Evidence for hydroxyl radicals as an active species generated from Udenfriend's reagent

Abstract

The inhibitory effect of six aliphatic alcohols, which are typical OH radical scavengers, on the yield of phenol in the oxidations of benzene with Fenton's (Fe^II+ H₂O₂) and Udenfriend's (Fe^II+ EDTA + O₂+L-ascorbic acid) reagents has been examined. In both systems, these alcohols trap OH radicals effectively, as expected from the rate constants for the reactions of OH radical with benzene (k_B) and the alcohols (k_A), indicating that the active species generated from Udenfriend's reagent is OH radical. The Udenfriend oxidation of thymine in the presence of these alcohols gives further evidence for the generation of OH radical.