Characterization of properties in microwave irradiated-hydroxyapatite

Hydroxyapatite (HA) is a calcium phosphate with a chemical bond of Ca₁₀(PO₄)₆(OH)₂, which is similar to the inorganic substance contained in human bones. Thus makes HA convenient for further development as a biomaterial. The aim of this work is to understand the effect of variation in microwave power and time in synthesizing HA. HA was synthesized by a mixture of calcium hydroxide and di-ammonium hydrogen phosphate, maintaining the molar ratio between calcium and phosphate of 1.67. The sample was irradiated by microwave irradiation at different powers and time duration. The properties of all samples were investigated by x-ray diffraction (XRD), Fourier-transform infrared (FTIR), scanning electron microscopy and energy dispersive x-ray spectroscopy (SEM-EDX). The mass of HA samples showed a quite significant change while the crystallite size of the samples reached 34.99 nm. The FTIR results showed some carbonate peaks. It is proved that the change in irradiation power and time affects the properties of the synthesized HA. The synthesized HA powders showed a similar structure to hydroxyapatite in hexagonal P63/m space group a=b=9.418 and c=6.887.