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13C/12C ratios of endogenous urinary steroids investigated for doping control purposes. / Piper, Thomas; Flenker, Ulrich; Mareck, Ute; Schänzer, Wilhelm.
in: Drug testing and analysis, Jahrgang 1, Nr. 2, 01.02.2009, S. 65-72.Publikationen: Beitrag in Fachzeitschrift › Zeitschriftenaufsätze › Forschung
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TY - JOUR
T1 - 13C/12C ratios of endogenous urinary steroids investigated for doping control purposes
AU - Piper, Thomas
AU - Flenker, Ulrich
AU - Mareck, Ute
AU - Schänzer, Wilhelm
N1 - Copyright 2009 John Wiley & Sons, Ltd. Copyright 2009 John Wiley & Sons, Ltd.
PY - 2009/2/1
Y1 - 2009/2/1
N2 - In order to detect the misuse of endogenous anabolic steroids such as testosterone by athletes a total of n = 1734 suspicious urine samples were investigated by gas chromatography/combustion/isotope ratio mass spectrometry throughout the years 2005, 2006 and 2007. The (13)C/(12)C ratio of a target substance (androsterone, a testosterone metabolite) was compared to the (13)C/(12)C ratio of an endogenous reference compound (11beta-hydroxyandrosterone).N = 1340 samples were investigated due to elevated testosterone/epitestosterone ratios, with n = 87 (6.5%) exceptional findings regarding their isotopic ratios. An additional n = 164 samples were investigated because of elevated dehydroepiandrosterone concentrations, with n = 2 (1.2%) exceptional findings. The remainder were subjected to isotope ratio analysis because of elevated androsterone levels or because this was requested by sports federations.Significant differences between female and male samples were found for the (13)C/(12)C ratios of androsterone and 11beta-hydroxyandrosterone but not for samples taken in or out of competition.A further n = 645 samples originating from other World Anti-Doping Agency accredited laboratories, mainly throughout Europe as well as South America, South Africa and Southeast Asia, were investigated. The (13)C/(12)C ratios of the urinary steroids differ significantly for each geographical region, reflecting the dietary status of the individuals.The system stability over time has been tested by repeated injections of a standard solution and repeated processing of frozen stored blank urine. Despite a drift over time in absolute (13)C/(12)C ratios, no significant change in the difference of (13)C/(12)C (11beta-hydroxyandrosterone) minus (13)C/(12)C (androsterone) could be observed.
AB - In order to detect the misuse of endogenous anabolic steroids such as testosterone by athletes a total of n = 1734 suspicious urine samples were investigated by gas chromatography/combustion/isotope ratio mass spectrometry throughout the years 2005, 2006 and 2007. The (13)C/(12)C ratio of a target substance (androsterone, a testosterone metabolite) was compared to the (13)C/(12)C ratio of an endogenous reference compound (11beta-hydroxyandrosterone).N = 1340 samples were investigated due to elevated testosterone/epitestosterone ratios, with n = 87 (6.5%) exceptional findings regarding their isotopic ratios. An additional n = 164 samples were investigated because of elevated dehydroepiandrosterone concentrations, with n = 2 (1.2%) exceptional findings. The remainder were subjected to isotope ratio analysis because of elevated androsterone levels or because this was requested by sports federations.Significant differences between female and male samples were found for the (13)C/(12)C ratios of androsterone and 11beta-hydroxyandrosterone but not for samples taken in or out of competition.A further n = 645 samples originating from other World Anti-Doping Agency accredited laboratories, mainly throughout Europe as well as South America, South Africa and Southeast Asia, were investigated. The (13)C/(12)C ratios of the urinary steroids differ significantly for each geographical region, reflecting the dietary status of the individuals.The system stability over time has been tested by repeated injections of a standard solution and repeated processing of frozen stored blank urine. Despite a drift over time in absolute (13)C/(12)C ratios, no significant change in the difference of (13)C/(12)C (11beta-hydroxyandrosterone) minus (13)C/(12)C (androsterone) could be observed.
KW - Anabolic Agents
KW - Androsterone
KW - Carbon
KW - Carbon Isotopes
KW - Dehydroepiandrosterone
KW - Doping in Sports
KW - Epitestosterone
KW - Female
KW - Humans
KW - Male
KW - Mass Spectrometry
KW - Substance Abuse Detection
KW - Testosterone
U2 - 10.1002/dta.15
DO - 10.1002/dta.15
M3 - Journal articles
VL - 1
SP - 65
EP - 72
JO - Drug testing and analysis
JF - Drug testing and analysis
SN - 1942-7603
IS - 2
ER -
ID: 136341