Effect of amino acids on the crystal growth of hydroxyapatite

Abstract: The purpose of this study was to investigate the effect of amino acid on the morphology and crystallinity of nano-sized hydroxyapatite (HAP) crystals via a chemical precipitation method in the presence of l-lysine and l-tyrosine at different concentrations. The products were characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. The results showed the effect of l-lysine and l-tyrosine on the crystal growth of HAP was at opposite poles, i.e., the crystal growth was inhibited by l-lysine but promoted by l-tyrosine depending on the amino acid content. The mechanism of HAP crystal growth was also proposed. [Copyright &y& Elsevier]