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1.
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
2.
Drug Test Anal ; 7(11-12): 1030-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26472592

RESUMO

Improvements in doping analysis can be effected by speeding up analysis time and extending the detection time. Therefore, direct detection of phase II conjugates of doping agents, especially anabolic androgenic steroids (AAS), is proposed. Besides direct detection of conjugates with glucuronic acid, the analysis of sulfate conjugates, which are usually not part of the routine doping control analysis, can be of high interest. Sulfate conjugates of methandienone and methyltestosterone metabolites have already been identified as long-term metabolites. This study presents the synthesis of sulfate conjugates of six commonly used AAS and their metabolites: trenbolone, nandrolone, boldenone, methenolone, mesterolone, and drostanolone. In the following these sulfate conjugates were used for development of a fast and easy analysis method based on sample preparation using solid phase extraction with a mixed-mode sorbent and detection by high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). Validation demonstrated the suitability of the method with regard to the criteria given by the technical documents of the World Anti-Doping Agency (WADA). In addition, suitability has been proven by successful detection of the synthesized sulfate conjugates in excretion urines and routine doping control samples.


Assuntos
Anabolizantes/urina , Cromatografia Líquida de Alta Pressão , Dopagem Esportivo , Mesterolona/urina , Substâncias para Melhoria do Desempenho/urina , Espectrometria de Massas por Ionização por Electrospray , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Sulfatos/urina , Espectrometria de Massas em Tandem , Adulto , Calibragem , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Desintoxicação Metabólica Fase II , Valor Preditivo dos Testes , Padrões de Referência , Eliminação Renal , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/normas , Detecção do Abuso de Substâncias/normas , Espectrometria de Massas em Tandem/normas , Urinálise
3.
J Mass Spectrom ; 50(1): 153-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25601687

RESUMO

In this paper, mesterolone metabolic profiles were investigated carefully. Mesterolone was administered to one healthy male volunteer. Urinary extracts were analyzed by liquid chromatography quadruple time-of-flight mass spectrometry (LC-QTOFMS) for the first time. Liquid-liquid extraction was applied to processing urine samples, and dilute-shoot analyses of intact metabolites were also presented. In LC-QTOFMS analysis, chromatographic peaks for potential metabolites were hunt down by using the theoretical [M-H](-) as target ions in full scan experiment, and their actual deprotonated ions were analyzed in targeted MS/MS mode. Ten metabolites including seven new sulfate and three glucuronide conjugates were found for mesterolone. Because of no useful fragment ion for structural elucidation, gas chromatography-mass spectrometry instrumentation was employed to obtain structural details of the trimethylsilylated phase I metabolite released after solvolysis. Thus, their potential structures were proposed particularly by a combined MS approach. All the metabolites were also evaluated in terms of how long they could be detected, and S1 (1α-methyl-5α-androst-3-one-17ß-sulfate) together with S2 (1α-methyl-5α-androst-17-one-3ß-sulfate) was detected up to 9 days after oral administration, which could be the new potential biomarkers for mesterolone misuse.


Assuntos
Biomarcadores/urina , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Mesterolona/metabolismo , Mesterolona/urina , Administração Oral , Adulto , Anabolizantes/urina , Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas , Glucuronídeos/química , Glucuronídeos/metabolismo , Glucuronídeos/urina , Humanos , Extração Líquido-Líquido , Masculino , Espectrometria de Massas/instrumentação , Mesterolona/administração & dosagem , Mesterolona/análogos & derivados , Espectrometria de Massas em Tandem/métodos
4.
J Steroid Biochem Mol Biol ; 42(3-4): 399-410, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1606051

RESUMO

New metabolites of mesterolone, methenolone and stenbolone bearing a C18 hydroxyl group were isolated from the steroid glucuronide fraction of urine specimens collected after administration of single 50 mg doses of these steroids to human subjects. Mesterolone gave rise to four metabolites which were identified by gas chromatography/mass spectrometry as 18-hydroxy-1 alpha-methyl-5 alpha-androstan-3,17-dione 1, 3 alpha,18-dihydroxy-1 alpha-methyl-5 alpha-androstan-17-one 2, 3 beta,18-dihydroxy-1-alpha-methyl-5 alpha-androstan-17-one 3 and 3 alpha,6 xi,18-trihydroxy-1 alpha-methyl-5 alpha-androstan-17-one 4. These data suggest that mesterolone itself was not hydroxylated at C18, but rather 1 alpha-methyl-5 alpha-androstan-3,17-dione, an intermediate metabolite which results from oxidation of mesterolone 17-hydroxyl group. In addition to hydroxylation at C18, reduction of the 3-keto group and further hydroxylation at C6 were other reactions that led to the formation of these metabolites. It is of interest to note that in the case of both methenolone and stenbolone, only one 18-hydroxylated urinary metabolite namely 18-hydroxy-1-methyl-5 alpha-androst-1-ene-3,17-dione 5 and 18-hydroxy-1-methyl-5 alpha-androst-1-ene-3,17-dione 6 were both detected in post-administration urine specimens. These data indicate that the presence of a methyl group at the C1 or C2 positions in the steroids studied is a structural feature that seems to favor interaction of hepatic 18-hydroxylases with these steroids. These data provide further evidence that 18-hydroxylation of endogenous steroids can also occur in extra-adrenal sites in man.


Assuntos
Androstenóis/metabolismo , Mesterolona/metabolismo , Metenolona/metabolismo , Androstenóis/química , Androstenóis/urina , Cromatografia Gasosa-Espectrometria de Massas , Glucuronatos/química , Ácido Glucurônico , Humanos , Hidroxilação , Mesterolona/química , Mesterolona/urina , Metenolona/química , Metenolona/urina , Esteroide Hidroxilases/metabolismo , Sulfatos/química
5.
J Steroid Biochem Mol Biol ; 42(3-4): 411-9, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1606052

RESUMO

Before including the detection of the methyl-5 alpha-dihydrotestosterones mesterolone (1 alpha-methyl-17 beta-hydroxy-5 alpha-androstan-3-one) and drostanolone (2 alpha-methyl-17 beta-hydroxy-5 alpha-androstan-3-one) in doping control procedures, their urinary metabolites were characterized by gas chromatography/mass spectrometry. Several metabolites were found after enzymatic hydrolysis and conversion of the respective metabolites to their trimethylsilyl-enol-trimethylsilyl ether derivatives. The major metabolites of mesterolone and drostanolone were identified as 1 alpha-methyl-androsterone and 2 alpha-methyl-androsterone, respectively. The parent compounds and the intermediate 3 alpha,17 beta-dihydroxysteroid metabolites were detected as well. The reduction into the corresponding 3 beta-hydroxysteroids was a minor metabolic pathway. All metabolites were found to be conjugated to glucuronic acid.


Assuntos
Androstanóis/metabolismo , Mesterolona/metabolismo , Androstanóis/química , Androstanóis/urina , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidroxilação , Cetosteroides/química , Mesterolona/química , Mesterolona/urina , Oxirredução , Estereoisomerismo , Fatores de Tempo
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