Study on cytotoxicity and photocatalytic properties of different titania/hydroxyapatite nanocomposites prepared with a combination of sol–gel and precipitation methods

Abstract

In the present study different titania/hydroxyapatite nanocomposites were successfully synthesized via a combination of sol–gel and precipitation methods. Titanium-tetra-isopropoxide, 1-propanol, calcium nitrate tetra-hydrate and orthophosphoric acid were the starting materials. In order to characterize samples, several techniques such as XRD, Raman spectroscopy, FE-SEM, and BET–BJH were used. The photocatalytic activity of nanocomposites was investigated by photodegradation of 10 mg L−1 methylene blue aqueous solution under UV irradiation for 120 min. The dye adsorption of titania in darkness was enhanced from 2.5 to 11.6% for 40 wt% titania/hydroxyapatite nanocomposite. The best photocatalytic efficiency was obtained for 50 wt% titania/hydoxyapatite nanocomposite (90.5%), and the reaction rate constant increased from 0.0186 min−1 for pure titania to 0.0213 min−1 for 50 wt% titania/hydroxyapatite nanocomposite. The improvement in photoactivity of nanocomposite samples is due to high adsorption of dye molecules on hydroxyapatite surfaces and less agglomeration of titania nanopoarticles, for which the last is in accordance with FE-SEM and BET results. The toxic potentials of TiO2 and 50 wt% titania/hydroxyapatite nanocomposite on human normal cell lines were also examined, and the results showed their insignificant effects on HUVEC proliferation.