DETERMINATION OF DICLOFENAC SODIUM, FAMOTIDINE AND KETOROLAC TROMETHAMINE BY FLOW-INJECTION ANALYSIS USING DICHLORONITROPHENOL

Diclofenac sodium, famotidine and ketorolac tromethamine were determined by flow injection analysis (FIA) with spectrophotometric detection. The sample solutions (5-50 mug ml-1 of diclofenac sodium, 10-80 mug ml-1 of famotidine and 10-120 mug ml-1 of ketorolac tromethamine) in methanol were injected into a flow system containing 0.01% (w/v) of 2,4,dichloro-6-nitrophenol (DCNP) in methanol. The colour produced due to the formation of a charge transfer complex was measured with a spectrophotometric detector set at 450 nm. A sampling rate of 40 per hour was achieved with high reproducibility of measurements (RSD below 1.6%). The FIA method was applied to the determination of diclofenac sodium, famotidine and ketorolac tromethamine in pharmaceutical formulations.