Publications

Publications at URI

  • Wellalage, M. M.*; Fernando, M. T.*; Molino, E. M.; Ober, K.; Torres-Boy, A. Y.; Schultz, M.; Banor, N. D.; Lees, J.; Helden, G. v.; Thomas, D. A., Halide Coordination Motifs in Deep Eutectic Solvent Building Blocks Characterized by Helium Nanodroplet Infrared Action Spectroscopy. J. Phys. Chem. A 2026, Accepted. https://doi.org/10.1021/acs.jpca.6c02885 *Authors contributed equally
  • Wellalage, M. M.;  Fernando, M. T.;  Molino, E. M.;  Schultz, M.;  Banor, N. D.;  Ellis, N. A.; Thomas, D. A., Intermolecular Interactions Governing Extraction Efficiency of Polycyclic Thiophenes by Deep Eutectic Solvents. Energy Fuels 2025, 39 (51), 24065-24076. https://doi.org/10.1021/acs.energyfuels.5c04738
  • Schultz, M.; Banor, N. D.; Ober, K.; Torres-Boy, A. Y.; Fernando, M. T.; Wellalage, M. M.; Ellis, N. A.; Helden, G. v.; Thomas, D. A. Examining the Effect of an Anion-Binding Reagent on the Structure of Deprotonated Leucine Enkephalin Using Cryogenic-Ion Infrared Action Spectroscopy. J. Phys. Chem. A 2025, 129, 8303-8311. https://doi.org/10.1021/acs.jpca.5c03984
  • Schultz, M.; Ellis, N. A.; Banor, N. D.; Thomas, D. A. Complexation of diserinol isophthalamide with phosphorylated biomolecules in electrospray ionization mass spectrometry. Int. J. Mass Spectrom. 2025, 507, 117364. https://doi.org/10.1016/j.ijms.2024.117364
  • Schultz, M.; Parker, S. L.; Fernando, M. T.; Wellalage, M. M.; Thomas, D. A., Diserinol Isophthalamide: A Novel Reagent for Complexation with Biomolecular Anions in Electrospray Ionization Mass Spectrometry. J. Am. Soc. Mass Spectrom. 2023, 34 (4), 745-753. https://doi.org/10.1021/jasms.3c00010

Publications Prior to URI

  • Taccone, M. I.; Thomas, D. A.; Ober, K.; Gewinner, S.; Schöllkopf, W.; Meijer, G.; von Helden, G., Infrared action spectroscopy of the deprotonated formic acid trimer, trapped in helium nanodroplets. Phys. Chem. Chem. Phys. 2023, 25 (15), 10907-10916. https://doi.org/10.1039/D2CP05409D
  • Mucha, E.; Thomas, D.; Lettow, M.; Meijer, G.; Pagel, K.; von Helden, G., Spectroscopy of Small and Large Biomolecular Ions in Helium-Nanodroplets. In Molecules in Superfluid Helium Nanodroplets: Spectroscopy, Structure, and Dynamics, Slenczka, A.; Toennies, J. P., Eds. Springer International Publishing: Cham, 2022; pp. 241-280. https://doi.org/10.1007/978-3-030-94896-2_6
  • Thomas, D. A.; Taccone, M.; Ober, K.; Mucha, E.; Meijer, G.; von Helden, G. Helium Nanodroplet Infrared Action Spectroscopy of the Proton-Bound Dimer of Hydrogen Sulfate and Formate: Examining Nuclear Quantum Effects. J. Phys. Chem. A, 2021, 125, 9279–9287. https://doi.org/10.1021/acs.jpca.1c05705
  • Greis, K.; Mucha, E.; Lettow, M.; Thomas, D. A.; Kirschbaum, C.; Moon, S.; Pardo-Vargas, A.; von Helden, G.; Meijer, G.; Gilmore, K.; Seeberger, P. H.; Pagel, K. The Impact of Leaving Group Anomericity on the Structure of Glycosyl Cations of Protected Galactosides. ChemPhysChem, 2020, 21, 1905–1907. https://doi.org/10.1002/cphc.202000473
  • Lettow, M.; Grabarics, M.; Greis, K.; Mucha, E.; Thomas, D. A.; Chopra, P.; Boons, G.-J.; Karlsson, R.; Turnbull, J. E.; Meijer, G.; Miller, R. L.; von Helden, G.; Pagel, K. Cryogenic Infrared Spectroscopy Reveals Structural Modularity in the Vibrational Fingerprints of Heparan Sulfate Diastereomers. Anal. Chem. 2020, 92, 10228–10232. https://doi.org/10.1021/acs.analchem.0c02048
  • Thomas, D. A.; Chang, R.; Mucha, E.; Lettow, M.; Greis, K.; Gewinner, S.; Schöllkopf, W.; Meijer, G.; von Helden, G. Probing the Conformational Landscape and Thermochemistry of DNA Dinucleotide Anions via Helium Nanodroplet Infrared Action Spectroscopy. Phys. Chem. Chem. Phys. 2020, 22, 18400–18413. https://doi.org/10.1039/D0CP02482A
  • Lettow, M.; Grabarics, M.; Mucha, E.; Thomas, D. A.; Polewski, L.; Freyse, J.; Rademann, J.; Meijer, G.; von Helden, G.; Pagel, K. IR Action Spectroscopy of Glycosaminoglycan Oligosaccharides. Anal. Bioanal. Chem. 2020, 412, 533–537. https://doi.org/10.1007/s00216-019-02327-7
  • Marianski, M.; Mucha, E.; Greis, K.; Moon, S.; Pardo, A.; Kirschbaum, C.; Thomas, D. A.; Meijer, G.; von Helden, G.; Gilmore, K.; Seeberger, P. H.; Pagel, K. Remote Participation during Glycosylation Reactions of Galactose Building Blocks: Direct Evidence from Cryogenic Vibrational Spectroscopy. Angew. Chem., Int. Ed. 2020, 59, 6166–6171. https://doi.org/10.1002/anie.201916245
  • Fabijanczuk, K.; Gaspar, K.; Desai, N.; Lee, J.; Thomas, D. A.; Beauchamp, J. L.; Gao, J. Resin and Magnetic Nanoparticle-Based Free Radical Probes for Glycan Capture, Isolation, and Structural Characterization. Anal. Chem. 2019 91, 15837–15396. https://doi.org/10.1021/acs.analchem.9b01303
  • Thomas, D. A.; Mucha, E.; Lettow, M.; Meijer, G.; Rossi, M.; von Helden, G. Characterization of a trans–trans Carbonic Acid–Fluoride Complex by Infrared Action Spectroscopy in Helium Nanodroplets. J. Am. Chem. Soc. 2019 141, 5815–5823. http://dx.doi.org/10.1021/jacs.8b13542
  • Lettow, M.; Mucha, E.; Manz, C.; Thomas, D. A.; Marianski, M.; Meijer, G.; von Helden, G.; Pagel, K. The Role of the Mobile Proton in Fucose Migration. Anal. Bioanal. Chem. 2019, 411, 4637–4645. http://dx.doi.org/10.1007/s00216-019-01657-w
  • Marianski, M.; Seo, J.; Mucha, E.; Thomas, D. A.; Jung, S.; Schlögl, R.; Meijer, G.; Trunschke, A.; von Helden, G. Structural Characterization of Molybdenum Oxide Nanoclusters Using Ion Mobility Spectrometry–Mass Spectrometry and Infrared Action Spectroscopy. J. Phys. Chem. C 2019, 123, 7845–7853. http://dx.doi.org/10.1021/acs.jpcc.8b06985
  • Mucha, E.; Marianski, M.; Xu, F.-F.; Thomas, D. A.; Meijer, G..; von Helden, G.; Seeberger, P. H..; Pagel, K. Unraveling the Structure of Glycosyl Cations via Cold-Ion Infrared Spectroscopy. Nat. Commun. 2018, 9, 4174. http://dx.doi.org/10.1038/s41467-018-06764-3
  • Thomas, D. A.; Marianski, M.; Mucha, E.; Meijer, G.; Johnson, M. A.; von Helden, G. Ground-State Structure of the Proton-Bound Formate Dimer by Cold-ion Infrared Action Spectroscopy. Angew. Chem., Int. Ed. 2018, 57, 10615–10619. http://dx.doi.org/10.1002/anie.201805436
  • Mucha, E.; Lettow, M.; Marianski, M.; Thomas, D. A.; Struwe, W. B.; Harvey, D. J.; Meijer, G..; Seeberger, P. H.; von Helden, G.; Pagel, K. Fucose Migration in Intact Protonated Glycan Ions: A Universal Phenomenon in Mass Spectrometry. Angew. Chem., Int. Ed. 2018, 57, 7440–7443. http://dx.doi.org/10.1002/anie.201801418
  • Thomas, D. A.; Mucha, E.; Gewinner, S.; Schöllkopf, W; Meijer, G.; von Helden, G. Vibrational Spectroscopy of Fluoroformate, FCO2−, Trapped in Helium Nanodroplets. J. Phys. Chem. Lett. 2018, 9, 2305–2310. http://dx.doi.org/10.1021/acs.jpclett.8b00664
  • Mucha, E.; González Flórez, A. I.; Marianski, M.; Thomas, D. A.; Hoffmann, W.; Struwe, W. B.; Hahm, H. S.; Gewinner, S.; Schöllkopf, W.; Seeberger, P. H.; von Helden, G.; Pagel, K. Glycan Fingerprinting via Cold-Ion Infrared Spectroscopy. Angew. Chem., Int. Ed. 2017, 56, 11248–11251. http://dx.doi.org/10.1002/anie.201702896
  • Thomas, D. A.*; Coggon, M. M.*; Lignell, H.; Schilling, K. A.; Zhang, X.; Schwantes, R. H.; Flagan, R. C.; Seinfeld, J. H.; Beauchamp, J. L. Real-Time Studies of Iron Oxalate-Mediated Oxidation of Glycolaldehyde as a Model for Photochemical Aging of Aqueous Tropospheric Aerosols. Environ. Sci. Technol. 2016, 22, 12241–12249. http://dx.doi.org/10.1021/acs.est.6b03588 *Authors contributed equally
  • Desai, N.; Thomas, D. A.; Lee, J.; Gao, J.; Beauchamp, J. L. Eradicating Mass Spectrometric Glycan Rearrangement by Utilizing Free Radicals. Chem. Sci.  2016, 7, 5390-5397. http://dx.doi.org/10.1039/C6SC01371F
  • Sohn, C. H.; Gao, J.; Thomas, D. A.; Kim, T.-Y.; Goddard III, W. A.; Beauchamp, J. L. Mechanisms and Energetics of Free Radical Initiated Disulfide Bond Cleavage in Model Peptides and Insulin by Mass Spectrometry. Chem. Sci., 2015, 6, 4550-4560. http://dx.doi.org/10.1039/C5SC01305D
  • Thomas, D. A.; Wang, L.; Goh, B.; Kim, E. S.; Beauchamp, J.L. Mass Spectrometric Sampling of a Liquid Surface by Nanoliter Droplet Generation from Bursting Bubbles and Focused Acoustic Pulses: Application to Studies of Interfacial Chemistry. Anal. Chem. 2015, 87, 3336-3344. http://dx.doi.org/10.1021/ac504494t
  • Thomas, D. A.; Sohn, C. H.; Gao, J.; Beauchamp, J. L. Hydrogen Bonding Constrains Free Radical Reaction Dynamics at Serine and Threonine Residues in Peptides. J. Phys. Chem. A 2014, 118, 8380-8392. http://dx.doi.org/10.1021/jp501367w
  • Gao, J.; Thomas, D. A.; Sohn, C. H.; Beauchamp, J. L. Biomimetic Reagents for the Selective Free Radical and Acid–Base Chemistry of Glycans: Application to Glycan Structure Determination by Mass Spectrometry. J. Am. Chem. Soc. 2013, 135, 10684-10692. http://dx.doi.org/10.1021/ja402810t
  • Mui, W.; Thomas, D. A.; Downard, A. J.; Beauchamp, J. L.; Seinfeld, J. H.; Flagan, R. C. Ion Mobility-Mass Spectrometry with a Radial Opposed Migration Ion and Aerosol Classifier (ROMIAC). Anal. Chem.2013, 85, 6319-6326. http://dx.doi.org/10.1021/ac400580u