HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC DETERMINATION OF THE INSULIN SENSITIZING AGENT DRF-2189 IN RAT PLASMA

A high-performance liquid chromatographic method for the determination of DRF-2189, using troglitazone as internal standard, is described. A dichloromethane-ethyl acetate solvent mixture (6:4, v/v) was used as the extraction solvent. A Kromasil C-18 column with a mobile phase con sisting of 0.05 M phosphate buffer-acetonitrile-methanol (22.5:37.5:40 ) (pH 5.0) was used at a flow-rate of 1.0 ml/min. The eluate was monit ored by using fluorescence detection with excitation and emission wave lengths at 292 nm and 325 nm, respectively. Ratio of peak area of anal yte to internal standard was used for quantification of plasma samples . Using this method, the absolute recovery of DRF-2189 from rat plasma was > 95% and the limit of quantitation was 50 ng/ml. The intra-day r elative standard deviation (R.S.D.) ranged from 1.74 to 7.24% at 1 mu g/ml and 1.86 to 3.83% at 10 mu g/ml. The inter-day R.S.D.s were 8.34 and 4.91% at 1 and 10 mu g/ml, respectively. The method was applied to measure plasma concentrations of DRF-2189 in pharmacokinetic studies in Wistar rats. (C) 1998 Elsevier Science B.V.