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1.
Rapid Commun Mass Spectrom ; 29(4): 367-84, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-26406349

RESUMO

RATIONALE: Doping analysis is a two-step process consisting of a screening step for prohibited substances and a confirmation step to verify the presence of specific substances found during the screening. The entire process must be performed within a limited time period, but traditional screening procedures commonly employ separate analytical methods for each class of prohibited substances being screened and thus require a great deal of human resources and instrumentation. A single simple and rapid multiresidue analytical method that could accommodate multiple classes of prohibited substances would be extraordinarily useful in doping analyses. METHODS: Urine samples were extracted via two consecutive liquid-liquid extractions at different pH values following enzymatic hydrolysis. Analyses were performed by ultrafast liquid chromatography/triple-quadrupole mass spectrometry with polarity switching and time-dependent selected reaction monitoring. RESULTS: We developed a rapid multiresidue screening and confirmation method for efficient high-throughput doping analyses. The present method was validated with regard to the limits of detection (0.01-100.0 ng/mL for screening analyses and 0.2-500.0 ng/mL for confirmation assays), matrix effects (48.9-118.9%), recovery (20.6-119.7%) and intra- (0.6-17.6%) and inter-day (4.0-20.0%) precision. CONCLUSIONS: A multiresidue analytical method was developed and validated for screening and confirming the presence of performance-enhancing drugs. A total of 210 substances from diverse classes of prohibited substances were successfully identified with an analytical run time of 10 min.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Substâncias para Melhoria do Desempenho/urina , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/economia , Humanos , Limite de Detecção , Extração Líquido-Líquido , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/economia
2.
Drug Test Anal ; 6(11-12): 1174-85, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25382000

RESUMO

Metal ion coordination ionspray (M(+) CIS) ionization is a powerful technique to enhance ionization efficiency and sensitivity. In this study, we developed and validated an analytical method for simultaneous ionization and analysis of 84 anabolic androgenic steroids (65 exogenous and 19 endogenous) using liquid chromatography-silver ion coordination ionspray/triple-quadrupole mass spectrometry (LC-Ag(+) CIS/MS/MS). The concentrations of silver ions and organic solvents have been optimized to increase the amount of silver ion coordinated complexes. A combination of 25 µM of silver ions and methanol showed the best sensitivity. The validation results showed the intra- (0.8-9.2%) and inter-day (2.5-14.9%) precisions, limits of detection (0.0005-5.0 ng/mL), and matrix effect (71.8-100.3%) for the screening analysis. No significant ion suppression was observed. In addition, this method was successfully applied to analysis of positive samples from suspected abusers and useful for the detection of the trace levels of anabolic steroids in human urine samples.


Assuntos
Anabolizantes/urina , Androgênios/urina , Dopagem Esportivo , Prata/urina , Esteroides/urina , Cromatografia Líquida de Alta Pressão , Humanos , Padrões de Referência , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray
3.
Anal Chim Acta ; 631(1): 54-61, 2009 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-19046678

RESUMO

In this study, a new sampling method called headspace mulberry paper bag micro solid phase extraction (HS-MPB-mu-SPE) combined to gas chromatography-mass spectrometry has been applied for the analysis of volatile aromas of liquid essential oils from Bulgarian rose and Provence lavender. The technique uses an adsorbent (Tenax TA) contained in a mulberry paper bag, minimal amount of organic solvent. Linearities for the six-points calibration curves were excellent. LOD values were in the rage from 0.38 ng mL(-1) to 0.77 ng mL(-1). Overall, precision and recovery were generally good. Phenethyl alcohol and citronellol were the main components in the essential oil from Bulgarian rose. Linalyl acetate and linalool were the most abundant components in the essential oils from true lavender or lavandin. Additionally, the relative extraction efficiencies of proposed method have been compared with HS-SPME. The overall extraction efficiency was evaluated by the relative concentration factors (CF) of the several characteristic components. CF values by HS-MPB-mu-SPE were lower than those by headspace solid phase microextraction (HS-SPME). The HS-MPB-mu-SPE method is very simple to use, inexpensive, rapid, requires small sample amounts and solvent consumption. In addition, this method allowed combining of extraction, enrichment, and clean-up in a single step. HS-MPB-mu-SPE and GC/MS is a promising technique for the characterization of volatile aroma compounds from liquid essential oils.


Assuntos
Lavandula/química , Morus/química , Odorantes/análise , Óleos Voláteis/análise , Papel , Rosa/química , Microextração em Fase Sólida/métodos , Adsorção , Bulgária , França , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/química , Fenóis/química , Polímeros/química , Reprodutibilidade dos Testes , Volatilização
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