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1.
Drug Test Anal ; 15(8): 853-864, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37055939

RESUMO

The frequent detection of anabolic androgenic steroids (AAS) indicates their popularity among rule-breaking athletes. The so called long-term metabolites play a crucial role in their detection, and non-hydrolysed sulphated metabolites have gained renewed interest, as research has demonstrated their extended detection time compared to the more conventional markers (e.g., for metenolone and mesterolone). Their potential has been investigated using liquid and gas chromatography-mass spectrometry (LC- and GC-MS). However, due to their complementary nature, chances are that the most promising metabolite on one technique does not necessarily exhibit the same behaviour on the other and vice versa. Therefore, a comparison was carried out where as a trial model, metenolone, mesterolone and 17α-methyltestosterone were selected and the most likely long-term sulphated metabolites identified on four mass spectrometric instruments. Additionally, using a modified sample preparation procedure, comparison between conventional and non-hydrolysed sulphated metabolites between different GC-MS instruments was also included. When focusing on each individual marker, no cases were observed where a single metabolite provided a superior detection time on all instruments. Furthermore, for each AAS, there were incidences where a metabolite provided the best detection time on one instrument but could only be detected for a shorter period or not at all on other instruments. This demonstrates that metabolite detection windows and hence their added-value as target substance are unique and dependent on the analytical technique and not only on their pharmacokinetic behaviour. Consequently, in each case, a metabolite versus instrument evaluation is needed to maximise the probabilities of detecting doping offences.


Assuntos
Anabolizantes , Doping nos Esportes , Humanos , Anabolizantes/metabolismo , Esteróides Androgênicos Anabolizantes , Cromatografia Gasosa-Espectrometria de Massas/métodos , Mesterolona/metabolismo , Metenolona , Metiltestosterona/química , Metiltestosterona/metabolismo , Detecção do Abuso de Substâncias/métodos , Sulfatos , Espectrometria de Massas em Tandem/métodos
2.
Drug Test Anal ; 15(11-12): 1344-1355, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36843396

RESUMO

Sulfated metabolites have shown to have potential as long-term markers (LTMs) of anabolic-androgenic steroid (AAS) abuse. The compatibility of gas chromatography-mass spectrometry (GC-MS) with trimethylsilyl (TMS)-derivatives of non-hydrolysed sulfated steroids has been demonstrated, where, after derivatisation, generally, two closely eluting isomers are formed that both have the same molecular ion [M-H2 SO4 ]•+ . Sulfated reference standards are in limited commercial availability, and therefore, the current knowledge of the GC-MS behaviour of these compounds is mainly based on sulfating and analysing the available standard reference material. This procedure can unfortunately not cover all of the current known LTMs as these are often not available as pure substance. Therefore, in theory, some metabolites could be missed as they exhibit alternative behaviour. To investigate the matter, in-house sulfated reference materials that bear resemblance to known sulfated LTMs were analysed on GC-MS in their TMS-derivatised non-hydrolysed state. The (alternative) gas chromatographic and mass spectrometric behaviour was mapped, evaluated and linked to the corresponding steroid structures. Afterwards, using fraction collection, known sulfated LTMs were isolated from excretion urine to confirm the observed findings. The categories that were selected were mono-hydroxy-diones, 17-methyl-3,17-diols and 17-keto-3,16-diols as these are commonly encountered AAS conformations. The ability to predict the GC-MS behaviour of non-hydrolysed sulfated AAS metabolites is the corner stone of finding new metabolites. This knowledge is also essential, for example, for understanding AAS detection analyses, for the mass spectrometric characterization of metabolites of new designer steroids or when one needs to characterize an unknown steroid structure.


Assuntos
Anabolizantes , Doping nos Esportes , Esteróides Androgênicos Anabolizantes , Anabolizantes/análise , Sulfatos/metabolismo , Congêneres da Testosterona , Esteroides/análise , Detecção do Abuso de Substâncias/métodos
3.
J Chromatogr A ; 1642: 462039, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33735641

RESUMO

The World Anti-Doping Agency (WADA) publishes yearly their prohibited list, and sets a minimum required performance limit for each substance. To comply with these stringent requirements, the anti-doping laboratories have at least two complementary methods for their initial testing procedure (ITP), one using gas chromatography - mass spectrometry (GC-MS) and the other using liquid chromatography-MS (LC-MS). Anabolic androgenic steroids (AAS) have in previous years consistently been listed as the most frequently detected class of compounds. Over the last decade, evidence has emerged where a longer detection time is attained by focusing on sulfated metabolites of AAS instead of the conventional gluco-conjugated metabolites. Despite a decade of research on sulphated AAS using LC-MS, no LC-MS ITP has been developed that combines this class of compounds with the other mandatory targets. Such combination is essential for economical purposes. Recently, it was demonstrated that the direct injection of non-hydrolysed sulfates is compatible with GC-MS. Using this approach and by taking full use of the open screening capabilities of the quadrupole time of flight MS (QTOF-MS), this work describes for the first time a validated ITP that allows the detection of non-hydrolysed sulfated metabolites of AAS while, simultaneously, remaining capable of detecting a vast range of other classes of compounds, as well as the quantification of endogenous steroids, as required for an ITP compliant with the applicable WADA regulations. The method contains 263 compounds from 9 categories, including stimulants, narcotics, anabolic androgenic steroids and beta-blockers. Additionally, the advantages of the new method were illustrated by analysing excretion samples of drostanolone, mesterolone and metenolone. No negative effects were observed for the conventional markers and the detection time for mesterolone and metenolone increased by up to 150% and 144%, respectively compared to conventional markers.


Assuntos
Anabolizantes/análise , Doping nos Esportes , Cromatografia Gasosa-Espectrometria de Massas/métodos , Programas de Rastreamento , Metaboloma , Esteroides/análise , Adulto , Androstanóis/análise , Humanos , Hidrólise , Limite de Detecção , Masculino , Metenolona/análise , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias/métodos
4.
Drug Test Anal ; 12(8): 1041-1053, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32386339

RESUMO

Sulfated metabolites have been shown to have potential as long-term markers of anabolic-androgenic steroid (AAS) abuse. In 2019, the compatibility of gas chromatography-mass spectrometry (GC-MS) with non-hydrolysed sulfated steroids was demonstrated, and this approach allowed the incorporation of these compounds in a broad GC-MS initial testing procedure at a later stage. However, research is needed to identify which are beneficial. In this study, a search for new long-term metabolites of two popular AAS, metenolone and drostanolone, was undertaken through two excretion studies each. The excretion samples were analysed using GC-chemical ionization-triple quadrupole MS (GC-CI-MS/MS) after the application of three separate sample preparation methodologies (i.e. hydrolysis with Escherichia coli-derived ß-glucuronidase, Helix pomatia-derived ß-glucuronidase/arylsulfatase and non-hydrolysed sulfated steroids). For metenolone, a non-hydrolysed sulfated metabolite, 1ß-methyl-5α-androstan-17-one-3ζ-sulfate, was documented for the first time to provide the longest detection time of up to 17 days. This metabolite increased the detection time by nearly a factor of 2 in comparison with the currently monitored markers for metenolone in a routine doping control initial testing procedure. In the second excretion study, it prolonged the detection window by 25%. In the case of drostanolone, the non-hydrolysed sulfated metabolite with the longest detection time was the sulfated analogue of the main drostanolone metabolite (3α-hydroxy-2α-methyl-5α-androstan-17-one) with a detection time of up to 24 days. However, the currently monitored main drostanolone metabolite in routine doping control, after hydrolysis of the glucuronide with E.coli, remained superior in detection time (i.e. up to 29 days).


Assuntos
Anabolizantes/urina , Androstanóis/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metenolona/urina , Adulto , Anabolizantes/metabolismo , Androstanóis/metabolismo , Doping nos Esportes/prevenção & controle , Humanos , Masculino , Metenolona/metabolismo , Detecção do Abuso de Substâncias/métodos , Sulfatos/urina , Espectrometria de Massas em Tandem/métodos
5.
Drug Test Anal ; 11(11-12): 1656-1665, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31009554

RESUMO

Steroid detection and identification remain key issues in toxicology, drug testing, medical diagnostics, food safety control, and doping control. In this study, we evaluate the capabilities and usefulness of analyzing non-hydrolyzed sulfated steroids with gas chromatography-mass spectrometry (GC-MS) instead of the conventionally applied liquid chromatography-mass spectrometry (LC-MS) approach. Sulfates of 31 steroids were synthesized and their MS and chromatographic behavior studied by chemical ionization-GC-triple quadrupole MS (CI-GC-TQMS) and low energy-electron ionization-GC-quadrupole time-of-flight-MS (LE-EI-GC-QTOF-MS). The collected data shows that the sulfate group is cleaved off in the injection port of the GC-MS, forming two isomers. In CI, the dominant species (ie, [MH - H2 SO4 ]+ or [MH - H4 S2 O8 ]+ for bis-sulfates) is very abundant due to the limited amount of fragmentation, making it an ideal precursor ion for MS/MS. In LE-EI, [M - H2 SO4 ].+ and/or [M - H2 SO4 - CH3 ].+ are the dominant species in most cases. Based on the common GC-MS behavior of non-hydrolyzed sulfated steroids, two applications were evaluated and compared with the conventionally applied LC-MS approach; (a) discovery of (new) sulfated steroid metabolites of mesterolone and (b) expanding anabolic androgenic steroid abuse detection windows. GC-MS and LC-MS analysis of non-hydrolyzed sulfated steroids offered comparable sensitivities, superseding these of GC-MS after hydrolysis. For non-hydrolyzed sulfated steroids, GC-MS offers a higher structural elucidating power and a more straightforward inclusion in screening methods than LC-MS.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Esteroides/metabolismo , Sulfatos/metabolismo , Adulto , Anabolizantes/metabolismo , Anabolizantes/urina , Humanos , Hidrólise , Masculino , Mesterolona/metabolismo , Mesterolona/urina , Pessoa de Meia-Idade , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Sulfatos/urina , Espectrometria de Massas em Tandem/métodos
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