Crystallization of Hydroxyapatite on Oxadiazole-Based Homopolymers

Abstract

Oxadiazole homopolymer was found to be a substrate favoring the deposition of hydroxyapatite (HAP) crystals from stable supersaturated solutions at pH 7.40, 37 °C, and 0.15 M NaCl. The second-order dependence of the precipitation of HAP on oxadiazole polymer on the solution supersaturation suggested a surface diffusion controlled mechanism. The surface energy of the HAP nuclei growing on oxadiazole homopolymer was calculated to be 158 mJ m-2 from the dependence of crystal growth rate on the solution supersaturation. The overgrowth of HAP on the polymer was done selectively possibly through active site formation on −N−N− groups on the macromolecules as confirmed by computational chemistry calculations at 310 K.