Enzymatic electrodes based on superoxide dismutase enzyme were developed. Using the superoxide dismutase enzyme sensor assembled according to the classical model, poor results were obtained, Results were improved by adopting a new way of assembling the biosensor using a cellulose triacetate layer in which thp SOB enzyme is entrapped and sandwiched between two gas-permeable membranes, or using a kappa-carrageenan el layer entrapping the, enzyme, sandwiched between an external gas permeable membrane and an internal cellulose acetate membrane, coupled in each case to the oxygen amperometric transducer. Results obtained by applying the newly developed biosensor to assaying hydrophobic compounds showing radical scavengring properties, operating in dimethylsulfoxide, were also satisfactory.