Reactions in imipramine-pyrocatechol violet and imipramine-iron(III) ion systems

Two methods for the determination of imipramine hydrochloride are presented . One method employs the liability of the imipramine tertiary amine group n itrogen atom to form ion-association complexes with organic compounds. The formed complex is insoluble in water but well soluble in organic solvents. This property is the base of a new extractive-spectrophotometric method for imipramine determination. The second method is based on the oxidation of i mipramine by iron(III) ions. Imipramine hydrochloride is oxidized by Fe(III ) ions at 75 degrees C with the formation of coloured products. Both reacti ons were followed spectrophotometrically by measuring the absorbance at 445 nm (extractive method) and at 670 nm (oxidative method). The methods have been successfully applied to the determination of imipramine in a liquid fo r injection. The results were compared with those obtained by the official procedure.