Simultaneous quantification of cholesterol and its CYP3A4 dependent metabolite 4ß-OH-cholesterol with one analytical method (LC–MS/MS).
No further derivatization needed; i.e. direct determination (established is so far the formation of piconyl esters).
Similar or even higher sensitivity compared to previously published methods and considerably faster chromatographic run time than available methods (8 min vs. 10–30 min).
20">Comprehensive method validation according to current bioanalytical guidelines.
Application of the method to monitor induction effects of rifampicin in human and foals.