The effect of inhibitors on the radical formation in aqueous solutions of ascorbic acid

The rate of free radical formation in aqueous solutions of ascorbic acid in the presence of chelating agents was measured by the ESR-stopped-flow method. Addition of ethylenediamine tetraacetate and trimetaphosphoric acid to the ascorbic acid-oxygen system results in only a minimal change in the rate of ascorbate free radical formation compared to that in absence of inhibitors. Evidence suggests that radical formation arises via secondary reactions involving products.