Chiral analysis by online coupling of reversed-phase liquid chromatography to gas chromatography and mass spectrometry

Enantiomeric composition of selected chiral compounds present in complex mixtures is determined by using the online coupling of reversed-phase liquid chromatography (LC) to gas chromatography (GC) and mass spectrometry. Integration of sample preparation into GC analysis, in a completely automated way, is achieved by means of the effective clean-up resulting from both the LC fractionation step and the eluent elimination provided by the through oven transfer adsorption desorption system used for LC–GC interfacing. The possibilities of the technique are illustrated through some examples concerning the stereodifferentiation in essential oils of major and minor chiral compounds via LC–GC transfer of different volume fractions, ranging from 0.5 to 1.9 ml, which show the significance of the window size for the determination of enantiomeric profiles. Chirality 24:420–426, 2012. © 2012 Wiley Periodicals, Inc.