KINETIC AND SPECTROSCOPIC FEATURES OF SOME CAROTENOID TRIPLET STATES: SENSITIZATION BY SINGLET OXYGEN

作者：Michael A. J. Rodgers, Anne L. Bates · 发表于：Photochemistry and Photobiology · 年份：1980 · DOI：10.1111/j.1751-1097.1980.tb03742.x · 被引用次数：43 · 研究领域：Free Radicals and Antioxidants、Spectroscopy and Quantum Chemical Studies、Antioxidant Activity and Oxidative Stress

Abstract— Triplet‐triplet absorption spectra of a series of carotenoid pigments in benzene solution have been determined by pulse radiolysis experiments. The natural lifetimes in deaerated solution have also been measured. They fall in the range 2–10 µs as found for other carotenoids under similar conditions. Pulsed laser (337 nm) excitation of benzene solutions containing oxygen, carotenoid and a photosensitized molecule (anthracene) showed the generation of absorption spectra of the triplet states. These absorptions decayed by first order kinetics in such a way as to indicate that they were formed in reactions with singlet oxygen, itself generated by interaction with the anthracene triplet state. Bimolecular rate constants for energy transfer from O*2 (1△g), to carotenoid have been evaluated.