UV-VIS SPECTROPHOTOMETRIC METHOD FOR ESTIMATION OF PREGABALIN AND METHYLCOBALAMIN IN BULK AND CAPSULE DOSAGE FORM

Abstract

A simple, rapid, sensitive & specific UV-Vis spectrophotometric method has been developed for the estimation of Pregabalin & Methylcobalamin in bulk and capsule dosage form. The estimation was based upon measurement of absorbance of capsule in distilled water at λmax 351nm for Methylcobalamin and 617nm for Pregabalin after reacting with bromocresol green(BCG) which forms colored ion-pair complexes with the dye (drug/dye 1:1) in methanol The color was found to be stable for more than 2 hours. Beer Lambert’s law was obeyed over a concentration range of 2-10μg/ml for Pregabalin (r 2 = 0.995) & Methylcobalamin (r 2 = 0.994). The results of estimation in capsules were 100.80% & 100.24% by standard curve method and 99.07% and 99.47% by double point standardization of the label claim for Pregabalin & Methylcobalamin respectively. The method has been validated with respect to linearity, range, accuracy, precision, robustness and ruggedness. The excipients present in the formulations do not interfere with the assay procedure.