Simple methods for the synthesis of twenty different, highly enriched deuterium labelled steroids, suitable as internal standards for isotope dilution mass spectrometry

Abstract

Twenty diferent steroids, labelled with two to four deuterium atoms have been synthesized according to simple procedures. Labelling techniques have been adapted or modified to make them more efficient for the production of internal standards with high isotope enrichments. The stability of the carbon–deuterium bonds has been checked according to the following criteria: storage time in non-protic solvents, incubation in biological samples and derivatization reaction conditions. Care has been taken not to introduce more than four deuterium atoms per molecule, otherwise retention time decrease becomes significant. The limitations of the gas chromatographic mass spectrometric technique for the accurate measurement of the isotope composition of these highly enriched deuterium labelled compounds has been discussed in relation to the existing carrier effect.