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Ho HSM, Ho ENM, Wong WT. Endogenous nature of estra-4,9-diene-3,17-dione in entire male horses. Drug Test Anal 2024. [PMID: 38532598 DOI: 10.1002/dta.3685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 02/29/2024] [Accepted: 03/07/2024] [Indexed: 03/28/2024]
Abstract
Estra-4,9-diene-3,17-dione (dienedione) is an anabolic androgenic steroid (AAS) sold as a bodybuilding supplement. It is prohibited in both human and equine sports. With no report of 4,9-diene configuration in endogenous steroids, dienedione has long been considered a synthetic AAS. Nevertheless, the reoccurring detection of dienedione in colt (entire male horse) urine samples lead to the investigation of its possible endogenous nature in horses. This paper describes (i) the detection of naturally occurring dienedione in colts, (ii) the conjugation study of dienedione and (iii) the population study of free and glucuronide-conjugated dienedione in colt urine. Qualitative and quantitative analyses of dienedione content in colt urine were performed, employing liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Qualitative analyses showed that dienedione was endogenous in colt urine and mainly in the form of glucuronide conjugates. Glucuronidation of dienedione was believed to happen at 3-enol leading to dienedione-3-glucuronide. Upon the population study of free and glucuronide-conjugated dienedione in colt urine samples (n = 175), the mean ± SD was determined to be 2.5 ± 3.5 ng/ml. The population data fitted a normal distribution after a fifth root transformation with the exclusion of one outlier by Grubb's test. A possible in-house threshold was proposed at 30 ng/ml of free and glucuronide-conjugated dienedione in colt urine associated with a risk factor of 1 in 14,269 (with a degree of freedom of 173). This is the first report of endogenous dienedione in entire male horses and the approach for controlling its potential misuse by using a threshold is also presented.
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Affiliation(s)
- Helen S M Ho
- Department of Applied Biology and Chemical Technology, Hong Kong Polytechnic University, Hong Kong, China
| | - Emmie N M Ho
- Racing Laboratory, The Hong Kong Jockey Club, Hong Kong, China
| | - Wing-Tak Wong
- Department of Applied Biology and Chemical Technology, Hong Kong Polytechnic University, Hong Kong, China
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2
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Göschl L, Gmeiner G, Gärtner P, Steinacher M, Forsdahl G. Detection of DHCMT long-term metabolite glucuronides with LC-MSMS as an alternative approach to conventional GC-MSMS analysis. Steroids 2022; 180:108979. [PMID: 35183566 DOI: 10.1016/j.steroids.2022.108979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 01/19/2022] [Accepted: 02/07/2022] [Indexed: 10/19/2022]
Abstract
Dehydrochloromethyltestosterone (DHCMT) is one of the most detected illicit used anabolic-androgenic steroids in professional sports. Therefore, a fast and accurate analysis of this substance is of great importance for a constructive fight against doping abuse. The conventional method for the analysis of this drug, GC-MSMS, is very sensitive and selective but also very time- and resource-consuming. With the presented work, a new approach for simple detection with LC-HRMSMS without any sample preparation is introduced. The method is based on the direct analysis of two newly described phase-II metabolites of the DHCMT long-term metabolite 4-chloro-18-nor-17β-hydroxymethyl-17α-methyl-5β-androst-13-en-3α-ol (M3). LC-HRMSMS, GC-MSMS, fractionation and derivatization experiments are combined to identify and characterize for the first time two different glucuronide-acid conjugates of this metabolite in positive human urine samples. In addition, a third glucuronide metabolite was identified, however without isomeric structure determination. The detection of these metabolites is particularly interesting for confirmation analyses, as the method is rapid and requires little sample material.
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Affiliation(s)
- Lorenz Göschl
- Doping Control Laboratory, Seibersdorf Labor GmbH, Seibersdorf, Austria; Department of Pharmacy, University of Tromsø - The Arctic University of Norway, Tromsø, Norway.
| | - Günter Gmeiner
- Doping Control Laboratory, Seibersdorf Labor GmbH, Seibersdorf, Austria
| | - Peter Gärtner
- Institute of Applied Synthetic Chemistry, Technical University of Vienna, Vienna, Austria
| | - Michael Steinacher
- Institute of Applied Synthetic Chemistry, Technical University of Vienna, Vienna, Austria
| | - Guro Forsdahl
- Doping Control Laboratory, Seibersdorf Labor GmbH, Seibersdorf, Austria; Department of Pharmacy, University of Tromsø - The Arctic University of Norway, Tromsø, Norway
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3
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Huml L, Tauchen J, Rimpelová S, Holubová B, Lapčík O, Jurášek M. Advances in the Determination of Anabolic-Androgenic Steroids: From Standard Practices to Tailor-Designed Multidisciplinary Approaches. SENSORS (BASEL, SWITZERLAND) 2021; 22:4. [PMID: 35009549 PMCID: PMC8747103 DOI: 10.3390/s22010004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/06/2021] [Accepted: 12/14/2021] [Indexed: 12/12/2022]
Abstract
Anabolic-androgenic steroids (AASs), a group of compounds frequently misused by athletes and, unfortunately, also by the general population, have lately attracted global attention; thus, significant demands for more precise, facile, and rapid AAS detection have arisen. The standard methods ordinarily used for AAS determination include liquid and gas chromatography coupled with mass spectrometry. However, good knowledge of steroid metabolism, pretreatment of samples (such as derivatization), and well-trained operators of the instruments are required, making this procedure expensive, complicated, and not routinely applicable. In the drive to meet current AAS detection demands, the scientific focus has shifted to developing novel, tailor-made approaches leading to time- and cost-effective, routine, and field-portable methods for AAS determination in various matrices, such as biological fluids, food supplements, meat, water, or other environmental components. Therefore, herein, we present a comprehensive review article covering recent advances in AAS determination, with a strong emphasis on the increasingly important role of chemically designed artificial sensors, biosensors, and antibody- and fluorescence-based methods.
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Affiliation(s)
- Lukáš Huml
- Department of Chemistry of Natural Compounds, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, 16628 Prague, Czech Republic; (O.L.); (M.J.)
| | - Jan Tauchen
- Department of Food Science, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, 16500 Prague, Czech Republic;
| | - Silvie Rimpelová
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, 16628 Prague, Czech Republic;
| | - Barbora Holubová
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, 16628 Prague, Czech Republic;
| | - Oldřich Lapčík
- Department of Chemistry of Natural Compounds, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, 16628 Prague, Czech Republic; (O.L.); (M.J.)
| | - Michal Jurášek
- Department of Chemistry of Natural Compounds, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, 16628 Prague, Czech Republic; (O.L.); (M.J.)
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4
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Göschl L, Gmeiner G, Enev V, Kratena N, Gärtner P, Forsdahl G. Development and validation of a simple online‐SPE method coupled to high‐resolution mass spectrometry for the analysis of stanozolol‐N‐glucuronides in urine samples. Drug Test Anal 2020; 12:1031-1040. [DOI: 10.1002/dta.2805] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 04/01/2020] [Accepted: 04/11/2020] [Indexed: 01/24/2023]
Affiliation(s)
- Lorenz Göschl
- Doping Control Laboratory, Seibersdorf Labor GmbH Seibersdorf Austria
- Department of Pharmacy University of Tromsø – The Arctic University of Norway Tromsø Norway
| | - Günter Gmeiner
- Doping Control Laboratory, Seibersdorf Labor GmbH Seibersdorf Austria
| | - Valentin Enev
- Institute of Applied Synthetic Chemistry Technical University of Vienna Austria
| | - Nicolas Kratena
- Institute of Applied Synthetic Chemistry Technical University of Vienna Austria
| | - Peter Gärtner
- Institute of Applied Synthetic Chemistry Technical University of Vienna Austria
| | - Guro Forsdahl
- Doping Control Laboratory, Seibersdorf Labor GmbH Seibersdorf Austria
- Department of Pharmacy University of Tromsø – The Arctic University of Norway Tromsø Norway
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Blokland MH, van Tricht EF, van Ginkel LA, Sterk SS. Applicability of an innovative steroid-profiling method to determine synthetic growth promoter abuse in cattle. J Steroid Biochem Mol Biol 2017; 174:265-275. [PMID: 29030156 DOI: 10.1016/j.jsbmb.2017.10.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 10/08/2017] [Accepted: 10/09/2017] [Indexed: 12/20/2022]
Abstract
A robust LC-MS/MS method was developed to quantify a large number of phase I and phase II steroids in urine. The decision limit is for most compounds lower than 1ngml-1 with a measurement uncertainty smaller than 30%. The method is fully validated and was applied to assess the influence of administered synthetic steroids and beta-agonists on the steroidogenesis. From three animal experiments, clenbuterol, diethylstilbestrol and stanozolol, the steroid profiles in urine of bovine animals were compared before and after treatment. It was demonstrated that the steroid profiles were altered due to these treatments. A predictive multivariate model was built to identify deviations from normal population steroid profiles. The abuse of synthetic steroids can be detected in urine samples from bovine animals using this model. The samples from the animal experiments were randomly analysed using this method and predictive model. It was shown that these samples were predicted correctly in the exogenous steroids group.
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Affiliation(s)
- M H Blokland
- RIKILT Wageningen University & Research, P.O. Box 230, Wageningen, The Netherlands.
| | - E F van Tricht
- RIKILT Wageningen University & Research, P.O. Box 230, Wageningen, The Netherlands
| | - L A van Ginkel
- RIKILT Wageningen University & Research, P.O. Box 230, Wageningen, The Netherlands
| | - S S Sterk
- RIKILT Wageningen University & Research, P.O. Box 230, Wageningen, The Netherlands
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Abushareeda W, Lyris E, Kraiem S, Wahaibi AA, Alyazidi S, Dbes N, Lommen A, Nielen M, Horvatovich PL, Alsayrafi M, Georgakopoulos C. Gas chromatographic quadrupole time-of-flight full scan high resolution mass spectrometric screening of human urine in antidoping analysis. J Chromatogr B Analyt Technol Biomed Life Sci 2017; 1063:74-83. [DOI: 10.1016/j.jchromb.2017.08.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 08/10/2017] [Accepted: 08/14/2017] [Indexed: 11/28/2022]
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Wang Z, Zhou X, Liu X, Dong Y, Zhang J. A novel HPLC-MRM strategy to discover unknown and long-term metabolites of stanozolol for expanding analytical possibilities in doping-control. J Chromatogr B Analyt Technol Biomed Life Sci 2017; 1040:250-259. [DOI: 10.1016/j.jchromb.2016.11.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 10/24/2016] [Accepted: 11/05/2016] [Indexed: 12/18/2022]
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Wong ASY, Leung GNW, Leung DKK, Wan TSM. Doping control analysis of anabolic steroids in equine urine by gas chromatography-tandem mass spectrometry. Drug Test Anal 2016; 9:1320-1327. [DOI: 10.1002/dta.2090] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/05/2016] [Accepted: 09/07/2016] [Indexed: 12/20/2022]
Affiliation(s)
- April S. Y. Wong
- Racing Laboratory; The Hong Kong Jockey Club, Sha Tin Racecourse; Hong Kong China
| | - Gary N. W. Leung
- Racing Laboratory; The Hong Kong Jockey Club, Sha Tin Racecourse; Hong Kong China
| | - David K. K. Leung
- Racing Laboratory; The Hong Kong Jockey Club, Sha Tin Racecourse; Hong Kong China
| | - Terence S. M. Wan
- Racing Laboratory; The Hong Kong Jockey Club, Sha Tin Racecourse; Hong Kong China
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9
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Thevis M, Geyer H, Tretzel L, Schänzer W. Sports drug testing using complementary matrices: Advantages and limitations. J Pharm Biomed Anal 2016; 130:220-230. [DOI: 10.1016/j.jpba.2016.03.055] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 03/27/2016] [Indexed: 01/14/2023]
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11
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Kunze M, Wirthgen E, Walz C, Spitschak M, Brenmoehl J, Vanselow J, Schwerin M, Wimmers K, Hoeflich A. Bioanalytical validation for simultaneous quantification of non-aromatic steroids in follicular fluid from cattle via ESI-LC-MS/MS. J Chromatogr B Analyt Technol Biomed Life Sci 2015; 1007:132-9. [PMID: 26600283 DOI: 10.1016/j.jchromb.2015.10.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 10/02/2015] [Accepted: 10/11/2015] [Indexed: 12/07/2022]
Abstract
The family of steroid hormones is quite attractive for the approach of phenotype monitoring in farm animals. Therefore, we developed a new protocol for the quantitative analysis of natural steroids in follicular fluid from dairy cows. The corresponding steroid profile, which consists of progesterone, corticosterone, hydrocortisone, testosterone, and androstenedione covering three distinct steroid classes, was determined by LC/MS. Quantification is achieved by use of steroid standards diluted in steroid-free follicular fluid as calibrators. Thus, the new protocol does not require deuterated standards. In order to correct for conditional performance of the analytical system we have used dexamethasone as an internal standard. The method was validated according to EMA guidelines. Within- and between-day variations were below 20% for most parameters assessed. All steroids assessed had lower limits of quantification in the range of 2.1 to 4.4ng/ml. We have established a simple and sensitive analytical system in order to step towards a broader and cost-efficient phenotyping analysis in follicular fluid from dairy cows.
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Affiliation(s)
- Martin Kunze
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology, W.-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Elisa Wirthgen
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology, W.-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Christina Walz
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology, W.-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Marion Spitschak
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology, W.-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Julia Brenmoehl
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology, W.-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Jens Vanselow
- Institute of Reproductive Biology, Leibniz Institute for Farm Animal Biology, W.-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Manfred Schwerin
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology, W.-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Klaus Wimmers
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology, W.-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Andreas Hoeflich
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology, W.-Stahl-Allee 2, 18196 Dummerstorf, Germany.
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12
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Derivatization of steroids in biological samples for GC–MS and LC–MS analyses. Bioanalysis 2015; 7:2515-36. [DOI: 10.4155/bio.15.176] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The determination of steroids in biological samples is essential in different areas of knowledge. MS combined with either GC or LC is considered the best analytical technique for specific and sensitive determinations. However, due to the physicochemical properties of some steroids, and the low concentrations found in biological samples, the formation of a derivative prior to their analysis is required. In GC–MS determinations, derivatization is needed for generating volatile and thermally stable compounds. The improvement in terms of stability and chromatographic retention are the main reasons for selecting the derivatization agent. On the other hand, derivatization is not compulsory in LC–MS analyses and the derivatization is typically used for improving the ionization and therefore the overall sensitivity achieved.
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13
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Kwok WH, Kwok KY, Leung DKK, Leung GNW, Wong CHF, Wong JKY, Wan TSM. In vitro metabolism studies of desoxy-methyltestosterone (DMT) and its five analogues, and in vivo metabolism of desoxy-vinyltestosterone (DVT) in horses. JOURNAL OF MASS SPECTROMETRY : JMS 2015; 50:994-1005. [PMID: 28338272 DOI: 10.1002/jms.3613] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 04/13/2015] [Accepted: 05/04/2015] [Indexed: 06/06/2023]
Abstract
The positive findings of norbolethone in 2002 and tetrahydrogestrinone in 2003 in human athlete samples confirmed that designer steroids were indeed being abused in human sports. In 2005, an addition to the family of designer steroids called 'Madol' [also known as desoxy-methyltestosterone (DMT)] was seized by government officials at the US-Canadian border. Two years later, a positive finding of DMT was reported in a mixed martial arts athlete's sample. It is not uncommon that doping agents used in human sports would likewise be abused in equine sports. Designer steroids would, therefore, pose a similar threat to the horseracing and equestrian communities. This paper describes the in vitro metabolism studies of DMT and five of its structural analogues with different substituents at the 17α position (RH, ethyl, vinyl, ethynyl and 2 H3 -methyl). In addition, the in vivo metabolism of desoxy-vinyltestosterone (DVT) in horses will be presented. The in vitro studies revealed that the metabolic pathways of DMT and its analogues occurred predominantly in the A-ring by way of a combination of enone formation, hydroxylation and reduction. Additional biotransformation involving hydroxylation of the 17α-alkyl group was also observed for DMT and some of its analogues. The oral administration experiment revealed that DVT was extensively metabolised and the parent drug was not detected in urine. Two in vivo metabolites, derived respectively from (1) hydroxylation of the A-ring and (2) di-hydroxylation together with A-ring double-bond reduction, could be detected in urine up to a maximum of 46 h after administration. Another in vivo metabolite, derived from hydroxylation of the A-ring with additional double-bond reduction and di-hydroxylation of the 17α-vinyl group, could be detected in urine up to a maximum of 70 h post-administration. All in vivo metabolites were excreted mainly as glucuronides and were also detected in the in vitro studies. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Wai Him Kwok
- Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, NT, Hong Kong, China
| | - Karen Y Kwok
- Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, NT, Hong Kong, China
| | - David K K Leung
- Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, NT, Hong Kong, China
| | - Gary N W Leung
- Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, NT, Hong Kong, China
| | - Colton H F Wong
- Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, NT, Hong Kong, China
| | - Jenny K Y Wong
- Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, NT, Hong Kong, China
| | - Terence S M Wan
- Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, NT, Hong Kong, China
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Cawley AT, Blakey K, Waller CC, McLeod MD, Boyd S, Heather A, McGrath KC, Handelsman DJ, Willis AC. Detection and metabolic investigations of a novel designer steroid: 3-chloro-17α-methyl-5α-androstan-17β-ol. Drug Test Anal 2015; 8:621-32. [DOI: 10.1002/dta.1832] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Revised: 05/11/2015] [Accepted: 05/28/2015] [Indexed: 01/30/2023]
Affiliation(s)
- Adam T. Cawley
- Australian Racing Forensic Laboratory; Racing NSW; Randwick NSW Australia
| | - Karen Blakey
- Forensic and Scientific Services, Health Support Queensland; Department of Health, Queensland Government; Archerfield QLD Australia
| | - Christopher C. Waller
- Research School of Chemistry; Australian National University; Canberra ACT Australia
| | - Malcolm D. McLeod
- Research School of Chemistry; Australian National University; Canberra ACT Australia
| | - Sue Boyd
- Magnetic Resonance Facility, School of Natural Sciences; Griffith University; Nathan QLD Australia
| | - Alison Heather
- Faculty of Science; University of Technology; Sydney NSW Australia
- Currently with the Department of Physiology; University of Otago; Dunedin New Zealand
| | | | | | - Anthony C. Willis
- Research School of Chemistry; Australian National University; Canberra ACT Australia
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Thevis M, Kuuranne T, Geyer H, Schänzer W. Annual banned-substance review: analytical approaches in human sports drug testing. Drug Test Anal 2014; 7:1-20. [DOI: 10.1002/dta.1769] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2014] [Accepted: 12/01/2014] [Indexed: 12/13/2022]
Affiliation(s)
- Mario Thevis
- Center for Preventive Doping Research - Institute of Biochemistry; German Sport University Cologne; Am Sportpark Müngersdorf 6 50933 Cologne Germany
- European Monitoring Center for Emerging Doping Agents; Cologne Germany
| | - Tiia Kuuranne
- Doping Control Laboratory; United Medix Laboratories; Höyläämötie 14 00380 Helsinki Finland
| | - Hans Geyer
- Center for Preventive Doping Research - Institute of Biochemistry; German Sport University Cologne; Am Sportpark Müngersdorf 6 50933 Cologne Germany
| | - Wilhelm Schänzer
- Center for Preventive Doping Research - Institute of Biochemistry; German Sport University Cologne; Am Sportpark Müngersdorf 6 50933 Cologne Germany
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