A Multidimensional Lipidomics Method: HILIC Coupled with Ion Mobility Enable Time-of-Flight Mass Spectrometry

K E Y W O R D S Lipids, lipidome, metabolomics, lipidomics, ion mobility spectrometry, Hydrophilic interaction chromatography (HILIC), HDMS Compare, T-WaveTM Technology A P P L I C AT IO N B E N E F I T S Combining HILIC-UPLC liquid phase separation with gas phase ion mobility mass spectrometry to achieve a multi-dimensional characterization of lipids in complex mixtures enhances profiling of lipids in biological samples. IN T RO DU C T IO N One of the main challenges for a global lipid analysis (lipidomics) is the separation of the wide array of lipid species present in biological samples (Figure 1). Such a separation is not achievable using a single chromatographic dimension such as reversedor normal-phase separation methods. Normalphase UPLC separates lipid classes based on their polar head group, whereas reversed-phase separates lipids according to their acyl chain length and number of double bonds. Hydrophilic interaction chromatography (HILIC) separation has been proposed as an alternative to normal-phase separation, offering better MS compatibility and using less toxic solvents. Recently, a two-dimensional separation using HILIC and reversed-phase has been proposed to maximize the separation of the lipidome before MS detection.