Abstract
A method for the simultaneous determination of CGS 10787B and its major, metabolite (CGS 12094) in plasma is described. The two compounds, and the internal standard (dichlorinated analog), are extracted from acidified plasma with ethyl acetate, taken to dryness, and reconstituted in chromatographic mobile phase. The analytes are determined automatically by high performance liquid chromatography in the reversed-phase mode as paired ions, using [N(Bu)4]+ as the counterion. The separation of the compounds is achieved on a 3u C-8 column, with detection at 254 nm.
Recovery and reproducibility assessments indicate good accuracy and precision over the range of 1.0 to 250 ug/ml for CGS 10787B and 1.0 to 100 ug/ml for CGS 12094.
The method has a limit of detection of 0.2 ug/ml for both compounds, and has been shown to be adequate for studying the disposition kinetics of CGS 10787B.