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Published on: June 1, 2022
delta13C-values of endogenous urinary steroids
Ulrich Flenker1, Ute Güntner, Wilhelm Schänzer
1Institute of Biochemistry, German Sport University Cologne, Carl-Diem-Weg 6, 50933 Cologne, Germany. uli@biochem.dshs-koeln.de
Steroids
|February 5, 2008
Summary
This study analyzed urinary steroid carbon isotope ratios to detect synthetic androgen doping. Differences in delta(13)C-values between androgen metabolites and endogenous reference compounds can identify illicit use.
Area of Science:
- Biochemistry
- Analytical Chemistry
- Sports Science
Background:
- Detecting synthetic androgen doping is crucial for fair competition.
- Carbon isotope ratio analysis of urinary steroids offers a potential method for doping control.
Purpose of the Study:
- To establish reference ranges for urinary steroid delta(13)C-values.
- To evaluate the utility of endogenous reference compounds (ERCs) for detecting synthetic androgen use.
- To identify factors influencing steroid isotope ratios.
Main Methods:
- Gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) was used to analyze urinary steroids.
- Carbon isotope ratios ((13)C/(12)C) of androsterone, etiocholanolone, and other steroids were measured.
- Delta(13)C-values and their differences (Delta(13)C) were calculated and reference ranges established.
Main Results:
- Delta(13)C-values between androsterone and ERCs exceeding 3 per thousand are highly unlikely in non-doping cases.
- Factors such as steroid identity, sex, oral contraception, travel, and physical activity significantly influence urinary steroid delta(13)C-values.
Conclusions:
- Carbon isotope ratio analysis of urinary steroids, using ERCs, shows promise for detecting synthetic androgen doping.
- Established reference ranges and consideration of influencing factors are essential for accurate interpretation of doping control samples.
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