Abstract

Development and validation of a regioselective, specific, stability indicating LC and assay method for zafirlukast

Author(s): Ch.Krishnaiah, B.J.Durga Prasad, V.Malathi, Gilla Goverdan, A.Raghupathi Reddy, Ramesh Kumar, K.Mukkanti

Zafirlukast is a selective and competitive orally-administered inhibitor of the cysteinyl leucotrienes and is currently indicated for the prophylaxis and treatment of chronic asthma.Asimple, rapid, and reliable LCmethod for the determination of ZAF in pharmaceutical drug substances and drug products was developed and validated. The influence of buffer concentration, buffer pH, organic modifier, column temperature, ion-pair reagent and injection volume was systemically investigated in octadecyl columns (ID 46 mm, length 25 cm, practical size 5 ìm). Optimum results were obtained with 10 mM potassiumbuffer, 5 mMof 1-decane sulphonic sodiumsalt at pH 4.0, and a column temperature of 27 °C. The detection wavelength was set at 220 nm. Themethodwas suitably validated with respect to linearity, limit of detection and quantification, accuracy, precision, selectivity, robustness and ruggedness. The linear calibration range had a LOQ of 1.5 ìg mL-1, and the limit of detection and quantificationwere 0.009 and 0.06 ìg mL-1, respectively, with a relative standard deviation of 6.7%. The proposedmethodwas applied for the determination of ZAF in its pharmaceutical drug substances and drug products. The results obtained from the developed method were compared to an LC method reported in the literature, and no significant statistical differences were found. Assay and RS methods were fully validated and a comparison wasmade. The results confirmthat the methods are highly suitable for their intended purpose.