Screening urine for exogenous testosterone by isotope ratio mass spectrometric analysis of one pregnanediol and two androstanediols
We propose a new screening method for testosterone (T) doping in sport. The current method for detecting T administration is based on finding a T to epitestosterone ratio (T/E) in urine that exceeds six. The difficulties with T/E are that T administration does not always result in a T/E>6 and tha...
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Published in | Journal of chromatography. B, Biomedical sciences and applications Vol. 727; no. 1; pp. 95 - 105 |
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Main Authors | , , , , , , , |
Format | Journal Article |
Language | English |
Published |
Amsterdam
Elsevier B.V
30.04.1999
Elsevier Science Elsevier |
Subjects | |
Online Access | Get full text |
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Summary: | We propose a new screening method for testosterone (T) doping in sport. The current method for detecting T administration is based on finding a T to epitestosterone ratio (T/E) in urine that exceeds six. The difficulties with T/E are that T administration does not always result in a T/E>6 and that a rare individual will have T/E>6 in the absence of T administration. Our previous studies reveal that carbon isotope ratio helps to determine the origin of the urinary T because the values for T and its metabolites decrease after the administration of exogenous T. In this study, we present a rapid and efficient screening sample preparation method based on three successive liquid–solid extractions, deconjugation with
E. coli β-glucuronidase after the first extraction, acetylation after the second extraction, and a final extraction of the acetates. The
13C/
12C of two T metabolites (5β-androstane-3α,17β-diol and 5α-androstane-3α,17β-diol) and one pregnanediol as endogenous reference (5β-pregnane-3α,20α-diol) was measured by gas chromatography–combustion–isotope ratio mass spectrometry (GC–C–IRMS) on 10 ml of urine collected from 10 healthy men before and after T administration. Following T administration, the
13C/
12C of 5β-androstane-3α,17β-diol diacetate and 5α-androstane-3α,17β-diol diacetate declined significantly from −26.2‰ to −30.8‰ and from −25.2‰ to −29.9‰, respectively and the
13C/
12C of 5β-pregnane-3α,20α-diol diacetate was unchanged. In addition, the ratio of androstanediols to pregnanediol increased in the post-T urines. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 |
ISSN: | 0378-4347 1387-2273 |
DOI: | 10.1016/S0378-4347(99)00066-3 |