SIMPLE SPECTROPHOTOMETRIC METHODS FOR ESTIMATION OF DRUGS AND PHARMACEUTICALS USING NBS-METHYL ORANGE DYE COUPLE

Simple. sensitive. cost-effective and selective methods are designed and developed for the oxidative indirect spectrophotometric determination of drugs and pharmaceuticals, viz.. Argatrobane Monohydrate (ARG), Bortezomib (BOR). Chloroquine Phospate (CHP). Granisetron HCl (GRA), Ibandronate Sodium (IBA) based on their reactivity towards n-bromo succinamide (NBS in excess). The method is based on the oxidation of drugs by n-bromo succinamide (excess) and estimating the amount of un-reacted NBS by Methyl Orange dye at lambda(max) 508 nm. The calibration curves obeyed Beer's law over the concentration range of 10-70 mu g mL(-1) (ARG). 8-56 mu g mL(-1) (BOR). 6-42 mu g mL(-1) (CHP). 4-28 mu g mL(-1) (GRA) & 5-35 mu g mL(-1) (IBA). This method has been applied for the determination of drugs in their pure form as well as in tablet formulations. Statistical analysis of the results using Student's t-test for accuracy and F-test for precision revealed no significant difference between the proposed methods and the literature method at the 95% confidence level with respect to accuracy and precision. The method has been validated in terms of guidelines of the International Council of Harmonization.