Simultaneous identification of prednisolone and its ten metabolites in human urine by high performance liquid chromatography-tandem mass spectrometry

The use of prednisolone and prednisone is prohibited by the World Anti‐Doping Agency (WADA) due to their performance‐enhancing effect. The purpose of the present work was to explore the possibility of identification and detection of various metabolites of prednisolone by liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) in excretion study samples. Ten metabolites of prednisolone could be identified namely prednisone (11‐oxo metabolite) [M‐1], 6‐β‐OH‐prednisolone [M‐2], 20‐β‐OH‐prednisolone [M‐3], 20‐α‐OH‐prednisolone [M‐4], 20‐α‐OH‐prednisone [M‐5], 20‐β‐OH‐prednisone [M‐6], 2 tetrahydro epimers of 20‐β‐OH‐prednisolone [M‐7], 2 tetrahydro epimers of 20‐α‐OH‐prednisolone [M‐8], 2 tetrahydro epimers of 20‐β‐OH‐prednisone [M‐9], and 2 tetrahydro epimers of 20‐α–OH‐prednisone [M‐10]. Prednisolone was administered in 10‐, 20‐, and 40‐mg dosage to healthy volunteers to study detection of various metabolites. The parent, M‐1, M‐2, and M‐3 could be detected up to 72 h while rest of the metabolites were detectable up to 24 h after drug administration. The detection of newer metabolites of the drug can further be used for confirmatory purposes. Copyright © 2012 John Wiley & Sons, Ltd.