[Photodynamic activity and singlet oxygen].

Biofizika

Bakh Institute of Biochemistry, Russian Academy of Sciences, Lomonosov Moscow State University, Moscow, Russia.

Published: September 2004

The primary mechanisms for the photodynamic action of pigments and dyes, the principles of their division into mechanisms of type I and type II, and the role of these processes in biological systems are reviewed. Singlet oxygen is considered to be an indicator of the mechanisms of photodynamic reactions. The methods of its detection are described, which are based on the use of chemical traps, measurements of infrared phosphorescance at 1270 nm, and the registration singlet oxygen-sensitized delayed fluorescence caused by the summation of the energy of two singlet oxygen molecules by one dye molecule.

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