Assay of bropirimine in rat plasma by means of robotic solid-phase extraction and high-performance liquid...

A rapid and simple high-performance liquid chromatography (HPLC) method incorporating automated solid-phase extraction (SPE) is described for the determination of bropirimine, 2-amino-5-bromo-6-phenyl-4(3H)-pyrimidinone, in plasma samples from various species. Using an automated sample processor, plasma samples were loaded onto C18 SPE columns and the drug eluted with ethanol-methylene chloride (10:90, v/v). The extracts were analyzed by reversed-phase HPLC using a C8 column with a mobile phase consisting of acetonitrile-water-trifluoroacetic acid (20:80:0.1, v/v/v). The UV absorbance of the column effluent was monitored at a wavelength of 292 nm. Linear calibration curves were obtained in the range of 0.01 to 22 micrograms/ml. Precision (< or = 4% relative standard deviation) and accuracy (< or = 5% error) were acceptable at the concentrations evaluated. Application of this method to the quantitation of bropirimine in rat plasma for a toxicokinetic/bioavailability study is reported.