Abstract des Autors

In this work, the metabolism of oxymesterone and mesterolone, two anabolic androgenic steroids (AAS), was investigated by application of a selected reaction monitoring gas chromatography–chemical ionization–triple quadrupole mass spectrometry (GC‐CI‐MS/MS) protocol for metabolite detection and identification. Correlations between AAS structure and GC‐CI‐MS/MS fragmentation behaviour enabled the search for previously unknown but expected AAS metabolites by selection of theoretical transitions for expected metabolites. Use of different hydrolysis protocols allowed for evaluation of the detection window of both phase I and phase II metabolites. For oxymesterone, a new metabolite, 18‐nor‐17β‐hydroxymethyl‐17α‐methyl‐4‐hydroxy‐androst‐4,13‐diene‐3‐one, was identified. It was detectable up to 46 days by using GC‐CI‐MS/MS, whereas with a traditional screening (detection of metabolite 17‐epioxymesterone with electron ionization GC‐MS/MS) oxymesterone administration was only detectable for 3.5 days. A new metabolite was also found for mesterolone. It was identified as 1α‐methyl‐5α‐androstan‐3,6,16‐triol‐17‐one and its sulfate form after hydrolysis with Helix pomatia resulted in a prolonged detection time (up to 15 days) for mesterolone abuse.