EPR Study of Visible Light-Induced ROS Generation by Nanoparticles of ZnO

• Published in: Journal of physical chemistry. C Vol. 113; no. 36; pp. 15997 - 16001
• Main Authors: Lipovsky, Anat, Tzitrinovich, Zeev, Friedmann, Harry, Applerot, Guy, Gedanken, Aharon, Lubart, Rachel
• Format: Journal Article
• Language: English
• Published: American Chemical Society 10.09.2009
• Subjects: C: Nanops and Nanostructures
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp904864g

Nanoparticles of ZnO have been shown to have marked antibacterial and anticancerous activities. The toxic effect of ZnO has been found to exist due to a reaction of the ZnO surface with water. In the present work electron-spin resonance measurements revealed that aqueous suspensions of small nanoparticles of ZnO produce increased levels of reactive oxygen species, namely hydroxyl radicals and singlet oxygen. Interestingly, a remarkable enhancement of the oxy radicals, was detected when the ZnO water suspension had been irradiated with blue (400−500 nm) light. The characterization of the mechanism of light-induced oxy radicals formation by ZnO nanoparticles would contribute to its use as a sterilization agent.