Simultaneous determination of blood concentrations of methohexital and its hydroxy metabolite by gas chromatography and identification of 4′-hydroxymethohexital by combined gas—liquid chromatography—mass spectrometry

doi:10.1016/S0378-4347(00)86074-0

Journal of Chromatography B: Biomedical Sciences and Applications

Volume 226, Issue 2, 11 December 1981, Pages 403-412

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Abstract

A simple, sensitive and selective method is described for the simultaneous determination of low concentrations (less than 50 ng/ml) of underivatized methohexital and its hydroxy metabolite in small (0.1 ml) samples of human and rat plasma or whole blood by gas chromatography with nitrogen-selective detection.

Moreover, the main metabolite in rat and man was identified as 4′-hydroxymethohexital by comparison of chromatograms from gas—liquid chromatography (GLC) with data obtained from GLC—mass spectrometry and ¹H-nuclear magnetic resonance spectrometry of this metabolite, produced both by incubating methohexital with isolated rat liver microsomes and by isolating this metabolite from rat urine.

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Simultaneous determination of blood concentrations of methohexital and its hydroxy metabolite by gas chromatography and identification of 4′-hydroxymethohexital by combined gas—liquid chromatography—mass spectrometry

Abstract

Brit. J. Anaesth.

Brit. J. Anaesth.

J. Chromatogr.

Biochem. Pharmacol.

Anesthesiology

Clin. Pharmacol. Ther.

J. Pharmacol. Exp. Ther.