Electrochemical Oxidation of an Immunosuppressant, Mycophenolate Mofetil, and Its Assay in Pharmaceutical Formulations

Abstract

Electrochemical oxidation of mycophenolate mofetil (MMF) has been studied at a glassy carbon electrode in aqueous solution over a wide pH range. MMF was oxidized on glassy carbon electrode (GCE) by an irreversible process that was controlled mainly by diffusion. The irreversibility of the electrode process was verified by different criteria. A probable mechanism for electrochemical oxidation of MMF was proposed. Differential-pulse voltammogram of the drug showed two oxidation peaks at 0.631 V and at 0.921 V (verses SCE) in phosphate buffer of pH 6.0. This process could be used to determine MMF in the concentration range of 5.0×10−7 to 7.5×10−4 M with a limit of detection of 1.48×10−7 M. The method was successfully applied for the analysis of MMF in pure and dosage forms and in biological fluids.