Characteristics of surface and electrochemical properties of composites with fumed metal oxides and hydroxyapatite

Hydroxyapatite composite is a very important biomaterial, which can be applied in various life areas. Hydroxyapatite and its composites with fumed oxides ST20, AST1, Al 2 O 3 , A90, and A300 were prepared and studied using X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy adsorption, potentiometric titration, quasi-elastic light scattering and zeta potential measurements. The values of pH pzc (the point of zero charge) and pH IEP (the isoelectric point) characteristic of the electrical double layer depend on the type of the fumed oxide matrix. Comparative studies of hydroxyapatite, fumed oxides and composites by adsorption and desorption of nitrogen, scanning electron microscopy and FTIR showed that in most cases composites have properties intermediate between hydroxyapatite and the oxides taken for the synthesis.