Simultaneous and stereospecific analysis of warfarin oxidative metabolism using 2D LC/Q-TOF.

Background: Warfarin is a widely used racemic anticoagulant with narrow therapeutic range and wide interindividual response to treatment. This is due to the extensive and differential clearance of R- and S-warfarin with the involvement of several polymorphic CYP450 enzymes resulting in the formation of several stereoisomeric oxidative metabolites.

Results: A stereospecific 2DLC/Q-TOF method was developed for the simultaneous identification and quantitation of hydroxylated warfarin metabolites from a single sample analysis. Using this method metabolites from rat microsomal and plated hepatocyte incubations with R-, S- and (R/S)-warfarin were estimated.

Conclusion: Multiheart cutting with high resolution MS and MS/MS analysis is suggested as a viable approach for achiral-chiral separation of metabolites of warfarin and other chiral or prochiral drugs.