Determination of a novel xanthine derivative, MKS 213–492, in plasma by high-performance liquid chromatography with electrochemical detection

A reversed-phase liquid chromatographic method with coulometric detection has been developed for the determination of free MKS 213–492 (a novel xanthine derivative) in plasma. This method is based on a simple and rapid plasma extraction procedure using precolumn-switching. The oxidation of this pharmacologically active xanthine derivative was optimized with respect to applied potential, pH of mobile and rinsing phase and rinsing time. The detection limit for MKS 213–492 was found to be 54 pg/injection.