Abstract
Microstructure designed granular hydroxyapatite (Ca10(PO)4(OH)2; HA) was prepared by hydrothermal method. The size of granules of less than 100 μm, the shape of particles in the granules, and the micro-pore of about 0.1 μm in size of the granules were controlled. The granular HA prepared at 200°C for 20 h was composed of rod-shaped crystals of about 50 μm in length with the mean aspect ratio of 50. Rod-shaped HA crystals were locked together to make micro-pores of about 0. 1 μm in size. It was non-stoichiometric HA with calcium deficient composition. This granular HA must have the advantage of adsorptive activity, because the HA has many specific crystal surface and micro-pores.
