Assay of Flurbiprofen in Rat Plasma Using HPLC with Fluorescence Detection

A high performance liquid chromatographic (HPLC) method was developed for the determination of flurbiprofen in rat plasma. The method employs a smaller sample volume (0.05 mL) and involved deproteinization of the biological sample with 2.5 volumes of acetonitrile for the determination of flurbiprofen. Ten microliters of the supernatant was injected onto a C18 reverse phase column. The mobile phase employed was acetonitrile-water-phosphoric acid (600:400:0.5, v/v/v). The flow rate was 1.5 mL/min. The column effluent was monitored by fluorescence detection at excitation wavelength of 250 nm and emission wavelength of 285 nm. The retention time was 3.4 min. The detection limit in rat plasma was 50 ng/mL. The mean percentage recovery of the drug in the concentration range of 0.05–5 μg/mL was 95.14% while the mean of the inter-day coefficient of variation of the same concentration range was 1.37%. The method was simple, rapid and accurate for quantitation of flurbiprofen in rat plasma.