Oxidation kinetics of Iron(II) in Lipid Peroxidation Processes

The iron-mediated lipid peroxidation has been evaluated by focusing the investigations in two directions: (a) measuring the concentrations of oxidation products of lipids, and (b) investigation based on evaluation of susceptibility of lipids to oxidation upon their exposure to a source of free radicals. With the main aim to develop a reliable quantitative method for the measurement of peroxidation for in lipidic material, we produced a method of analysis, which has appeared applicable to different interdisciplinary studies of peroxidation of lipids. We have studied peroxidation of unsaturated fatty acids (LH) catalyzed by ferrous ions in buffering condition where autoxidation of Fe2+ and hydroxyl radicals generation does not occur. In these conditions, Fe2+ is oxidized only with preformed hydroperoxides of unsaturated fatty acids (LOOH) to form radical propagators, alkoxyl- and peroxyl- radicals. It is important to consider this process under conditions other than normal physiological ones since, in comparison with normal tissue ; tumors have relatively low pH levels. The lipid peroxidation was followed by determination of concentrations of LOOH by measurements of UV-diene conjugation and by the ferric thiocyanate method.