Investigations on the in vivo metabolism of 5α-androst-2-en-17-one

Annual banned-substance review-Analytical approaches in human sports drug testing 2021/2022

Also in 2021/2022, considerable efforts were invested into advancing human sports drug testing programs, recognizing and taking into account existing as well as emerging challenges in anti-doping, especially with regard to substances and methods of doping specified in the World Anti-Doping Agency's 2022 Prohibited List. In this edition of the annual banned-substance review, literature on recent developments published between October 2021 and September 2022 is summarized and discussed. Focus is put particularly on enhanced analytical approaches and complementary testing options in human doping controls, appreciating the exigence and mission in anti-doping and, equally, the contemporary "new normal" considering, for example, the athlete's exposome versus analytical sensitivity and applicable anti-doping regulations for result interpretation and management.

Addressing recent challenges in isotope ratio mass spectrometry: Development of a method applicable to 1-androstene-steroids, 6α-hydroxy-androstenedione and androstatrienedione

In 2020, the confirmation of the non-endogenous origin of several pseudo-endogenous steroids by means of isotope ratio mass spectrometry (IRMS) was recommended by the World Anti-Doping Agency (WADA), in addition to previously established target analytes for IRMS in sports drug testing. To date, however, IRMS-based methods validated in accordance with current WADA regulations have not been available. Therefore, the aim of this research project was the development and validation of a method to determine the carbon isotope ratios (CIR) of all newly considered pseudo-endogenous steroids, encompassing the anabolic androgenic steroids comprising a 1-ene-core structure (5α-androst-1-ene-3β,17β-diol, 5α-androst-1-ene-3,17-dione (1AD), 17β-hydroxy-5α-androst-1-en-3-one, 3α-hydroxy-5α-androst-1-ene-17-one (1AND), and 3β-hydroxy-5α-androst-1-ene-17-one (1EpiAND)), as well as steroids referred to as hormone and metabolic modulators (androsta-1,4,6-triene-3,17-dione (TRD) and its main metabolite 17β-hydroxy-androsta-1,4,6-triene-3-one) and 6α- and 6β-hydroxy-androst-4-ene-3,17-dione. With peak purity of target analytes being critical for IRMS analyses, a twofold high-performance liquid chromatography (HPLC)-based sample purification was employed, with all analytes being acetylated between the first and second HPLC fractionation. Using established gas chromatography/combustion/IRMS (GC/C/IRMS) instrumentation, limits of quantification were estimated at 10 ng/mL for a 20 mL urine aliquot for all analytes, except for 1AND (20 ng/mL), and combined measurement uncertainties were estimated between 0.4 and 0.9 ‰. For proof-of-concept, samples collected after the single oral administration of a nutritional supplement containing 1AD and 1EpiAND were analyzed as well as existing excretion study urine samples obtained after the administration of 4-androstenedione and TRD. Based on the obtained results, the developed method was considered to be fit-for-purpose.