DETERMINATION OF ANTIOXIDANT CAPACITY AND REACTIVITY USING HEMIN-CATALYZED LUMINOL CHEMILUMINESCENCE

摘要

The chemiluminescence of luminol can be induced by free radical and/or redox p-ocesses and the simplicity and sensitivity of this technique is an advantage in the development of analytical methods for the monitoring of free radical production or consumption,' Several of the methods used for measuring total antioxidant capacity of plasma or serum employ azoinitiators, due to their capacity to decompose, producing peroxyl radicals at a constant rate, and luminol chemiluminescence.2 Previously, our group has described a screening method for antioxidant potential determination based on luminol - hemin- hydrogen peroxide chemiluminescence.34 The emission depletion, caused by an antiradical compound added during the chemiluminescence decay was shown to be proportional to the number of reactive species trapped and the difference between the areas of the emission decay curves, obtained in the absence and the presence of the potential antioxidant, has been utilized as a measure for the antiradical capacity of the sample. The technique can therefore be used for the measurement of the antiradical capacity of pure compounds and complex mixtures.