Combining Credentialing, Ion Mobility Spectrometry, and Tandem MS (IMS-MS/MS) to Detect, Identify and Validate Metabolites in Untargeted Analyses

In this work we evaluate the analytical utility of incorporating ion mobility spectrometry (IMS) as an additional separation and characterization mechanism for isotopologue workflows. As IMS separations conserve mobility behavior of isotopically labeled analytes, utilizing IMS in this untargeted ‘omics experiment provides intuitive discovery of compounds directly correlated to biological activity via feature finding, MS/MS characterization, and collision cross section (CCS) database matching. We demonstrate the additional analytical selectivity IMS separations provide in untargeted isotopologue experiments, wherein a preliminary dataset of 30 endogenous metabolites are putatively annotated from isotopically labeled Escherichia coli (E. coli) cultures analyzed by LC-IMS-MS/MS. Metabolites annotations were based on several molecular descriptors, including accurate mass measurement, carbon number, annotated MS/MS spectra, and CCS, and collectively illustrate the potential of incorporating IMS technology into isotopologue workflows.

For Research Use Only. Not for use in diagnostic procedures.