Investigation of the level of free-radical processes in substrates and biological samples using induced chemiluminescence

The possibility of using induced chemiluminescence for estimation of the substrate capacity for peroxidation under the action of hydroxyl radicals and for determination of the level of free-radical processes that occur in biological objects based on the analysis of organic hydroperoxides in a sample was investigated. For this purpose the light sum of chemiluminescence was measured during the three stages: upon introduction of Fe 2+ into the sample, during the Fenton reaction (introduction of Fe 2+ and H 2 O 2 ), and upon introduction of Fe 2+ after the Fenton reaction. The dependence of the light sum on concentration (dilution) of the sample was elucidated. It was shown that the light sum reached its maximum value at a certain dilution of the investigated substrate. The position of the maximum was determined by the concentration of oxidizing RH fragments, while the chemiluminescence light sum value in the maximum was determined by the fraction of the inhibitor, [InH]/[RH], and the fraction of organic hydroperoxides in the sample, [ROOH]/[RH].