Use of graphite polyurethane composite electrode for imipramine oxidation -: Mechanism proposal and electroanalytical determination

This work is aimed at the elucidation of the oxidation mechanism for the tricyclic antidepressant imipramine using electrochemical and quantum chemical studies. The excellent response obtained with the use of a rigid graphite-polyurethane composite electrode (GPU) provided the development of a new electroanalytical methodology, in 0.10 mol/L BR buffer (pH 7.0), employing square wave voltammetry. Detection and quantification limits of 4.60x10(-9) mol/L(1.5 mu g L) and 3.04x10(-7) mol/L (96 mu g L) were obtained. This methodology was tested in a commercial formulation of Tofranil (R) trademark and excellent recoveries were achieved by electrochemical (97.60 +/- 0.90%) and spectrophotometrical (87.10 +/- 0.90%) methods.