Abstract
When compacts of the titania powders having high photocatalytic activities were light-illuminated beforehand in simulated body fluid (SBF) and subsequently held at 37 °C, the bonelike apatite crystals were formed on the surfaces. X-ray photoelectron spectroscopic analysis showed that basic Ti-OH groups, which induce the apatite nucleation, is formed abundantly at the negatively charged surface of titania by the light-illumination in SBF. Powder mixture compacts consisting of calcium carbonate composite containing fine-sized titania particles were prepared using a carbonation process. Bonelike apatite phase was formed on the compacts in SBF within 2 d. These findings indicate we are able to prepare novel bioactive materials controlled by photoexcitation and/or hybridization of titania.
