Titre
Correction of the urinary testosterone to epitestosterone ratio measurement in antidoping analyses by chromatographic and mass spectrometric techniques.
Type
article
Institution
UNIL/CHUV/Unisanté + institutions partenaires
Périodique
Auteur(s)
Martínez Brito, D.
Auteure/Auteur
Vidal, T.C.
Auteure/Auteur
de la Torre, X.
Auteure/Auteur
de Oca Porto, R.M.
Auteure/Auteur
Botrè, F.
Auteure/Auteur
Liens vers les personnes
Liens vers les unités
ISSN
1942-7611
Statut éditorial
Publié
Date de publication
2023
Volume
15
Numéro
11-12
Première page
1382
Dernière page/numéro d’article
1391
Peer-reviewed
Oui
Langue
anglais
Notes
Publication types: Journal Article
Publication Status: ppublish
Publication Status: ppublish
Résumé
The ratio of testosterone (T) to epitestosterone (E) determined in urine samples is the main biomarker used to prove T and precursors abused by athletes. Analytically, the correction of the ratio is required by the World Anti-Doping Agency. This work describes a series of experiments aimed to study when it is appropriate to correct the T/E ratio value, using different mass spectrometric techniques since only reports on GC-MS exist. Analyses using external calibrators, controls, and routine samples were performed by three different techniques GC-MS, GC-MS <sup>n</sup> , and LC-MS <sup>n</sup> . A statistical comparison of the T/E was performed after the application of two corrections previously published: Isotopic contribution peak area correction (corr_1) and use of a verified internal deuterated internal standard (TD3/ED3) correction (corr_2) and the ratio based on T and E concentrations. The use of external calibration samples introduces biases that influence not only the T and E concentrations but also the T/E ratio, even when both methods of correction are applied. The correction after applying corr_1 method barely contributed to the accuracy of the T/E calculation. Nevertheless, the application of the corr_2 method increased the accuracy between 5% and 6% when comparing theoretical and experimental T/E values. Finally, the best results were obtained by the ratio calculated directly from the estimated concentrations of T and E. Attention must be paid when the T/E is measured by LC-MS <sup>n</sup> since different acquisition modes produced significantly different results, even in MS/MS when the same transition is used for T and E.
PID Serval
serval:BIB_EC793DF41CED
PMID
Open Access
Oui
Date de création
2023-03-13T15:46:05.663Z
Date de création dans IRIS
2025-05-21T05:26:48Z