Molecular oxygen radicals are responsible for many problems like aging, cancer, lipid peroxidation, protein denaturation, oxidative stress etc., We present a comprehensive electrochemical investigation of the dissolved oxygen in DMSO containing 0.1 M TBAP as the supporting electrolyte. Different electrochemical techniques such as cyclic voltammetry, chronoamperometry and chronopotentiometry were used to extract heterogeneous kinetics and chemically coupled reaction kinetics related to the O-2 radicals. The experimentally determined parameters obtained through different methods were further confirmed through digital simulation (DIGISIM). Heterogeneous electron transfer rate constant (k(0)) was determined by three different methods, Nicholson & Shain, Gileadi, and the Kochi methods. The calculated k(0) values are different from the previously cited values. (C) 2016 Elsevier B.V. All rights reserved.