Apatite formation on carbon nanotubes

Apatite coating on carbon-nanotubes (CNTs) was done with a biomimetic coating method. The multi-walled CNTs (MWNTs) of curled shape with about 30 nm in diameter were immersed for 2 weeks in the simulated body fluid. Observation by scanning electron microscopy (SEM) showed the formation of apatite on the MWNTs surface. The clusters of spherules consisting of needle-shaped apatite crystallites were massively grown on the aggregated MWNTs. The crystallites of 100 nm in width and 200-500 nm in length were grown perpendicularly to the longitudinal direction and radially originating from a common center of a single MWNT. Thus, the architecture of crystalline apatite at nano-scale levels could be produced by simple method and the MWNT may be acting as core for initial crystallization of apatite. (c) 2005 Elsevier B.V. All rights reserved.