[5] Deoxyribose assay for detecting hydroxyl radicals

Publisher Summary This chapter discusses the deoxyribose assay, and the practical application of the method. Iron ions might play a role in the deoxyribose assay via formation of other species, such as the ferryl or perferryl radical, whose properties are different from that of hydroxyl (•OH). However, no real evidence has been found that ferryl or the perferryl species exist in Fenton systems at physiological pH. Use of Fe(III)-EDTA in the presence of a reducing agent, such as ascorbate or the superoxide radical from the xanthine-hypoxanthine system mimics the conditions of ionizing radiation. The de-oxyribose assay has been adapted to assess the ability of food additives and nutrient components to act as pro-oxidants and hence mediate damage to the food matrix. The deoxyribose method remains an easy-to-use laboratory tool. When performed with an understanding that the inherent mechanisms involved are complex, the assay allows for (1) measuring rate constants for reactions with •OH and (2) assessing the iron-binding ability of the compound being tested.