An Aromatic Hydroxylation Assay for Hydroxyl Radicals Utilizing High-Performance Liquid Chromatography (HPLC). Use to Investigate the Effect of Edta on the Fenton Reaction

A highly sensitive HPLC method for the separation of hydroxylation products derived from the attack of hydroxyl radical upon phenol is described. Catechol and hydroquinone are the major hydroxylation products formed, with little resorcinol. The effect of EDTA upon hydroxyl radical generation from an iron (H)-H2O2 system is shown to depend upon the order of addition of chelator and metal ion to the reaction mixture, the ratio [iron salt]/[chelator] and the presence or absence of a phosphate buffer. Reasons for these different effects are discussed.