Published online by Cambridge University Press: 31 January 2011
Titania coatings with various morphologies were formed on titanium surfaces by hydrothermal treatment using a dilute alkaline solution and evaluated in their hydroxyapatite (HA)-forming abilities in simulated body fluid (1.5SBF) under ultraviolet (UV) irradiation. The HA formation on the titania coating in 1.5SBF was enhanced by UV irradiation. The amount of phosphate groups adsorbed on the titania, after soaking in 1.5SBF for 24 h under UV irradiation, was estimated to be larger than that of calcium ions, whereas that of calcium ions on the titania, after soaking without UV irradiation, was larger than that of phosphate groups. It was suggested that the titania generated much basic Ti–OH groups at its surface by UV irradiation and subsequently adsorbed phosphate groups, such as H2PO4−, resulting in the formation of a new surface rich in the amount of the groups, which eventually enhanced the HA formation in 1.5SBF.