Abstract: The composite of nanocrystalline apatite coated rutile TiO₂ was prepared by soaking TiO₂ nanosized powders into the simulated body fluid (SBF) at 37℃ for the different duration times. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), highresolution transmission electron microscope (HRTEM), energy dispersive X-ray (EDX), fourier transform infrared (FTIR) spectroscope, inductively coupled plasma atomic emission spectrometer (ICP-AES) and N2 adsorption measurements. XRD result shows that the content of the apatite coated on the rutile TiO2 increases with prolonging the soaking time in the SBF. It is demonstrated that composite powders have included some apatite through the absorption peaks of the O-H and PO₄^3-of the apatite in the FTIR spectrum. ICP-AES result shows that Ca and P concentrations decrease with prolonging the soaking time in SBF. It is evident from the TEM and EDX that there is some apatite coated on the surfaces of the rutile TiO₂. HRTEM result indicates that the interplanar spacing of (211) of the apatite is 0.27nm and the diameter of apatite nanoparticles is about 40nm.

Key words: rutile, apatite, SBF, titanium dioxide