Rapid quantitation of testosterone hydroxyl metabolites by ultra-performance liquid chromatography and mass...

A rapid and sensitive ultra-performance liquid chromatography and mass spectrometry (UPLC/MS) method was developed to simultaneously quantify seven monohydroxyl testosterone metabolites (16alpha-, 2alpha-, 7alpha-, 6alpha-, 2beta-, 6beta-, and 16beta-hydroxyl testosterones) in rat liver microsomes. The UPLC system used a short 1.7-microm particle size column coupled to a Sciex 4000 Q trap in multiple reaction monitor (MRM) mode. All hydroxyl testosterones were resolved within 2.5 min. A 4-day validation was performed to determine the linearity, repeatability, reproducibility and accuracy of the method in rat liver microsomes. This method is applicable to the measurement of the testosterone hydroxylase activity in biological matrices such as the liver microsome incubates.