Ion mobility spectrometry in metabolite profiling of complex plant extracts

Plant extracts are composed of hundreds of compounds, which vary widely in structure, physicochemical properties and concentration. LC-MS systems that provide high performance separation and detection are routinely used to obtain detailed information on the composition of such complex extracts in the frame of metabolite profiling studies. There is however a need for better resolution in both LC and MS dimensions to better detect if possible 'all' metabolites in a given natural extract. Ion mobility spectrometry (IMS) represents an additional dimension to LC-MS, based on the separation of the ions in the gas phase according to their chemical and physical interactions with a drift gas [2]. Coupled with a TOF-MS, IMS offers a high speed (milliseconds) separation capable of resolving many of the isomers and stereoisomers not easily separated by LC. In this work, the potential of IMS for the deconvolution of isomeric flavonoids has been studied, and the capacities and complementarities of IMS-TOF and UHPLC-TOF-MS platforms for the metabolite profiling of the medicinal plant Ginkgo biloba have been compared.