Spectrophotometric Method For Estimation Of Some COX-2 Inhibitors In Pure From And In Pharmaceutical Formulations
Ultraviolet absorption spectrophotometric method for the estimation of celecoxib, rofecoxib, meloxicam and nimesulide in pure form and in pharmaceutical formulations has been developed. The solvents employed were 10% (v/v) aqueous dimethylsulfoxide for rofecoxib, 10% (v/v) aqueous dimethylformamide for meloxicam, 20% (v/v) aqueous acetonitrile for celecoxib and nimesulide. 0.1 N sodium hydroxide was also used as solvent for all the drugs except rofecoxib. All the solvents were found to give accurate, sensitive and reproducible results for the estimation of drugs in pure form. These solvent systems could also be used for the estimation of drugs from solid formulations. For the estimation of drugs in pure form, method involving the use of 0.1 N sodium hydroxide was found to be relatively more precise, economical and safer than the one involving the use of organic solvents. For the estimation of celecoxib, rofecoxib and meloxicam from the formulations, on the other hand, the use of organic solvents gave better results and should be preferred. For the estimation of nimesulide from formulations, however, again 0.1 N sodium hydroxidewas found to be a better solvent.