Hydroxyapatite nanoparticles: A review of preparation methodologies.

Hydroxyapatite (HA) has been widely used as a biocompatible ceramic in many areas of medicine, but mainly for contact with bone tissue, due to its resemblance to mineral bone. In mammals, the skeleton presents a carbonated and partially substituted apatite, based on nanocrystal aggregates, and associated with collagen, building up 3-D structures present in various bone tissue conformations like trabecular or cancellous bone. There has been growing interest in developing bioactive synthetic ceramics that could closely mimic natural apatite characteristics. This review presents some of the most well known forms of obtaining, by precipitation methods, nanophased HA. Some traditional and more recent developments vis-à-vis the pos-sible HA nanoparticles applications are discussed.