Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 2 de 2
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Chromatogr A ; 1628: 461445, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822984

RESUMO

Anabolic androgenic steroids (AAS) have been the most commonly abused substances taken by not only professional sportsmen but also recreational bodybuilders. The detection of micro-dose testosterone (T) misuse is particularly challenging as it possesses pseudo-endogenous origin and is sometimes impossible to be identified in urine samples. Dried blood (DB) obtained by finger pricking has been proven to be an alternative matrix for better correlating to physiological responses. Moreover, the introduction of the volumetric absorptive microsampling (VAMS) technology allows overcoming some major limitations of spotting blood onto a filter paper card. In this work, a fast and sensitive GC-MS/MS method was developed and validated for the quantification of AAS in DB collected by means of VAMS. T and the eight top abused synthetic AAS, namely nandrolone, boldenone, mesterolone, drostanolone, metenolone, metandienone, oxandrolone, and dehydrochloromethyl T were selected as the target analytes. The method based on VAMS exhibited good precision, accuracy as well as stability, and superior extraction recoveries over the punched DB spots reported in the literature. The chromatographic separation was achieved within 6.4 min and the detection limit is as little as 50 fg (i.e. able to detect 0.10 ng mL-1 in 20 µL of DB). Confirmed by forty real blood samples, the Deming regression and Bland-Altman analysis revealed that the VAMS DB could be employed for quantifying blood T level in agreement with using the serum specimen. The feasibility of the method was then successfully proven by the analysis of samples collected from a three-arm T administration trial. Our results highlighted that DB total T was a sensitive indicator for identifying transdermal micro-dosing of T. In the groups of receiving T gel administration, T concentrations could rise up to ten times higher than the baseline at 9 h after the application. As a future step, this approach is being expanded to a large cohort screening of bodybuilders at gym and ultimately may allow universal applications on monitoring sports drug misuse.


Assuntos
Androgênios/sangue , Teste em Amostras de Sangue Seco/métodos , Monitoramento de Medicamentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em Tandem , Congêneres da Testosterona/sangue , Testosterona/análise , Humanos
2.
Drug Test Anal ; 10(11-12): 1722-1727, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30381908

RESUMO

Anabolic androgenic steroids (AAS) are the most widely abused class of drugs by athletes and thus represent a significant problem to the anti-doping community. Confirmation of a doping violation for AAS cannot always be based on their presence alone due to the endogenous production of some steroids. Both testosterone (and its metabolites) and the major diagnostic metabolite of nandrolone (19-norandrosterone) are produced endogenously. Gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) is used in such cases to differentiate between the administration of a synthetic preparation and endogenous steroid production by measurement of their differing carbon isotope (13 C/12 C) ratio. The purpose of this study was to investigate the availability of steroid preparations in the UK with a 13 C content analytically indistinguishable from that of endogenous steroids. Fourteen preparations containing nandrolone (n = 9) and testosterone (n = 5) were analyzed. The δ13 C values were determined using GC-C-IRMS and the identity of the steroid preparations was confirmed using gas chromatography-mass spectrometry (GC-MS). Ten steroid preparations displayed δ13 C values within the range expected for synthetic steroids (less than -27‰). However, four nandrolone preparations displayed δ13 C values that overlap with the values considered to be endogenous in origin (range: -26 to -16‰). Misuse of these preparations could prevent the confirmation of nandrolone administration using GC-C-IRMS in anti-doping cases.


Assuntos
Anabolizantes/análise , Androgênios/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Nandrolona/análise , Testosterona/análise , Isótopos de Carbono/análise , Dopagem Esportivo , Estranos/análise , Humanos , Esteroides/análise , Detecção do Abuso de Substâncias/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...