Dye-Photosensitized Decomposition of 2-Mercaptobenzothiazole

It has been shown that dyes (eosin, erythrosine, Rose Bengal, fluorescein, Rhodamine C, Rhodamine 6G, 2,7-dichlorofluorescein, Methylene Blue, and Acridine Orange) sensitize the decomposition of 2-mercaptobenzothiazole in aqueous solutions. The quantum yields of photosensitized decomposition of 2-mercaptobenzothiazole depend linearly on the quantum yields of dye triplets. As shown by pulse photolysis, the triplet state of the dyes (eosin, erythrosine, and Rose Bengal) is quenched by 2-mercaptobenzothiazole. A mechanism has been suggested for the photosensitization of 2-mercaptobenzothiazole decomposition by irradiation of the dyes.