Fabrication of high-dispersibility nanocrystals of calcined hydroxyapatite

Excerpt

Hydroxyapatite (HAp) is a major inorganic component of bone and teeth. Artificially synthesized HAp has been extensively used in a variety of applications, such as biomaterials, ion exchangers, adsorbents, and catalysts, by exploiting its biocompatibility and adsorbability of many compounds. When low-crystallinity HAp nanoparticles are calcined to increase thermal and chemical stability, the particles typically sinter into a large agglomerate consisting of polycrystal [1‐5]. Thus, calcined HAp crystals dispersed in liquid medium on a nanoscale have been difficult to obtain. This paper describes the fabrication of HAp nanocrystals by calcination with an anti-sintering agent interspersed between the particles and the subsequent removal of the agent. The HAp nanocrystals obtained here should be suitable for the above applications owing to their high dispersibility in liquid media, high specific surface area, and high thermal and chemical stability. …