biostudies-literaturePellegrinelli RPSwiss National Science Foundation?cole Polytechnique F?d?rale de LausanneEuropean Research Council859-864https://www.ebi.ac.uk/biostudies/studies/S-EPMC9074103biostudies-literatureUnknown33(5)Determining the primary structure of glycans remains challenging due to their isomeric complexity. While high-resolution ion mobility spectrometry (IMS) has recently allowed distinguishing between many glycan isomers, the arrival-time distributions (ATDs) frequently exhibit multiple peaks, which can arise from positional isomers, reducing-end anomers, or different conformations. Here, we present the combination of ultrahigh-resolution ion mobility, collision-induced dissociation (CID), and cryogenic infrared (IR) spectroscopy as a systematic method to identify reducing-end anomers of glycans. Previous studies have suggested that high-resolution ion mobility of sodiated glycans is able to separate the two reducing-end anomers. In this case, Y-fragments generated from mobility-separated precursor species should also contain a single anomer at their reducing end. We confirm that this is the case by comparing the IR spectra of selected Y-fragments to those of anomerically pure mono- and disaccharides, allowing the assignment of the mobility-separated precursor and its IR spectrum to a single reducing-end anomer. The anomerically pure precursor glycans can henceforth be rapidly identified on the basis of their IR spectrum alone, allowing them to be distinguished from other isomeric forms.Journal of the American Society for Mass SpectrometryA New Strategy Coupling Ion-Mobility-Selective CID and Cryogenic IR Spectroscopy to Identify Glycan Anomers.PMC9074103788697206021_177004200020_184838Pellegrinelli RPBen Faleh AWarnke SYue LCarrascosa EBansal PRizzo TRfalseA New Strategy Coupling Ion-Mobility-Selective CID and Cryogenic IR Spectroscopy to Identify Glycan Anomers.Determining the primary structure of glycans remains challenging due to their isomeric complexity. While high-resolution ion mobility spectrometry (IMS) has recently allowed distinguishing between many glycan isomers, the arrival-time distributions (ATDs) frequently exhibit multiple peaks, which can arise from positional isomers, reducing-end anomers, or different conformations. Here, we present the combination of ultrahigh-resolution ion mobility, collision-induced dissociation (CID), and cryogenic infrared (IR) spectroscopy as a systematic method to identify reducing-end anomers of glycans. Previous studies have suggested that high-resolution ion mobility of sodiated glycans is able to separate the two reducing-end anomers. In this case, Y-fragments generated from mobility-separated precursor species should also contain a single anomer at their reducing end. We confirm that this is the case by comparing the IR spectra of selected Y-fragments to those of anomerically pure mono- and disaccharides, allowing the assignment of the mobility-separated precursor and its IR spectrum to a single reducing-end anomer. The anomerically pure precursor glycans can henceforth be rapidly identified on the basis of their IR spectrum alone, allowing them to be distinguished from other isomeric forms.2022-01-01T00:00:00Z2022 May2025-04-18T14:14:12.418Z2025-04-04T20:22:05.384ZS-EPMC90741033543799510.1021/jasms.2c00043