SIMPLIFIED HPLC METHOD WITH SPECTROPHOTOMETRIC DETECTION FOR THE ASSAY OF CLOFIBRIC ACID IN RAT PLASMA

A simple and rapid reversed-phase HPLC method for the assay of clofibr ic acid in rat plasma is presented. After a simultaneous deproteinizat ion-extraction step of a 200 mu L plasma sample with a solution of pro pyl paraben in acetonitrile, the clear extract was injected onto a Mic rosorb-MV C18 chromatographic column and eluted with 1% acetic acid in acetonitrile-water (45:55) at the rate of 0.8 mL/min. At the detectio n wavelength of 230 nm, clofibric acid and propyl paraben, the interna l standard, eluted at 7.0 min and 5.5 min, respectively. Peak response s were linearly related to concentrations of clofibric acid in the ran ge 1.5-30 mu g/mL, with a minimum detectable concentration of analyte of 75 ng on-column. Recoveries of clofibric acid from plasma samples s piked at 1.5-30 mu g/mL levels of analyte were >94% (range 94.6-99%). The proposed method was easily applied to tile determination of the pl asma plasma levels of clofibric acid derived from the oral and intrape ritoneal administrations of clofibrate as a liquisolid compact and as the contents of a commercial soft gelatin capsule to rats.