EN
Different precursor chemicals (3Ca(OH)_2, Ca(NO_3)_2 and CaO as Ca^{2+} sources, H_3PO_4 and (NH_4)_2HPO_4 as PO_4^{3-} sources were used to synthesis of nanosized hydroxyapatite powder with ultrasonic precipitation method. The effect of different chemical precursors was investigated. Sample characterization was achieved by powder X-ray diffraction, the Fourier transformed infrared transmission spectroscopy, zeta sizer, scanning electron microscopy, density and surface area measurements.