Photodynamic Activity of Ascorbic Acid-modified TiO2 Nanoparticles upon Visible Illumination (>550 nm)

Abstract
Though both TiO2 and ascorbic acid are noncytotoxic in the dark or under visible irradiation, ascorbic acid-modified TiO2 nanoparticles were found to exhibit efficient DNA and cancer cell damage ability under visible light irradiation, opening a new pathway for developing highly efficient PDT sensitizers.