Spectrophotometric Determination of Reduced Nimesulide using 8- Hydroxyquinolinol Reagent in Pharmaceutical Preparations

A simple, sensitive and rapid spectrophotometric method has been developed for the determination of Nimesulide (NIME) in pure as well as in dosage form is described. The proposed method is based on the reduction of the nitro group of drug using a novel and versatile reduction system comprising iron metal and hydrochloric acid. The resulting amine was then diazotization and coupling 8-Hydroxyquinolinol in alkaline medium to form orange colored chromogene exhibiting absorbance maximum at 480 nm. Beer s law was obeyed in the concentration ranges 5 – 250 μg/10 ml, i.e. 0.5-25 μg/ml and the correlation coefficients is 0.9996 with a molar absorptivity of 1.378×10^4 l.mol^-1. cm^-1 and Sandell s sensitivity index of 0.022 μg.cm^-2 , a recovery of 99.36 to 101.64 and relative standard deviation of ±0.40 to ±1.24 %, depending on the concentration level. The method has been applied successfully to the determination of Nimesulide in pharmaceutical preparations.