Ion Trap mass spectrometer coupled to an HPLC including PC and nitrogen generator

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The ion trap mass spectrometer will primarily be used for the de novo structural elucidation of primary and secondary plant compounds, the validation of known substances and the quantification of these plant compounds. A particular advantage of the ion trap mass spectrometer is the sequential fragmentation of the analyte into daughter ion(s). Multiple fragmentation (MSn) cannot be achieved with any other type of mass spectrometer. The ion trap mass spectrometer is coupled to a HPLC, which is suitable for high sample throughput.The ion trap mass spectrometer is used in various projects, e.g. (1) for de novo structure elucidation and quantification of complex flavonoid glycosides and hydroxycinnamic acid derivatives. Due to the lack of reference substances for complex compounds of this group of substances, a chromatographic analysis only is not possible. (2) to validate carotenoid stereoisomers for which no reference substances are available. In many cases, measurement with a mass spectrometer can provide additional information in this case, since chromatographic methods cannot provide sufficient differentiation. Their ionization is only possible with the help of the corona discharge needle of an APCI source without additives. (3) to validate the structural proposals of chlorophylls and their degradation products, which occur in very low concentrations. (4) to protect the proposed structure of glucosinolates which are precursors for health-protective isothiocyanates or other glucosinolate degradation products. (5) for de novo structure elucidation and validation of the proposed structure of sesquiterpene lactones, alkaloids and polyacetylenes, which are chemically diverse bitter substances in plants. (6) for the analysis of saponins in terms of qualification and quantification, since these substances cannot be detected by chromatography due to the lack of chromophores. (7) for the analysis of intact phospholipids, which has not yet been successful. Since the compounds are isotopically labelled, a high resolution of the isotope peaks is advantageous. (8) for the analysis of polysaccharides without derivatisation or total hydrolysis. Sequential fragmentation can produce oligosaccharides from the polysaccharides, which can be used for analysis and thus speed up the overall analysis. For these investigations, measurements up to MS11 are conceivable and will be tested.The ion trap mass spectrometer is installed in the HPLC-MS Service Unit of the Faculty of Agricultural Sciences.