817-Application of short controlled drop-time polarography to the study of superoxide ion dismutation in aqueous solutions. Determination of the activity of superoxide dismutases

A short controlled drop-time mercury electrode was utilized to generate the superoxide ion, O2-, in aqueous solutions and to study the dismutation processes of this ion. In particular, by the method of the catalytic currents, it was possible to measure the activity of superoxide dismutases, a class of metallo-enzymes present in aerobic cells. The use of this electrode minimizes the contribution of the spontaneous dismutation of the O2- to the limiting currents and, as a consequence, it makes enzyme activity measurements possible down to physiological pH values. The advantages with respect to other physicochemical methods are discussed. © 1984