LC determination and purity evaluation of nefazodone HCl in bulk drug and pharmaceutical formulations

A simple. selective and reproducible reversed-phase liquid chromatography ( LQ method has been developed for the quantitative determination of nefazodo ne hydrochloride (I) in the presence of its related impurities. namely 5-et hyl-4-(2-phenoxyethyl)-2H-1,2,4-triazol-3-(4H)one (II), 1-3-chlorophenyl)-4 -(3-chloropropyl) piperazine hydrochloride (III) and 1,1(1)-trimethylene-bi s[4-(3-chlorophenyl) piperazine] hydrochloride (IV). The separation was ach ieved using an Inertsil ODS-3V (250 x 4.6 mm(2)) column and a mobile phase comprising 0.05 M KH2PO4 (pH 3.0), acetonitrile and methanol in the ratio 5 0:40:10 (v/v/v). The method has been completely validated and proven to be rugged. The limit of detection and limit of quantification for impurities I I, III and IV were found to be 50, 79 and 91 ng/ml, and 152, 240 and 280 ng /ml, respectively. The intra- and inter-day assay precision of the method w as within 1.2% relative standard deviations, The developed method was appli ed to the pharmaceutical dosage form (Tablet, Serzone-R) and the percentage recoveries ranged from 99.1 to 100.7. The percentage recovery of impuritie s ranged from 96.2 to 108.9, The stability studies were performed for nefaz odone solution placed on laboratory bench and in the refrigerator for 60 da ys. The method was proved to be stability indicating in solution. (C) 2001 Elsevier Science B.V. All rights reserved.