Abstracto

Effect of aging time on calcium phosphates powders obtained by sol-gel method

M.L.dos Santos, C.S.Riccardi, A.L.Noronha, G.M.de Olyveira, E.A.Filho, A.C.Guastaldi

Calcium phosphates (CaP) based bioceramics play role in several biomedical applications. In this study,hydroxyapatite (Ca10(PO4)6(OH)2) was synthesized by sol-gelmethod. Calciumnitrate (Ca(NO3)2.4H2O) and phosphoric acid (H3PO4) were used as calcium and phosphate precursors in methyl alcohol solvent. The influence of the aging time (12 h, 24 h, 10 days, 20 days and 30 days) of the sol on the structure of the CaP powders was investigated. The results of stability showed that it remained stable not altering the final powder during one month. After remove the solvent by heating at 100°C a white powder was obtained. The effect of calcination temperatures on composition of the HA phase were characterized by FTIR, XRD and SEM. These techniques confirmed the presence ofthe typical hydroxyapatite phase and CaO. The results ofhydroxyapatite synthesized by sol-gel method showed a required stability to be applied on coating ofdentistry and orthopedic implant using the sol prepared at the period of one month.