Author Andrew Phillips discusses the successful application of Gas Chromatography Combustion Isotope Ratio Mass Spectrometry (GC-C-IRMS), as opposed to conventional testing methods, in proving testosterone administration in this literature, Gas Chromatography Combustion Isotope Ratio Mass Spectrometry for Confirming Testosterone Administration from Urinary Androstanediols (AN501/LA Version 1). It relies on the natural differences in d13C content of synthetic testosterone and endogenous hormone.
Gas chromatography mass spectrometry is used to determine the excreted testosterone/epitestosterone (T/E) ratio from the urine, despite studies showing it has a high rate of false negative results. Historically, a T/E ratio of >6:1 is accepted because the world population T/E ratio generally falls below it. The study, incorporating this company’s IsoPrime isotope ratio mass spectrometer, shows the capability of GC-C-IRMS as a detection method for testosterone abuse in athletes. Micromass