Detection of free radicals in UV-irradiated lens by spin trapping ESR.

Abstract

We have made an ESR study on the UV-photolysis of lens and identified the origins of free radicals involved in the initial photochemical process by spin trapping technique. Two spin adducts were detected on irradiation of canine lens in the presence of a spin trapping reagent (DMPO); a spin adduct of sulfur centered radical derived from glutathione and the protonated adduct of hydrated electron. A free radical mechanism of initial photochemical injury in UV-irradiated lens was discussed, comparing with a photolysis of tryptophan plus cysteine solution.