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1.
Artigo em Inglês | MEDLINE | ID: mdl-34224963

RESUMO

Anti-doping analysis requires an exceptional level of accuracy and precision given the stakes that are at play. Current methods rely on the application of chromatographic techniques linked with mass spectrometry to provide this. However, despite the effectiveness of these techniques in achieving good selectivity and specificity, some issues still exist. In order to reach the minimum required performance level as set by WADA, labs commonly use selective monitoring by quadrupole mass spectrometry. This can be potentially fooled through the use of masking agents or by moving the peaks, as often only a small portion of the spectrum is used for analysis. Further issues exist in the inability to detect new or modified compounds, or to reanalyse samples/spectra. One technique that could overcome these problems is that of comprehensive 2D chromatography. Here a second separation column is employed to generate greater separative power. Compared to conventional separation, GCxGC allows for a greater peak capacity (i.e., number of peaks that can be resolved within a given time) and greater separation of coeluting compounds, which makes the technique promising for the complex task required in anti-doping. When combined with Time of Flight Mass Spectrometry this technique demonstrates vast potential allowing for full mass range datasets to be obtained for retroactive analysis. Similarly, LCxLC provides improvements in resolving power compared to its 1D counterpart and can be used both online as part of the analysis or offline solely as a purification step. In this review we summarise the work in this field so far, how comprehensive chromatography has been applied to anti-doping studies, and discuss the future application for this technique.


Assuntos
Anabolizantes/análise , Cromatografia Gasosa/métodos , Cromatografia Líquida/métodos , Dopagem Esportivo , Drogas Ilícitas/análise , Animais , Cavalos , Humanos
2.
Analyst ; 145(14): 4716-4736, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32500888

RESUMO

The problem posed by anti-doping requirements is one of the great analytical challenges; multiple compound detection at low ng ml-1 levels from complex samples, with requirements for exceptional confidence in results. This review surveys the design, synthesis and application of molecularly imprinted polymers (MIPs) in this field, focusing on the templating of androgenous anabolic steroids (AASs), as the most commonly abused substances, but also other WADA prohibited substances. Commentary on the application of these materials in detection, clean-up and sensing is offered, alongside views on the future of imprinting in this field.

3.
Scott Med J ; 59(3): 143-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25187193

RESUMO

In summer 2014, the world watched as Glasgow hosted the 2014 Commonwealth Games and athletes pushed the boundaries of human performance. Sport has developed into a multi-billion pound industry leading to the development of a 'win at any cost' mentality in some individuals. The abuse of performance-enhancing drugs has developed into a sophisticated arms race between those unfairly enhancing performance and those wishing to preserve the dignity of sport and the health of the competitors. The challenge for the Commonwealth games organising committee was to ensure that competition remained fair and that athletes were kept safe. The athlete biological passport is a system implemented by the World Anti-Doping Agency directed towards enhancing the identification of those athletes accountable for the misuse of performance-enhancing substances. This article exemplifies which drugs are currently being exploited and how the athlete biological passport has evolved to improve their detection.


Assuntos
Atletas , Dopagem Esportivo , Substâncias para Melhoria do Desempenho , Detecção do Abuso de Substâncias/métodos , Atletas/história , Biomarcadores/sangue , Biomarcadores/urina , Dopagem Esportivo/história , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Substâncias para Melhoria do Desempenho/sangue , Substâncias para Melhoria do Desempenho/história , Substâncias para Melhoria do Desempenho/urina
4.
J Clin Endocrinol Metab ; 89(12): 6030-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15579755

RESUMO

Androstenedione as a dietary supplement has been targeted at the sporting community, but there are limited data regarding its effects on plasma androgens in young women. A double-blind, cross-over study was undertaken involving 10 women (20-32 yr) using hormonal contraception. Because contamination of supplements has been reported, an in-house oral formulation was prepared containing purified androstenedione, the control being lactose only. After oral administration of a single dose of androstenedione (100 mg), blood was collected frequently up to 8 h and at 24 h. Maximum plasma androgen concentrations observed between volunteers were well above the upper limit of reference ranges for women, being 121-346 nmol/liter for androstenedione, 14-54 nmol/liter for testosterone (T), 11-32 nmol/liter for 5alpha-dihydrotestosterone, and 23-90 nmol/liter for 3alpha-androstanediol glucuronide. The free androgen index and T concentration changed in a similar manner. The mean change in area under the plasma concentration-time curve (0-24 h), compared with control data were: androstenedione approximately 7-fold, T approximately 16-fold, 5alpha-dihydrotestosterone approximately 9-fold, and 3alpha-androstanediol glucuronide approximately 5-fold; the mean conversion ratio of androstenedione to T was 12.5% (range 7.8-21.6%). Increases in T area under the plasma concentration-time curve were correlated with SHBG concentration (r = 0.80; P = 0.005). Formulation characteristics and SHBG levels appear to be important factors when considering plasma androgen increases after acute androstenedione administration.


Assuntos
Androgênios/sangue , Androstano-3,17-diol/análogos & derivados , Androstenodiona/administração & dosagem , Anticoncepcionais Orais Hormonais/farmacologia , Administração Oral , Adulto , Androstano-3,17-diol/sangue , Androstenodiona/farmacologia , Área Sob a Curva , Estudos Cross-Over , Di-Hidrotestosterona/sangue , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Imunoensaio , Lactose/farmacologia , Concentração Osmolar , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue , Fatores de Tempo
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