### Development of a sensitive GC-C-IRMS method for the analysis of androgens in doping control

Michaël Polet UGent, Wim Van Gansbeke UGent and Peter Van Eenoo UGent (2012) p.21-21
abstract
All doping control laboratories accredited by the World Anti-Doping Agency (WADA) have been confronted with the task to develop analytical methods and establish criteria that allow endogenous steroids to be distinguished from their synthetic copies. It has been known for some time that gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) is capable of meeting this challenge by comparison of the 13C/12C ratios of the target compounds with those of endogenous reference compounds that are not affected by the administration of synthetic androgens. Testosterone and/or its main metabolites function as target compounds. Typical endogenous reference compounds include 5β-pregnanediol, 11-ketoetiocholanolone and 11-βhydroxyandrosterone. Synthetic copies are generally derived from stigmasterol and sitosterol; plant sterols obtained from soybean (Glycine max) which have a significantly different carbon isotope composition compared to endogenous steroids. As a consequence, the administration of synthetic analogs is detectable through a change in the carbon isotopic composition of testosterone and its metabolites. GC-C-IRMS however remains a very laborious and expensive technique because one can only determine the 13C/12C ratio of a pure compound. This means that a lot of purification steps have to be conducted and fractionation caused by one of these steps is unacceptable. On top of that, substantial amounts of urine are needed to meet the sensitivity requirements of the IRMS. Because the amount of received urine from an athlete is limited, doping control laboratories have to make their analysis as sensitive as possible so all the required doping tests can be executed. If less urine is consumed, then there is more available for additional tests. In this work we introduce a new type of injection which takes GC-C-IRMS to the next level. With the aid of a programmed temperature vaporizer we were able to increase the sensitivity of the IRMS with a factor of 10 and we drastically reduced the required amount of urine and the limit of detection. All this is achieved without having to change any of the IRMS detection parameters.
author
organization
year
type
conference
publication status
published
subject
keyword
androgens, doping control, solvent vent injection, GC-C-IRMS
in
Benelux Association of Stable Isotope Scientists, Annual meeting, Abstracts
pages
21 - 21
publisher
Cito Arnhem
place of publication
Arnhem, Nederland
conference name
Benelux Association of Stable Isotope Scientists annual meeting 2012 (BASIS 2012)
conference location
Nijmegen, The Netherlands
conference start
2012-04-12
conference end
2012-04-13
language
English
UGent publication?
yes
classification
C3
id
3010271
handle
http://hdl.handle.net/1854/LU-3010271
date created
2012-10-10 08:25:54
date last changed
2012-10-10 14:58:21
@inproceedings{3010271,
abstract     = {All doping control laboratories accredited by the World Anti-Doping Agency (WADA) have been confronted with the task to develop analytical methods and establish criteria that allow endogenous steroids to be distinguished from their synthetic copies. It has been known for some time that gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) is capable of meeting this challenge by comparison of the 13C/12C ratios of the target compounds with those of endogenous reference compounds that are not affected by the administration of synthetic androgens. Testosterone and/or its main metabolites function as target compounds. Typical endogenous reference compounds include 5\ensuremath{\beta}-pregnanediol, 11-ketoetiocholanolone and 11-\ensuremath{\beta}hydroxyandrosterone. Synthetic copies are generally derived from stigmasterol and sitosterol; plant sterols obtained from soybean (Glycine max) which have a significantly different carbon isotope composition compared to endogenous steroids. As a consequence, the administration of synthetic analogs is detectable through a change in the carbon isotopic composition of testosterone and its metabolites.
GC-C-IRMS however remains a very laborious and expensive technique because one can only determine the 13C/12C ratio of a pure compound. This means that a lot of purification steps have to be conducted and fractionation caused by one of these steps is unacceptable. On top of that, substantial amounts of urine are needed to meet the sensitivity requirements of the IRMS. Because the amount of received urine from an athlete is limited, doping control laboratories have to make their analysis as sensitive as possible so all the required doping tests can be executed. If less urine is consumed, then there is more available for additional tests. In this work we introduce a new type of injection which takes GC-C-IRMS to the next level. With the aid of a programmed temperature vaporizer we were able to increase the sensitivity of the IRMS with a factor of 10 and we drastically reduced the required amount of urine and the limit of detection. All this is achieved without having to change any of the IRMS detection parameters.},
author       = {Polet, Micha{\"e}l and Van Gansbeke, Wim and Van Eenoo, Peter},
booktitle    = {Benelux Association of Stable Isotope Scientists, Annual meeting, Abstracts},
keyword      = {androgens,doping control,solvent vent injection,GC-C-IRMS},
language     = {eng},
location     = {Nijmegen, The Netherlands},
pages        = {21--21},
publisher    = {Cito Arnhem},
title        = {Development of a sensitive GC-C-IRMS method for the analysis of androgens in doping control},
year         = {2012},
}


Chicago
Polet, Michaël, Wim Van Gansbeke, and Peter Van Eenoo. 2012. “Development of a Sensitive GC-C-IRMS Method for the Analysis of Androgens in Doping Control.” In Benelux Association of Stable Isotope Scientists, Annual Meeting, Abstracts, 21–21. Arnhem, Nederland: Cito Arnhem.
APA
Polet, M., Van Gansbeke, W., & Van Eenoo, P. (2012). Development of a sensitive GC-C-IRMS method for the analysis of androgens in doping control. Benelux Association of Stable Isotope Scientists, Annual meeting, Abstracts (pp. 21–21). Presented at the Benelux Association of Stable Isotope Scientists annual meeting 2012 (BASIS 2012), Arnhem, Nederland: Cito Arnhem.
Vancouver
1.
Polet M, Van Gansbeke W, Van Eenoo P. Development of a sensitive GC-C-IRMS method for the analysis of androgens in doping control. Benelux Association of Stable Isotope Scientists, Annual meeting, Abstracts. Arnhem, Nederland: Cito Arnhem; 2012. p. 21–21.
MLA
Polet, Michaël, Wim Van Gansbeke, and Peter Van Eenoo. “Development of a Sensitive GC-C-IRMS Method for the Analysis of Androgens in Doping Control.” Benelux Association of Stable Isotope Scientists, Annual Meeting, Abstracts. Arnhem, Nederland: Cito Arnhem, 2012. 21–21. Print.