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1.
Anal Chem ; 91(18): 11747-11756, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31423767

RESUMO

Carbon isotope ratio (CIR) confirmation is one of the most complex and delicate analyses in the doping control field, due to the nature of the molecules to be confirmed, normally present in urinary samples as a consequence of an endogenous production. The requirements for method validation established by the World Anti-Doping Agency (WADA) have been pushing the accredited laboratories to improve their methods. The choice of the method is always a cost benefit ratio involving a hard-working and time-consuming analysis and the guarantee of reporting of reliable results. This work presents the method fully validated by the Brazilian Doping Control Laboratory as part of the preparation for the Rio de Janeiro Summer Olympic and Paralympic Games 2016. Sample preparation encompassed solid-phase extraction, liquid-liquid extraction, enzymatic hydrolysis, acetylation, and purification by preparative high-performance liquid chromatography, and analyses were performed by gas chromatography/combustion/isotope ratio mass spectrometry. This proved to be a robust method to CIR confirmation in a big event, as demonstrated by the analysis of 179 samples during the Games 2016, from clearly negative results and adverse findings for testosterone (T) and related substances, boldenone and its metabolite, 19-norandrosterone and formestane. Two atypical findings were also reported for T and metabolites.


Assuntos
Isótopos de Carbono/urina , Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Congêneres da Testosterona/urina , Acetilação , Brasil , Cromatografia Líquida de Alta Pressão , Estranos/urina , Humanos , Extração Líquido-Líquido , Reprodutibilidade dos Testes , Extração em Fase Sólida , Esportes , Testosterona/análogos & derivados , Testosterona/urina
2.
Drug Test Anal ; 9(11-12): 1658-1672, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29078043

RESUMO

This paper summarises the results obtained from the doping control analyses performed during the Summer XXXI Olympic Games (August 3-21, 2016) and the XV Paralympic Games (September 7-18, 2016). The analyses of all doping control samples were performed at the Brazilian Doping Control Laboratory (LBCD), a World Anti-Doping Agency (WADA)-accredited laboratory located in Rio de Janeiro, Brazil. A new facility at Rio de Janeiro Federal University (UFRJ) was built and fully operated by over 700 professionals, including Brazilian and international scientists, administrative staff, and volunteers. For the Olympic Games, 4913 samples were analysed. In 29 specimens, the presence of a prohibited substance was confirmed, resulting in adverse analytical findings (AAFs). For the Paralympic Games, 1687 samples were analysed, 12 of which were reported as AAFs. For both events, 82.8% of the samples were urine, and 17.2% were blood samples. In total, more than 31 000 analytical procedures were conducted. New WADA technical documents were fully implemented; consequently, state-of-the-art analytical toxicology instrumentation and strategies were applied during the Games, including different types of mass spectrometry (MS) analysers, peptide, and protein detection strategies, endogenous steroid profile measurements, and blood analysis. This enormous investment yielded one of the largest Olympic legacies in Brazil and South America. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Dopagem Esportivo , Detecção do Abuso de Substâncias/métodos , Brasil , Humanos , Espectrometria de Massas , América do Sul
3.
Drug Test Anal ; 8(11-12): 1204-1211, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27739243

RESUMO

Measuring carbon isotope ratios (CIRs) of urinary analytes represents a cornerstone of doping control analysis and has been particularly optimized for the detection of the misuse of endogenous steroids. Isotope ratio mass spectrometry (IRMS) of appropriate quality, however, necessitates adequate purities of the investigated steroids, which requires extensive pre-analytical sample clean-up steps due to both the natural presence of the target analytes and the high complexity of the matrix. In order to accelerate the sample preparation and increase the automation of the process, the use of multidimensional gas chromatography (MDGC) prior to IRMS experiments, was investigated. A well-established instrumental configuration based on two independent GC ovens and one heart-cutting device was optimized. The first dimension (1D) separation was obtained by a non-polar column which assured high efficiency and good loading capacity, while the second dimension (2D), based on a mid-polar stationary phase, provided good selectivity. A flame ionization detector monitored the 1D, and the 2D was simultaneously recorded by isotope ratio and quadrupole mass spectrometry. The assembled MDGC set-up was applied for measuring testosterone, 5α- and 5ß-androstanediol, androsterone, and etiocholanolone as target compounds and pregnanediol as endogenous reference compound. The urine sample were pretreated by conventional sample preparation steps comprising solid-phase extraction, hydrolysis, and liquid-liquid extraction. The extract obtained was acetylated and different aliquots were injected into the MDGC system. Two high performance liquid chromatography steps, conventionally adopted prior to CIR measurements, were replaced by the MDGC approach. The obtained values were consistent with the conventional ones. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Anabolizantes/urina , Androsterona/urina , Isótopos de Carbono/urina , Cromatografia Líquida de Alta Pressão/métodos , Etiocolanolona/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Esteroides/análise , Testosterona/urina , Anabolizantes/química , Androsterona/análise , Androsterona/química , Cromatografia Gasosa , Dopagem Esportivo , Etiocolanolona/análise , Etiocolanolona/química , Humanos , Espectrometria de Massas , Esteroides/química , Esteroides/metabolismo , Testosterona/análise
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