Hydrothermal Synthesis of Hydroxyapatite from Octacalcium Phosphate

Abstract

Plate-shaped particles of octacalcium phosphate (OCP) were hydrothermally treated with distilled water at 120-240 ºC for 3-24 h. Only the diffraction lines assigned to hydroxyapatite (HA) were detected by X-ray diffraction even after the treatment at the lowest temperature of 120 ºC for the shortest time of 3 h. In addition, plate-shape morphology originating from OCP was observed under this mildest treatment condition. However, plate-shaped particles split into small strip-shaped particles when the treatment temperature and time increased. Hydrothermal treatments of OCP in mild conditions are therefore useful to synthesize plate-shaped HA particles.