Electrochemical behaviour of Venlafaxine and its determination in pharmaceutical products using square wave voltammetry.

An electrochemical method for the determination of Venlafaxine in pharmaceutical formulations recently available on the European market is described. The electrochemical oxidation of Venlafaxine was studied at a HMDE electrode over a wide pH range (1.9-10.0) of buffered aqueous solutions using different potential sweep techniques. The results obtained showed that the best definition of the analytical signals was found in boric acid/potassium tetrahydroxoborate buffer at pH 8.7 using anodic stripping square wave voltammetry. Recovery trials were performed to assess the accuracy of results and these were compared to those provided by a HPLC technique according to the method described in literature and to the features of the pharmaceutical formulations. A relative deviation of < 0.2% was obtained. With the developed methodology, the limit of detection was 0.124 mg/l.