[Determination of doping in human urine by gas chromatography-high resolution mass spectrometry].

A method was evaluated for determination of twenty-one doping (including nandrolone, boldenone and methandienone) in human urine by gas chromatography-high resolution mass spectrometry. Samples were prepared by liquid-liquid extraction, concentrated, TMS derivatization and limit of detection at ng x mL(-1) by MID/GC/HRMS. According to the code of the World Anti-Doping Agency (WADA), precision and recoveries of the procedure were evaluated by replicate analysis (n = 6), the recoveries in the range of 66%-103%, with the RSD below 10.0%. The precision within the day of the method with three different concentrations was also determined RSD were less than 9.5%, 10.0% and 9.7%.

Metabolism of methandrostenolone in the horse: a gas chromatographic-mass spectrometric investigation of phase I and phase II metabolism.

The phase I and phase II metabolism of the anabolic steroid methandrostenolone was investigated following oral administration to a standardbred gelding. In the phase I study, metabolites were isolated from the urine by solid-phase extraction, deconjugated by acid catalysed methanolysis and converted to their O-methyloxime trimethylsilyl derivatives. GC-MS analysis indicated the major metabolic processes to be sequential reduction of the A-ring and hydroxylation at C6 and C16. In the phase II study, unconjugated, beta-glucuronidated and sulfated metabolites were fractionated and deconjugated using a combination of liquid-liquid extraction, enzyme hydrolysis, solid-phase extraction and acid catalysed methanolysis. Derivatization followed by GC-MS analysis revealed extensive conjugation to both glucuronic and sulfuric acids, with only a small proportion of metabolites occurring in unconjugated form.

Comparison of sensitivity between gas chromatography-low-resolution mass spectrometry and gas chromatography-high-resolution mass spectrometry for determining metandienone metabolites in urine.

In doping control laboratories the misuse of anabolic androgenic steroids is commonly investigated in urine by gas chromatography-low-resolution mass spectrometry with selected ion monitoring (GC-LRMS-SIM). By using high-resolution mass spectrometry (HRMS) detection sensitivity is improved due to reduction of biological background. In our study HRMS and LRMS methods were compared to each other. Two different sets were measured both with HRMS and LRMS. In the first set metandienone (I) metabolites 17alpha-methyl-5beta-androstan-3alpha,17beta-dio l (II), 17-epimetandienone (III), 17beta-methyl-5beta-androst-1-ene-3alpha,17alpha-diol (IV) and 6beta-hydroxymetandienone (V) were spiked in urine extract prepared by solid-phase extraction, hydrolysis with beta-glucuronidase from Escherichia coli and liquid-liquid extraction. In the second set the metabolites were first spiked in blank urine samples of four male persons before pretreatment. Concentration range of the spiked metabolites was 0.1-10 ng/ml in both sets. With HRMS (resolution of 5000) detection limits were 2-10 times lower than with LRMS. However, also with the HRMS method the biological background hampered detection and compounds from matrix were coeluted with some metabolites. For this reason the S/N values of the metabolites spiked had to be first compared to S/N values of coeluted matrix compounds to get any idea of detection limits. At trace concentrations selective isolation procedures should be implemented in order to confirm a positive result. The results suggest that metandienone misuse can be detected by HRMS for a prolonged period after stopping the intake of metandienone.

Long-term detection and identification of metandienone and stanozolol abuse in athletes by gas chromatography-high-resolution mass spectrometry.

The misuse of anabolic androgenic steroids (AAS) in human sports is controlled by gas chromatography-mass spectrometric analysis of urine specimens obtained from athletes. The analysis is improved with modern high-resolution mass spectrometry (HRMS). The detection and identification of metabolites of stanozolol (I) [3'-hydroxystanozolol (II) and 4 beta-hydroxystanozolol (III)] and metandienone (IV) I17 beta-methyl-5 beta-androst-1-ene-3 alpha,17 alpha-diol (V) and 18-nor-17,17-dimethyl-5 beta-androsta-1,13-dien-3 alpha-ol (VI)] with GC-HRMS at 3000 resolution yielded a large increase in the number of positive specimens. A total of 116 anabolic steroid positives were found in this laboratory in 1995 via GC-MS and GC-HRMS screening of 6700 human urine specimens collected at national and international sporting events and at out-of-competition testing. Of the 116 positive cases, 41 were detected using conventional (quadrupole) GC-MS screening. The other 75 positives were identified via GC-HRMS screening. To confirm the HRMS screening result, the urine sample was reanalyzed using a specific sample workup procedure to selectively isolate the metabolites of the identified substance. II and III were selectively isolated via immunoaffinity chromatography (IAC) using an antibody which was prepared for methyltestosterone and shows high cross reactivity to II and III. V and VI were isolated using high-performance liquid chromatography (HPLC) fractionation.

Detection of methandienone (methandrostenolone) and metabolites in horse urine by gas chromatography-mass spectrometry.

The metabolic transformation of methandienone (I) in the horse was investigated. After administration of a commercial drug preparation to a female horse (0.5 mg/kg), urine samples were collected up to 96 h and processed without enzymic hydrolysis. Extraction was performed by a series of solid-liquid and liquid-liquid extractions, thus avoiding laborious purification techniques. For analysis by gas chromatography-mass spectrometry, the extracts were trimethylsilylated. Besides the parent compound I and its C-17 epimer II, three monohydroxylated metabolites were identified: 6 beta-hydroxymethandienone (III), its C-17 epimer (IV) and 16 beta-hydroxymethandienone (V). In addition, three isomers of 6 beta,16-dihydroxymethandienone (VIa-c) were discovered. Apparently, reduction of the delta 4 double bond of 16 beta-hydroxymethandienone (V) in the horse yields 16 beta,17 beta-dihydroxy-17 alpha-methyl-5 beta-androst-1-en-3-one (VII). Reduction of the isomers VIa-c results in the corresponding 6 beta,16,17-trihydroxy-17-methyl-5 beta-androst-1-en-3-ones (VIIIa-c). The data presented here suggest that screening for the isomers of VI and VIII, applying the selected-ion monitoring technique, will be the most successful way of proving methandienone administration to a horse.

Studies on anabolic steroids. V. Sequential reduction of methandienone and structurally related steroid A-ring substituents in humans: gas chromatographic-mass spectrometric study of the corresponding urinary metabolites.

The biotransformation of methandienone (17 beta-hydroxy-17 alpha-methylandrosta-1,4-dien-3-one) in human adults, more particularly the sequential reduction of its A-ring substituents, was investigated by gas chromatography-mass spectrometry. Two pairs of 17-epimeric tetrahydro diols resulting from the stereoselective reduction of the delta 4- and 3-oxo groups and of the delta 1-function were characterized. The major diols were 17 alpha-methyl-5 alpha-androstane-3 alpha,17 beta-diol and 17 alpha-methyl-5 beta-androstane-3 alpha,17 beta-diol, which were both excreted in the conjugate fraction in a 1:3.8 ratio. The immediate metabolic precursors of the 5 beta-diol, namely 17 beta-hydroxy-17 alpha-methyl-5 beta-androsta-1-en-3-one and 17 alpha-methyl-5 beta-androsta-1-en-3 alpha,17 beta diol and their corresponding 17-epimers, were also identified in post-administration urine samples. These data indicated that reduction of methandienone A-ring substituents proceeds according to the sequence. delta 4-, 3-oxo- and delta 1-. The A-ring reduction products of the structurally related steroids mestanolone, 17 alpha-methyltestosterone and oxymethone were also characterized and provided further analytical and metabolic evidence supporting the proposed route of methandienone A-ring reduction. It was also demonstrated using synthetic 17 beta-sulfate conjugates of methandienone and 17 alpha-methyltestosterone that their corresponding 17-epimers are formed by nucleophilic substitution by water of the labile sulfate moiety. The steroidal metabolites were identified on the basis of their characteristic mass spectral features and by comparison with authentic reference standards. Metabolic pathways accounting for the occurrence of the metabolites of interest in post-administration urine samples are proposed.

Gas chromatographic and capillary column gas chromatographic--mass spectrometric determination of synthetic anabolic steroids. I. Methandienone and its metabolites.

The determination of methandienone (I) (17 alpha-methyl-17 beta-hydroxyandrosta-1,4-dien-3-one) in human urine by gas chromatography and capillary column gas chromatography--mass spectrometry has been studied. After oral administration to man two major metabolites were detected, the structures of which have been identified as 17-epi-methandienone (II) and 6 beta-hydroxy-17-epi-methandienone (III). These metabolites are exclusively excreted in the unconjugated form. At least two more metabolites are extractable from the free fraction of the urine but no measurable amounts of I itself were found. The rate of metabolism and urinary excretion seems to be reasonably fast. The total amount of recovered I in the form of the metabolites II and III is about 5%. Extraction and clean-up procedures and chromatographic details are presented.