Kinetic Spectrophotmetric Method for Quantitation of Rizatriptan Benzoate in Pharmaceutical Formulations

A simple, sensitive and accurate kinetic spectrophotometric method for the determination of Rizatriptan Benzoate in pure and dosage form is described. The method is based on spectro-photometrically monitoring the oxidation of the drug by a known excess of Chloramine-B in HCl medium using initial rate, fixed time and variable time method in HCl medium. The oxidized product exhibits a maximum absorption at 490nm. The apparent molar absorptivity and Sandell’s sensitivity values are in the range 2.97x104 to 0.0198 respectively. The proposed method has been successfully applied to the determination of RTB in commercial pharmaceutical formulations. Statistical comparison of the results with well established reported method shows agreement in terms of precision and accuracy.