Longitudinal profiling of urinary steroids by gas chromatography/combustion/isotope ratio mass spectrometry: Diet change may result in carbon isotopic variations

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• 作者：Christophe Saudan ; Matthias Kamber ; Giulia Barbati ; Neil Robinson ; Auré ; lien Desmarchelier ; Patrice Mangin and Martial Saugy
• 关键词：Steroids ; Diet ; Isotope ratio mass spectrometry (IRMS) ; Doping control
• 刊名：Journal of Chromatography B, Analytical Technologies in the Biomedical and Life Sciences
• 出版年：2006
• 出版时间：2 February 2006
• 年：2006
• 卷：831
• 期：1-2
• 页码：324-327
• 全文大小：169 K

文摘

Longitudinal profiling of urinary steroids was investigated by using a gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) method. The carbon isotope ratio of three urinary testosterone (T) metabolites: androsterone, etiocholanolone, 5β-androstane-3α,17β-diol (5β-androstanediol) together with 16(5α)-androsten-3α-ol (androstenol) and 5β-pregnane-3α,20α-diol (5β-pregnanediol) were measured in urine samples collected from three top-level athletes over 2 years. Throughout the study, the subjects were living in Switzerland and were residing every year for a month or two in an African country. ¹³C-enrichment larger than 2.5‰ was observed for one subject after a 2-month stay in Africa. Our findings reveal that ¹³C-enrichment caused by a diet change might be reduced if the stay in Africa was shorter or if the urine sample was not collected within the days after return to Switzerland. The steroids of interest in each sample did not show significant isotopic fractionation that could lead to false positive results in anti-doping testing. In contrast to the results obtained with the carbon isotopic ratio, profiling of urinary testosterone/epitestosterone (T/E) ratios was found to be unaffected by a diet change.