Photosensitization by fluorescein dyes and tetracycline drugs at an oil/water interface.

Measurements were made of the changes that occur in the interfacial tension of isopropylbenzene when floating on water containing between 10(-5) and 10(-3) M of various fluorescein dyes and tetracycline drugs and irradiated for up to 240 min with ultraviolet light. Singlet oxygen was found to be an active intermediate in the reactions. The results are discussed in relation to adverse photosensitization in-vivo due to fluorescein dyes and tetracycline drugs.