RESUMEN
Gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) can be used to detect the synthetic forms of endogenous anabolic androgenic steroids (EAAS) by comparing the 13C/12C ratios of the endogenous reference compound to that of the target compound. Isolation and enrichment of the target compound from urinary matrices is an essential prerequisite for the GC/C/IRMS confirmation procedure in doping control analysis. Boldenone (Bo) is a natural anabolic androgenic steroid (AAS) and a derivative of testosterone. The GC/C/IRMS confirmation procedure for Bo and its main metabolite 5ß-androst-1-en-17ß-ol-3-one (BoM) is extremely complicated due to the low concentrations and the enormously complex matrices in urine. The present study demonstrated a sample purification procedure for GC/C/IRMS by using online 2D-HPLC to purify Bo and BoM in urine samples. Bo and BoM with concentrations as low as 2 ng/mL were isolated and enriched with superior purity and selectivity. The validity of the method was verified with the technical document issued by the world anti-doping agency. The online 2D-HPLC purification procedure featured high selectivity for the analytes and no isotopic fractionation in the collection process. The present method can be used as a routine method allowing doping control laboratories to perform Boldenone confirmation.
Asunto(s)
Esteroides Anabólicos Androgénicos , Testosterona , Cromatografía de Gases y Espectrometría de Masas , IsótoposRESUMEN
19-Norandrosterone (19-NA) is the main metabolite of nandrolone and/or its precursors, which can be found naturally in human urine in trace amount. Gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) confirmation procedure can be used to identify a potential exogenous origin of 19-NA in urine sample. Sample purification for GC-C-IRMS analysis is crucial to the whole confirmation procedure because the concentration of 19-NA in the urine to be tested is very low. Online two-dimensional high-performance liquid chromatography (2D-HPLC) clean-up procedure with high separation capacity is used to isolate and enrich 19-NA as a sample pretreatment process. Linearity, lowest detectable concentration, uncertainty, and selectivity of the method are validated according to the World Anti-doping Agency's (WADA) requirement. Isotope fractionation effect was not observed during the 2D-HPLC purification process. The validated method provides a high efficient and convenient confirmation procedure to determine the origin of 19-NA.