LIQUID-CHROMATOGRAPHIC METHODS FOR FLUOXETINE HYDROCHLORIDE, ITS METAISOMER, AND RELATED-COMPOUNDS IN RAW-MATERIALS

Liquid chromatographic (LC) methods were developed for assay of fluoxe tine hydrochloride, its meta isomer, and 12 related compounds in drug raw materials, The method for assay and determination of the meta isom er requires an Exsil ODS-B column; a mobile phase consisting of tetrah ydrofuran, acetonitrile, and buffer; a flow rate of 1 mL/min; and dete ction at 214 nm, The method for related compounds specifies a Spheriso rb nitrile column; a mobile phase consisting of tetrahydrofuran, aceto nitrile, and buffer; a flow rate of 1 mL/min; and detection at 214 nm, The limits of quantitation in the presence of the drug are 0.1% for t he meta isomer and 0.05% or less for the related compounds, Assay prec ision was less than 1.0% on triplicate weighings, Drug contents of 4 r aw material samples were between 98.8 and 100.1%, Impurity levels in t he 4 samples ranged from 0.14 to 0.45%. In addition, one sample contai ned ca 0.13% of the meta isomer, A second analyst, using columns from different suppliers, obtained similar results.