J.E. Krechmer, et al.
Atmos. Meas. Tech., 2016, DOI:10.5194/amt-9-3245-2016
IMS-MS is rapidly being adopted by bioanalytical researchers. The promise of being able to quickly separate isomeric compounds is especially interesting for the fields of metabolomics and lipidomics where different isomers sometimes exhibit huge differences in biological activity.
Adding an IMS dimension to MS analyses could also be of major benefit for atmospheric measurements. There, researchers are often faced with the problem that many molecules from organic aerosols cannot be sufficiently well identified based on MS alone. Yet, these identifications, especially for isomeric molecules, are crucial for establishing chemical mechanisms that inform climate models. IMS-MS instruments could consequently greatly improve the understanding of reactions in the atmosphere.
Taken together, the small size, robust construction, and high IMS resolving power of the TOFWERK IMS-TOF suggest an opportunity to bring the advantages of IMS-MS to the challenging research environments that are typical of atmospheric research. Such capability is demonstrated by Krechmer et al. in their current paper in Atmospheric Measurement Techniques.
Elemental composition and molecular structure of organic species in ambient air were simultaneously characterized with a TOFWERK IMS-TOF that was run continuously for multiple weeks at a remote Alabama field site during the 2013 Southern Oxidant and Aerosol Study (SOAS) campaign. The IMS-TOF data set yielded many exciting results, including differentiation of organosulfates derived from isomers of isoprene epoxydiols (IEPOX). Fragmentation of precursor ions by collisionally induced dissociation (CID) was used to validate MS peak assignments, elucidate structures of oligomers, and confirm the presence of the organosulfate functional group.
The gas and aerosol IMS–TOF data sets provide valuable chemical information that cannot be obtained from high resolution mass spectrometry alone.