Isotope Dilution Technique for the Estimation of <i>l</i>-Alpha-[2-³H]-Acetylmethadol and Its Metabolites in Biological Samples

Abstract

An isotope dilution technique for the determination of l-α-(2-³H)-acetylmethadol and its metabolites from biological samples is described. The parent drug and metabolites were extracted from biological samples with chlorobutane after the addition of unlabeled internal standards. The extracts were purified by two-dimensional thin-layer chromatography for quantification by gas-liquid chromatography and scintillation counting. Dinoracetylmethadol (NNAM) was found to be converted to 6-acetamido-4,4-diphenyl-3-heρtanol (AMIDE) during the extraction procedure. The conversion of NNAM to AMIDE was confirmed by gas chromatography-mass spectrometry.