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Improved screening method for beta-blockers in urine using solid-phase extraction and capillary gas chromatography-mass spectrometry.

M S Leloux·E G de Jong·R A Maes
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Abstract

An improved screening method for beta-blockers in urine is proposed, involving enzymatic hydrolysis, solid-phase extraction and capillary gas chromatography-mass spectrometry. Several extraction methods for beta-blockers, such as conventional liquid-liquid and solid-phase extraction procedures, have been evaluated for at least eight beta-blockers. Additionally, the gas chromatographic properties and mass fragmentation of the trimethylsilyl-trifluoroacetyl, trifluoroacetyl and cyclic n-butylboronate derivatives of beta-blockers have been compared and evaluated with respect to their efficiency for screening urine. The resulting screening method proved to be a specific and sensitive procedure, enabling these analytes to be detected and identified up to 48 h after the administration of a dosage, usually encountered in doping cases.

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Adrenergic beta-AntagonistsGas Chromatography-Mass SpectrometryHumansHydrolysisJournal Article

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M S Leloux, E G de Jong, R A Maes. 1989-03-24. Improved screening method for beta-blockers in urine using solid-phase extraction and capillary gas chromatography-mass spectrometry.. https://doi.org/10.1016/s0378-4347(00)82960-6

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Adrenergic beta-Antagonists↗