contained tetra-ethyl-orthosilicate (TEOS) as a silicon source in the range of 0 to 15 mass%. In order to evaluate bioactivity of silicon-doped hydroxyapatite, the samples were soaked in simulated body fluid (SBF). Silicon doped samples showed faster apatite forming ability than the undoped samples. The samples were examined by transmission electron microscopy (TEM), X-ray diffraction patterns (XRD), Fourier transform infrared spectroscopy (FTIR) and X-ray absorption fine structure (XAFS). There results indicated that SiO₄⁴⁻ ion substituted PO₄³⁻ ion site in apatite structures. And it was found that appropriate TEOS doping ratio was 10 mass% for superior biocompatibility due to amorphous SiO₂ segregation in the 15 mass% TEOS doped samples.