High-performance liquid chromatographic determination of a new pyrazoloquinoline type benzodiazepine receptor antagonist and its hydroxy metabolite.

A rapid high-performance liquid chromatographic (HPLC) method for the determination of the novel benzodiazepine receptor antagonist 2-phenylpyrazolo[4,3-c]quinolin-3(5H)-one (CGS 8216) and its hydroxy metabolite is described. The method involves a solid-phase extraction with C18 disposable columns and quantification by HPLC with UV-detection. In plasma 20 ng/ml of the antagonist and 10 ng/ml of metabolite can be measured with a coefficient of variation of about 10%. The high sensitivity and selectivity of the assay makes it suitable for use in pharmacokinetic studies.