Spectrophotometric determination of imipramine hydrochloride using ammonium peroxidisulfate and niobium(V) thiocyanate complex

Two methods for the determination of imipramine hydrochloride are presented . One method is based on the oxidation of imipramine using ammonium peroxid isulfate with the formation of colored products. This property is the basis of a new spectrophotometric method for imipramine determination. The secon d method employs the liability of the imipramine tertiary amine group nitro gen atom to form ion-pair compound with niobium(V) thiocyanate complex. The formed ion associate is insoluble in water but well-soluble in organic sol vents. Both reactions were followed spectrophotometrically by measuring the absorbances at 658 nm (oxidative method) and at 350 nm (extractive method) . The methods have been successfully applied to the determination of imipra mine in pharmaceutical preparations. The results were compared with those o btained by the official procedure.