Fabrication of highly ordered macroporous apatite coating onto titanium by electrophoretic deposition method

A fabrication of highly ordered macroporous bioactive ceramic coating was conducted and its biocompatibility in vitro was evaluated. HAp coating material having highly ordered macropores was prepared onto a titanium substrate by an electrophoretic deposition (EPD) process combined with a heat treatment. First, a mixture of monodisperse polystyrene (PS) spheres (3 μm in diameter) and HAp fine particles (200–300 nm in size) suspended in ethanol solution was deposited on the substrate by the EPD in order to prepare an organic–inorganic composite film. Then, the composite film was heated at 900 °C to remove the organic PS spheres and sinter the inorganic HAp particles. An observation with scanning electron microscopy revealed the presence of HAp film having highly ordered macropores. This is due to a formation of composite particles consisting of PS and HAp in the EPD suspension. Titanium plate coated with porous HAp had a good biocompatibility in vitro, which was confirmed by in vitro test using a simulated body fluid (SBF).