Preparation of amino-acid-regulated hydroxyapatite particles by hydrothermal method

The hydroxyapatite nanorods (about 80 nm in length and 15 nm in width) with uniform size were achieved by hydrothermal method at 100 °C and pH 10 in the presence of alanine and glutamic acid. A special instillment order was used and the prepared powders were characterized for phase composition by X-ray diffraction and Fourier Transform infrared spectroscopy. The size and morphology of HAP nanoparticles were studied by Transmission electron microscopy. The characterization showed that the amino acid could induce the synthesis of hydroxyapatite nanoparticle and control HAP crystal growth when HAP crystal was formed. An instable monetite phase (CaPO₃OH) was found in the progress of ACP transforming to HAP.