Photosensitization Reactions In Vitro and In Vivo

This review of Photochemistry and Photobiology summarizes articles published in 2010, and highlights progress in the area of photosensitization. The synthesis of conjugated photosensitizers is an area of interest where increasing water solubility has been a goal. Targeting infrared sensitizer absorption has been another goal, and relates to the practical need of deep tissue absorption of light. Photodynamic techniques for inactivating microbes and destroying tumors have been particularly successful. Biologically, singlet oxygen [1O2(1Δg)] is an integral species in many of these reactions, although photosensitized oxidations tuned to electron and hydrogen transfer (Type I) give rise to other reactive species, such as superoxide and hydrogen peroxide. How photoprotection against yellowing, oxygenation and degradation occurs was also an area of topical interest. This review highlights progress in the area of photosensitization. Singlet oxygen is a key species produced in many dye‐sensitized reactions, although electron‐ and hydrogen‐transfer reactions can give rise to other reactive oxygen species, such as hydroxyl radicals and superoxide. An area of topical interest is photoprotection against yellowing, oxygenation and degradation.