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2.
Talanta ; 82(4): 1581-7, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20801376

RESUMO

Gestrinone is a synthetic steroid hormone with anti-estrogenic and anti-progesterone properties. It is used to treat endometriosis, shrink uterine fibroids and reduce menorrhagia; besides, it has been investigated for use as contraceptive. Also, due to its anabolic effects, it has been included in the banned list of performance enhanced drugs in sport. Polyclonal antibodies raised against bovine serum albumin coupled to gestrinone 3-carboxymethyloxime (3OCMO-G) were used to develop two highly sensitive and specific enzyme-linked immunosorbent assays for gestrinone. One of them, based on direct format, shows a detection limit (LD) of 0.09+/-0.03 ng L(-1). The second assay, hapten-protein coating format, can detect until (LD) 0.14+/-0.05 ng L(-1). Both immunoassays were also highly specific, showing negligible or no cross-reactivity to other anabolic steroids. The developed ELISAs detected lower amounts of gestrinone than those determined by the reference chromatographic HPLC/MS/MS methods. The direct format was applied to quantify this steroid in spiked human urine without sample pre-treatment, with recovery values between 76 and 122%.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Gestrinone/análise , Cromatografia Líquida de Alta Pressão , Reações Cruzadas , Humanos , Limite de Detecção , Espectrometria de Massas em Tandem
3.
Bioanalysis ; 1(8): 1475-89, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21083096

RESUMO

Anabolic steroids are the main abused class of prohibited substances in doping control. These steroids are associated with enhancement of muscular mass and aggressiveness, resulting in increased performance. Chromatography and MS have a key role among methods developed to detect anabolic steroids in doping control laboratories. However, the classical analytical approach fails in detection of the so-called 'designer steroids'. This review focuses on the rise of tetrahydrogestrinone, a drug that became synonymous with designer steroids. The reasons why classical methods fail in tetrahydrogestrinone detection are discussed and how the detection was implemented is shown. Alternative strategies for detection of new drugs designed to cheat current analytical methodology are highlighted. Concern for the abuse of veterinary designer drugs and supplements is also acknowledged.


Assuntos
Anabolizantes/análise , Drogas Desenhadas/análise , Gestrinone/análogos & derivados , Detecção do Abuso de Substâncias/métodos , Drogas Veterinárias/análise , Técnicas de Química Analítica/métodos , Suplementos Nutricionais/análise , Dopagem Esportivo , Gestrinone/análise , Humanos
4.
Anal Chim Acta ; 586(1-2): 137-46, 2007 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-17386705

RESUMO

A liquid chromatography/time-of-flight mass spectrometry (LC/TOFMS) method was developed using the latest high-resolution LC column technology, the ultra performance liquid chromatography (UPLC), and electrospray ionization (ESI) in the positive ion mode. Gradient UPLC separation conditions were optimized for a group of 22 analytes comprising 17 glucocorticosteroids, specific designer steroids such as tetrahydrogestrinone (THG) and specific beta2-agonists such as formoterol. The UPLC/TOFMS separation obtained required 5.5 min only for all the substances tested. Even the critical pair of dexamethasone and betamethasone isomers was almost completely resolved. Thanks to the over 10,000 full-width at half maximum (FWHM) mass resolution and high mass accuracy features of TOFMS 50 mDa window accurate mass chromatograms could be reconstructed for the individual analytes. Sensitive screening in human and calf urine samples fortified at the glucocorticosteroids minimum required performance limit (MRPL) of 30 microg L(-1) (human urine, sports doping) and 2 microg L(-1) (calf urine, veterinary control) could be obtained. The potential of UPLC/TOFMS for confirmatory analysis was shown by determining the accurate mass of all compounds and fragment ions upon in-source collision-induced dissociation (CID) at different energies. The exact mass measurement errors for all glucocorticosteroids were found to be within 6 ppm. Considering veterinary control, limits of detection (LOD) and limits of quantification (LOQ) were determined for most of the analytes in calf urine and found to range from 0.1 to 3.3 and from 0.4 to 4.4 microg L(-1), respectively. The method can be easily extended with other banned substances of interest, as demonstrated by the addition of 21 beta2-agonists to the original analyte mixture in urine, without causing any interferences.


Assuntos
Corticosteroides/análise , Cromatografia Líquida/métodos , Dopagem Esportivo , Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , Urinálise/métodos , Medicina Veterinária/métodos , Corticosteroides/química , Animais , Bovinos , Drogas Desenhadas , Etanolaminas/análise , Fumarato de Formoterol , Gestrinone/análogos & derivados , Gestrinone/análise , Humanos , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray
5.
J Chromatogr A ; 1150(1-2): 215-25, 2007 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-16963059

RESUMO

Tetrahydrogestrinone, gestrinone and trenbolone are synthetic 19-norsteroids with androgenic properties sharing a labile conjugated ketotrienyl motif. Their LC-MS analyses tend to overcome classical derivatization problems, a shortcoming to the use of GC-MS. Therefore, alternative derivatization procedures were evaluated. The procedure with methoxylamine: pyridine followed by TMSImid: MSTFA gave the best results. This is attributed to the stability of the MO-TMS derivatives hindering the formation of artifacts and tautomerism. A full method is presented including SPE, hydrolysis and liquid-liquid extraction. It was possible to confirm the analytes below 2 ng/mL in urine, being the method robust and cost effective also for screening proposes.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Gestrinone/análogos & derivados , Gestrinone/urina , Acetato de Trembolona/urina , Adulto , Feminino , Gestrinone/análise , Gestrinone/química , Humanos , Estrutura Molecular , Reprodutibilidade dos Testes , Acetato de Trembolona/análise , Acetato de Trembolona/química
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