Screening of free 17-alkyl-substituted anabolic steroids in human urine by liquid chromatography-electrospray ionization tandem mass spectrometry

A qualitative liquid chromatography-electrospray ionization tandem mass spectrometry method was developed for screening of the abuse of 4-chlorodehydromethyltestosterone, danazol, fluoxymesterone, formebolone, metandienone, oxandrolone, and stanozolol. The introduced method measures simultaneously nine different 17-alkyl-substituted anabolic androgenic steroids or their unconjugated metabolites in human urine, using methyltestosterone as an internal standard. Sample preparation involved one-step liquid extraction. Liquid chromatographic separation was achieved on a reversed-phase column with methanol-water gradient containing 5 mmol/l ammonium acetate and 0.01% (v/v) acetic acid. Compounds were ionized in the positive mode and detected by multiple reaction monitoring. All steroids within the study could be selectively detected in urine with detection limits of 0.1-2.0 ng/ml. The method showed good linearity up to 250 ng/ml with correlation coefficients higher than 0.9947. With simple and fast sample preparation, low limits of detection, and high selectivity and precision, the developed method provides advantages over the present testing methods and has the potential for routine qualitative screening method of unconjugated 17-alkyl-substituted anabolic steroids in human urine.