Synthesis of nanosized carbonated hydroxyapatite using microwave irradiation

In order to accelerate the synthesis of carbonated hydroxyapatite (CHA), nano-sized carbonated hydroxyapatite powders were rapidly prepared under microwave irradiation using Ca(NO3)2-4H(2)O, (NH4)(2)HPO4 and NH4HCO3 as the starting materials. The morphologies and particle sizes of the resulting CHA powders were investigated by TEM and XDR analysis. The phase, type and thermal stability of CHA also were investigated by XDR, FT-IR. The results showed that the AB-type CHA powders synthesized were rod-like nanocrystals with dimension in the 15 similar to 30 nm and with length 40 nm. The calcination temperature had a significant influence on the phase composition and carbonate content of CHA. It was found that CHA could stably exist at calcination temperature of 700 degrees C, but it was partly, decomposed into TCP and removed CO2 above 900 V. As a result, biphasic ceramic powders consisting of HA and beta-TCP were obtained. It is concluded that microwave synthesis is a rapid and effective method for synthesis of nanosized carbonated hydroxyapatite with high thermal stability.