Two step synthesis of CaP/TiO2 nanorod composite coatings with improved protein adsorption

• Composite coatings of TiO2 nanorod array and calcium phosphate
• Controllable relative content of calcium phosphate in the coating
• Improved protein adsorption ability of the coatings

Titanium dioxide (TiO2) nanorods and calcium phosphate (CaP) composite coatings were prepared and characterized. TiO2 nanorod films were grown on titanium substrates via a hydrothermal method. Then, calcium phosphate was deposited into TiO2 nanorod films electrochemically in an aqueous electrolyte containing calcium and phosphorus species. As a result, CaP/TiO2 nanorod coatings were obtained. The amount of calcium phosphate deposited could be controlled through varying temperature, voltage and duration. It was found that both the presence of calcium phosphate and UV treatment could affect the surface wettability of the composite coatings. A bovine serum albumin adsorption test showed that the protein adsorption ability of the composite coatings was also improved with the presence of calcium phosphate and UV treatment. Moreover, the presence of calcium phosphate could promote the deposition of bone-like minerals. It is suggested that such coatings may exhibit promising initial cellular responses and thus be a good alternate for bioactive coatings.