Bull. Spec. CORESTA Congress, Jerez de la Frontera, 1992, p. 101, ST27, ISSN.0525-6240
Applications of new tandem mass spectrometry methods to analysis of tobacco-related materials
Philip Morris USA, Richmond, VA, USA
In recent years new mass spectrometry methods including soft ionization and tandem experiments have been developed which have been shown to be highly effective for analyzing complex mixtures and thermally labile polar molecules, analytical challenges quite familiar to the tobacco chemist. We have shown in earlier work that fast atom bombardment (FAB) analysis of the tobacco-specific compound solanesol doped with lithium ions produces abundant (M+Li)+ ions. Subsequent high energy collisional activation of this (M+Li)+ ion in the conventional tandem (MS/MS) product ion experiment yielded a definitive finger print spectrum for solanesol including ions related to high mass fragments. Certainly this is very useful but two difficulties may arise as this methodology is applied to complex samples such as those related to tobacco. First many large molecules produce limited fragmentation in the MS/MS experiment. Thus, although some structural information is obtained, fragment s of several hundred amu may be formed. The MS/MS/MS (MS3) experiment which we have recently developed on the double reverse four sector mass spectrometer permits another stage of MS/MS. Hence additional information regarding the substructure of these large molecules can be obtained. Secondly, although the MS/MS experiment is quite useful for mixture analysis, very complex samples may generate undesirable matrix effects. TLC is an established method for rapid and simple separation of natural products. Coupling this technique with FAB/MS or FAB/MS/MS facilitates obtaining highly specific characterization of given components from complex mixtures. Solanesol and commercially available glycosides and dinucleotides are used as examples to demonstrate the enhancement of molecular information that may be obtained from these methods.