A Novel Method of Preparing a Nanometer-Scale Rod Array of Hydroxyapatite Crystals

Abstract

This study proposed a new strategy for preparing self-assembling one-dimensional HAp nanorods into organized superstructures. We employed glass of a few specific compositions in the system Na2O-CaO-SiO2 because it may yield Si-OH groups on the surface when soaked in an aqueous system, and their formation is one of the key factors to induce apatite nucleation. A nanometerscale rod array of HAp having preferred orientation to the c-axis was successfully prepared simply by soaking the soda-lime silica glass substrates in Na2HPO4 aqueous solution at 80 °C. Those HAp rods grew up perpendicularly to the glass surface, and the crystallites covered glass surface uniformly, resulting in “dental enamel-like� rod array structure. The present procedure is significant as it allows to design biomimetic materials and therapeutic agents with applicable both the biomedical and material science fields because the nano-textured HAp crystals exhibit a hierarchical architecture and may provide specific cell attachment and proliferation with controlled planes of growth and nano- and micrometer-scale topography.