Production of superoxide ions by photosensitization of dyes

The formation of superoxide anions by photosentization of fluorescein and other aromatic molecules has been observed using the enzyme lactoperoxidase as detector. Aerobic photosensitization caused the formation of Compound III with a rate of formation directly proportional to light intensity. Yields were such that photosensitization could be used as a superoxide anion generating process. Superoxide dismutase was also successfully used to demonstrate the specific involvement of superoxide ions in this photoprocess.