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1.
Steroids ; 74(10-11): 803-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19409402

RESUMO

Boldenone is banned in the European Union (Directive 96/22/EC) as growth promoter for meat producing animals. Boldione (ADD), boldenone and boldenone esters (mainly the undecylenate form) are commercially available as anabolic preparations, either to the destination of human, horse or cattle. Since the late 90s, the natural occurrence of boldenone metabolites has been reported in cattle. According to EU regulation, the unambiguous demonstration of boldenone administration in bovine urine should be provided on the basis of boldenone identification in the corresponding conjugate fraction. An analytical method has been developed and validated according to current standards with main concern to the measurement of intact 17beta-boldenone-sulphate. The analytical procedure included direct extraction-purification of target analyte on octadecylsilyl cartridges and direct detection of phase II metabolite by liquid chromatography (negative electrospray), tandem mass spectrometry (QqQ) or high resolution mass spectrometry (Orbitrap). Decision limit (CCalpha) and detection capability (CCbeta) were respectively 0.2 microg L(-1) and 0.4 microg L(-1) on triple quadrupole and 0.1 microg L(-1) and 0.2 microg L(-1) on hybrid system. The method was successfully applied to the analysis of incurred samples collected in different experiments. 17beta-Boldenone-sulphate was measurable up to 36h after oral administration of boldione, and 30 days after 17beta-boldenone undecylenate intra-muscular injection. This conjugate form was never detected in non-treated animals, confirming its status of definitive candidate marker for boldenone administration in calf.


Assuntos
Anabolizantes/urina , Androstadienos/urina , Bovinos/urina , Ésteres/química , Detecção do Abuso de Substâncias , Sulfatos/urina , Testosterona/análogos & derivados , Anabolizantes/química , Anabolizantes/metabolismo , Anabolizantes/farmacocinética , Androstadienos/química , Androstadienos/metabolismo , Androstadienos/farmacocinética , Ração Animal , Animais , Cromatografia Líquida de Alta Pressão , Glucuronídeos/metabolismo , Cavalos , Humanos , Masculino , Taxa de Depuração Metabólica , Reprodutibilidade dos Testes , Extração em Fase Sólida , Sulfatos/administração & dosagem , Sulfatos/química , Sulfatos/metabolismo , Espectrometria de Massas em Tandem , Testosterona/administração & dosagem , Testosterona/química , Testosterona/metabolismo , Testosterona/farmacocinética , Testosterona/urina
2.
Anal Chim Acta ; 637(1-2): 178-84, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19286027

RESUMO

Ecdysteroids, which are steroid hormones in invertebrates, but are also present in plants, could be potentially used as anabolic agents in food-producing animals because of their growth-promoting properties. In this context, the metabolism of 20-hydroxyecdysone (20E) has been investigated in cattle in order to efficiently control its potential misuse. The analytical procedure involves purification on two solid-phase extraction cartridges (SPE octadecylsilyl and SPE silica) prior to detection based on liquid chromatography coupled to high resolution mass spectrometry in negative electrospray ionization mode (LC-(ESI-)-HRMS). Each new signal appearing on full-scan HRMS (30,000) during the analysis was investigated by tandem mass spectrometry (MS/MS). Comparison of the mass spectra pattern between 20E and potential metabolites has given informations on the chemical structures of the metabolites. This targeted approach, combining HRMS and MS(n) measurements on a linear trap in tandem with an orbital trap, allowed us to elucidate the structure of several 20E metabolites in calf urine: 14-deoxy-20-hydroxyecdysone, 20,26-dihydroxyecdysone and 14-deoxy-20,26-dihydroxyecdysone, the last of which had never previously been reported in bovine. The kinetics of elimination of these metabolites were investigated, and two of them were monitored by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) measurements over 6 days after 20E administration to calves, thus increasing the time-window for detection after 20E administration and thereby allowing for more efficient control of its misuse.


Assuntos
Anabolizantes/urina , Cromatografia Líquida de Alta Pressão/métodos , Ecdisterona/urina , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem/métodos , Administração Oral , Anabolizantes/isolamento & purificação , Anabolizantes/farmacocinética , Animais , Bovinos , Ecdisterona/isolamento & purificação , Ecdisterona/farmacocinética , Cinética , Masculino , Extração em Fase Sólida
3.
Rapid Commun Mass Spectrom ; 22(24): 4073-80, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19012355

RESUMO

Ecdysteroids, which are steroid hormones in invertebrates, but which are also present in plants, could potentially be used as anabolic agents in food-producing animals. The control of ecdysteroid misuse in cattle relies on the development of an efficient method for their detection in biological matrices at trace levels (microg L(-1)). In order to propose an analytical procedure dedicated to the identification of excreted 20-hydroxyecdysone (20E) in urine and faecal samples of breeding animals, a comparative study of the spectrometric behaviour of these compounds was carried out both by LC/(ESI-)/HRMS(n) (hybrid linear ion trap - orbital trap) and by LC/(ESI+)/MS/MS (triple quadrupole). This study revealed the formation of a large number of product ions both in positive and negative ion mode, corresponding to losses of water molecules and specific cleavages on the side chain. The sample preparation consisted of sequential purification on two solid-phase extraction cartridges (SPE octadecylsilyl and SPE silica). The detection limits were around 0.5 microg L(-1) in the selected reaction monitoring (SRM) mode and recoveries above 60% were obtained. The method was successfully applied to the analysis of real samples collected from calves treated with 60 mg 20E over 4 days. Analysis of the samples allowed the investigation of the kinetics of elimination of 20E in calf urine and determination of the time-frame for the control of potential abuse.


Assuntos
Ecdisterona/farmacocinética , Ecdisterona/urina , Espectrometria de Massas por Ionização por Electrospray/métodos , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem/métodos , Administração Oral , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Ecdisteroides/urina
4.
Steroids ; 71(13-14): 1078-87, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17084871

RESUMO

Boldenone is an androgenic steroid that improves the growth and food conversion in food producing animals. In most countries worldwide, this anabolic steroid is forbidden for meat production. Until recently, the control of its illegal use was based either on 17beta-boldenone or 17alpha-boldenone (its main metabolite in cattle) identification in edible tissues, hair, faeces or urine. Recent observations and data tend to demonstrate the natural occurrence (but not ubiquitous) in cattle of these steroids, making the analytical strategy of the control more complicated. We investigated the metabolism of boldenone in cattle after intramuscular and oral treatment of boldenone, boldenone esters and boldione. The central objective was to elucidate the structures of the main metabolites (phase I and phase II) in urine, with main objective to be further in position to compare boldenone urinary profiles of treated and non-treated animals. Nine metabolites have been identified, only four were present whatever the treatment and the administered boldenone source. Nevertheless, all of them have been detected at least once in non-treated animals which did not permit us to use them as biomarkers of an illegal treatment. At last, but not at least, all metabolites were found mainly glucuro-conjugated, and rarely sulfo-conjugated, with the only exception of 17beta-boldenone. Current investigations are showing the absence of 17beta-boldenone sulfoconjugate in non-treated animals; that would permit to distinguish non-treated from treated animals with boldione, boldenone and boldenone esters.


Assuntos
Androstadienos/administração & dosagem , Testosterona/análogos & derivados , Androstadienos/urina , Animais , Bovinos , Ésteres , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Testosterona/administração & dosagem , Testosterona/urina
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