A novel method to synthesize nanocrystalline hydroxyapatite: Characterization with x-ray diffraction and infrared spectroscopy

Abstract

Hydroxyapatite Ca 10 (PO4) 6 (OH) 2 (HA) is an important biomaterial and is the principal inorganic constituent of bones and teeth. It is also used as implant in the human body. By this investigation, hydroxyapatite nanostructured (18-56 nm) powders were prepared using novel wet precipitation method with calcium hydroxide and orthophosphoric acid solution as calcium and phosphorus precursors respectively. The Ca/P molar ratios of initial reagents are equal to 2.5. The HA filtered was dried at 90°C and calcined to different temperatures (300-1000°C). X-ray diffraction and Fourier transform infra-red spectroscopy used to characterize the calcined powder. The calcination reveals HA nano-powders. The particle size and crystallinity increase with the temperature. We note the formation of CaO at 1000°C. The refinement of cells parameters was performed by Fullprof-suite program. Thermal analysis (TG-DTA) was carried out to investigate the thermal stability of the powder.