Simultaneous determination of felbamate and three metabolites in rat and dog plasmas by high-performance liquid chromatography.

An isocratic liquid chromatographic method employing one extraction step and a 150 mm x 4.6 mm I.D. Spherisorb ODS2, 3-microns HPLC column using UV-absorbance detection at 210 nm has been developed for the quantitation of felbamate and three felbamate metabolites in 0.100-ml aliquots of rat and dog plasmas. The linear quantitation range in rat plasma is 0.195-200 micrograms/ml for felbamate; 1.563-200 micrograms/ml for the p-hydroxy metabolite; 0.391-200 micrograms/ml for the 2-hydroxy metabolite; and 0.098-200 micrograms/ml for the monocarbamate metabolite. The linear quantitation range in dog plasma is 0.195-200 micrograms/ml for felbamate; 0.781-200 micrograms/ml for the p-hydroxy metabolite; 0.195-200 micrograms/ml for the 2-hydroxy metabolite; and 0.098-200 micrograms/ml for the monocarbamate metabolite.