2007 Volume 48 Issue 11 Pages 2855-2860
Hydroxyapatite (HAp) is the main mineral component of bone and is used as a raw material for artificial bones and teeth, and as an adsorbent in liquid chromatography, among its other uses. As a result of its anisotropic crystal structure, HAp shows adsorption behavior that depends on the crystal plane. However, the differences between the a-plane and the c-plane of the HAp crystal in terms of their bioactivity, cell-propagation behavior, etc., have not yet been fully clarified. In this study, we fabricated highly crystallographically aligned samples of HAp by using a 10-T magnetic field, and we studied the effects of the specific crystal plane of HAp on its bioactivity by immersing the samples in a simulated body fluid.
HAp is precipitated on both a-plane- and c-plane-aligned HAp sample surfaces. The rate of precipitation on a HAp sample immersed in the simulated body fluid depended on the crystal plane, especially during the first 24 h of immersion. Because the rate of precipitation on the c-plane is faster than on the a-plane, HAp is precipitated preferentially on the c-plane during the early stages of precipitation.