Abstract
A porous hydroxyapatite (HA) - incorporated TiO2 coating layer was deposited on the titanium substrate using a combination of micro-arc oxidation and electrophoretic deposition. The size of the synthesized HA nano-particles was approximately 10-20nm in width and 30-40nm in length. The microstructure, as well as elemental and phase composition of the coating layers were examined by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). XRD showed that the coating layers were composed mainly of HA and anatase phases. The composition and surface morphologies were strongly dependent on the applied voltages. The amount of HA deposited into the coating increased with increasing applied voltage. The corrosion behavior of the coating layers in the simulated body fluids (SBF) was evaluated using a potentiodynamic polarization test. The corrosion resistance of the coated sample was higher than that of the untreated titanium sample. Moreover, the corrosion resistance of the coated samples also showed a positive correlation with the applied voltage. In addition, the in vitro cellular responses to the coated samples were assessed to investigate the proliferation, differentiation and morphology of the osteoblast cell line. (C) 2011 Elsevier B.V. All rights reserved.