Photocatalytic Inactivation Effect of Gold-DopedTiO2(Au/TiO2) Nanocomposites on Human Colon Carcinoma LoVo Cells

Abstract

The photocatalytic inactivation effecting of gold-dopedTiO2(Au/TiO2) nanocomposites on human colon carcinoma LoVo cells was investigated for the first time. The Au/TiO2samples containing different amounts of Au (1–4 wt%) were prepared by deposition-precipitation (DP) method. These synthesized Au/TiO2nanocomposites were characterized by transmission electron microscopy (TEM) and inductively coupled plasma atomic emission spectroscopy. It was found that the photocatalytic inactivation effect ofTiO2nanoparticles on LoVo cancer cells could be greatly improved by the surface modification of Au nanoparticles. Furthermore, the loading amount of Au on the surface ofTiO2nanoparticles affects the photocatalytic inactivation efficiency strongly, and it was found that the most efficient nanocomposites wereTiO2nanoparticles doped with 2 wt% Au. When 50μg/mL 2 wt% Au/TiO2nanocomposites were used, all of the LoVo cancer cells were killed under the irradiation of UV light (λmax= 365 nm, Intensity = 1.8 mW/cm2) within 100 minutes. But for 50μg/mLTiO2nanoparticles, only 40% cancer cells were killed under the same condition.