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1.
Anal Chim Acta ; 586(1-2): 22-9, 2007 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-17386692

RESUMEN

Since the 1970s, many analytical methods for the detection of illegal growth promoters, such as thyreostats, anabolics, beta-agonists and corticosteroids have been developed for a wide range of matrices of animal origin, including meat, fat, organ tissue, urine and faeces. The aim of this study was to develop an analytical method for the determination of ng L(-1) levels of estrogens, gestagens, androgens (EGAs) and corticosteroids in aqueous preparations (i.e. drinking water, drinking water supplements), commercially available on the 'black' market. For this, extraction was performed with Bakerbond C18 speedisk, a technique commonly used in environmental analysis. After fractionation, four fractions were collected using a methanol:water gradient program. Gas chromatography coupled to electron impact multiple mass spectrometry (GC-EI-MS2) screening for the EGAs was carried out on the derivatized extracts. For the detection of corticosteroids, gas chromatography coupled to negative chemical ionization mass spectrometry (GC-NCI-MS) was used after oxidation of the extracts. Confirmation was done by liquid chromatography coupled to electrospray ionization multiple mass spectrometry (LC-ESI-MS2). The combined use of GC and LC coupled to MS enabled the identification and quantification of anabolics and corticosteroids at the low ng L(-1) level. This study demonstrated the occurrence of both androgens and corticosteroids in different commercial aqueous samples.


Asunto(s)
Corticoesteroides/análisis , Residuos de Medicamentos/análisis , Estrógenos/análisis , Tejido Adiposo/metabolismo , Animales , Cromatografía de Gases/métodos , Heces , Espectrometría de Masas/métodos , Carne , Modelos Químicos , Progestinas/análisis , Espectrometría de Masa por Ionización de Electrospray , Esteroides/análisis , Urinálisis/métodos , Agua/análisis
2.
Anal Chim Acta ; 586(1-2): 57-72, 2007 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-17386697

RESUMEN

Regularly new anabolic steroids appear on the black market. In most cases these substances are marketed on websites or are confiscated during inspections. 1,(5alpha)-Androstene-17beta-ol-3-one, also known as 1-testosterone, is one of these substances presented to body-builders as a nutritional supplement or a pro-hormone. 1-Testosterone closely resembles the natural hormone testosterone except for a 1,2-double bound instead of a 4,5-double bound. 1-Androstene-3beta,17beta-diol is transformed into 1-testosterone after oral administration. 1-Testosterone, 1-androstene-3beta,17beta-diol and some other related 'new' anabolic steroids were studied with gas chromatography coupled to mass spectrometry (GC-MS) and Liquid chromatography coupled to tandem mass spectrometry (LC-MS2) methods. Similarities in spectra to known analytes, which may lead to pitfalls in the interpretation of the derivatised analytes, are discussed.


Asunto(s)
Anabolizantes/análisis , Andrógenos/análisis , Cromatografía de Gases/métodos , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Esteroides/análisis , Testosterona/análogos & derivados , Testosterona/análisis , Administración Oral , Androstenodiol/análisis , Cromatografía Líquida de Alta Presión/métodos , Doping en los Deportes , Cromatografía de Gases y Espectrometría de Masas , Modelos Químicos , Detección de Abuso de Sustancias/métodos , Testosterona/química , Levantamiento de Peso
3.
Vet Res Commun ; 30(6): 577-85, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16838200

RESUMEN

The continuous introduction of new products used as growth promoters in animal husbandry, for sports doping and as products for body-building requires residue laboratories to initiate research on developing a strategy for the identification of 'unknown' components. In this study, a strategy is presented for elucidating the identity, the structure and the possible effects of illegal estrogenic compounds in an unidentified water-based solution. To obtain complete information on the composition and activity of the unidentified product, a multidisciplinary approach was needed. A case-study is described with a 'solution X' found during a raid. First, in vivo techniques (animal trials with mice, anatomical and histological research) were combined with in vitro techniques (the yeast estrogenic screen (YES)). In a later stage of the investigation, HPLC-fractionation, liquid chromatography-multiple mass spectrometry (LC-MSn) and gas chromatography-multiple mass spectrometry (GC-MSn) were used. Finally, the identity of 'solution X' was confirmed in a very low concentration range (10 ng/L estrone and 400 ng/l ethinyloestradiol).


Asunto(s)
Residuos de Medicamentos/análisis , Estrógenos/análisis , Crianza de Animales Domésticos/normas , Animales , Bioensayo/veterinaria , Cromatografía Líquida de Alta Presión , Seguridad de Productos para el Consumidor , Estrógenos/administración & dosificación , Femenino , Contaminación de Alimentos/análisis , Cromatografía de Gases y Espectrometría de Masas , Masculino , Espectrometría de Masas , Carne/análisis , Ratones , Distribución Aleatoria , Aumento de Peso
5.
Food Addit Contam ; 22(9): 798-807, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16192066

RESUMEN

Boldenone (1,4-androstadiene-17-ol-3-one, Bol) has been the subject of a heated debate because of ongoing confusion about its endogenous or exogenous origin when detected in one of its forms in faecal or urine samples from cattle. An expert report was recently written on the presence and metabolism of Bol in various animal species. Androstadienedione (ADD) is a direct precursor of 17beta-boldenone (betaBol). It is a 3,17-dione; ssBol is a 17-ol-3-one. Not much is published on 1,4-androstadiene-3,17-diol, which is a 3,17-diol (ADL). If animals were exposed for a longer period to one of these analytes, a metabolic pathway would be initiated to eliminate these compounds. Similar to recent testosterone metabolism studies in the aquatic invertebrate Neomysis integer, ADD, ssBol and ADL could also be eliminated as hydroxymetabolites after exposure. The presence of 11-keto-steroids or 11-hydroxy-metabolites in faecal samples can interfere with a confirmation method by gas chromatography-negative chemical ionization mass spectrometry (GC-NCI-MS), after oxidation of corticosteroids with a double bond in the A-ring (e.g. prednisolone or its metabolite prednisone). The presence of androstadienetrione (ADT) in faecal samples of cattle has never been reported. The origin of its presence can be explained through different pathways, which are presented in this paper.


Asunto(s)
Androstadienos/análisis , Bovinos/metabolismo , Heces/química , Corticoesteroides/metabolismo , Animales , Cromatografía Liquida/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Espectrometría de Masas/métodos , Oxidación-Reducción
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