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John R. Eyler
co -Principal Investigator
   



Professor Emeritus, Courtesy Professor,
and Adjunct Assistant-In Chemistry
Department of Chemistry
University of Florida
eylerjr@chem.ufl.edu
   
MSPIRE Research Interests

The MSPIRE research in John Eyler’s group uses tunable infrared lasers to obtain spectra of gaseous ions, with an emphasis on using these spectra to differentiate isomers of mono- and oligosaccharides. Tunable CO2 and optical parametric oscillator (OPO) lasers are employed for experiments at the University of Florida, and work in The Netherlands is conducted at the free electron laser for infrared experiments (FELIX) facility at the FOM Institute ”Rijnhuizen.” In this work the infrared multiple photon dissociation (IRMPD) action spectra of gaseous ions of interest are obtained. In addition, theoretical electronic structure calculations are used to model the ionic systems of interest and to aid in interpreting the measured IRMPD spectra. Systems studied to date include many different monosaccharides, often locked into one specific anomeric structure by O-methylation, and a number of glucose-containing disaccharides with different linkage positions and anomericity. In addition, studies which determine the structures of oxocarbenium ions that may be important intermediates in glycoconjugate transformations and dimeric species of small moelcules (dopamine, guanine) found in various metabolic pathways are ongoing in collaborations with professors at UF.

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Figure. Theoretical infrared spectra calculated for the lowest energy cyclic form (a) and the open-chain form (b) of D-glucose anions with charge locations indicated for each structure, compared to the experimental spectrum obtained at the FELIX facility.

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MSPIRE Publications

1.Differentiation of Methyl-glucopyranoside Anomers by Infrared Multiple Photon Dissociation with a Tunable CO2 Laser, S. E. Stefan and J. R. EylerAnal. Chem. 2009, 81(3), 1224-1227.

2. Infrared Multiphoton Dissociation Spectroscopy of Ions in Penning Traps, J. R. Eyler, Mass. Spectrom. Rev. 2009, 28(3), 448-467.

3. Triuret as a Potential Hypokalemic Agent: Structure Characterization of Triuret and Triuret-alkali Metal Adducts by Mass Spectrometric Techniques,, S.P. Palii, C.S. Contreras, J.D. Steill, S. Palii, J. Oomens, and J.R. Eyler, Arch. Biochem. Biophys.2010, 498(1), 23-34.

4. Differentiation of Glucose-containing Disaccharides by Infrared Multiple Photon Dissociation with a Tunable CO2 Laser and Fourier Transform Ion Cyclotron Resonance Mass Spectrometry S.E. Stefan and J.R. Eyler, Int. J. Mass Spectrom. 2010, 297, 96-101.

5. Hydrogen/Deuterium Exchange of Phenylalanine Analogs Studied with Infrared Multiple Photon Dissociation, , C.S. Contreras, N.C. Polfer, A.C. Chung, J. Oomens, and J.R. Eyler, Int. J. Mass Spectrom. 2010, 297, 162-169 (Special Issue on Ion Spectroscopy).

6. Structural Elucidation of Direct Analysis in Real Time-Ionized Nerve Agent Simulants with Infrared Multiple Photon Dissociation Spectroscopy, J.L. Rummel, J.D. Steill, J. Oomens, C.S. Contreras, W.L. Pearson, J. Szczepanski, D.H. Powell, and J.R. Eyler, Anal. Chem., 2011, 83, 4045-4052.


7. Assignment of the Stereochemistry and Anomeric Configuration of Structurally Informative Product Ions Derived from Disaccharides: Infrared Photodissociation of Glycosyl-glycolaldehydes in the Negative Ion Mode,, B. Bendiak, D. Brown, T. Fang, S. Stefan, J. Eyler, L. Pearson, and N. Polfer, Carbohydrate Research, 2010, 345, 2390-2400.

8. Vibrational Signatures of Zwitterionic and Charge-Solvated Structures for Alkaline Earth-Tryptophan Dimer Complexes in the Gas Phase, W. K. Mino Jr., J. Szczepanski, W. L. Pearson, D. H. Powell, R. C. Dunbar, J. R. Eyler, N. C. Polfer, Int. J. Mass Spectrom., 2010, 297, 131-138.

9. Direct Evidence for Ring Opening of Monosaccharide Anions in the Gas Phase: Photodissociation of Aldohexoses and Aldohexoses Derived from Disaccharides Using Variable-Wavelength Infrared Irradiation in the Carbonyl Stretch Region,, D. J. Brown, S. E. Stefan, G. Berden, J. D. Steill, J. Oomens, J. R. Eyler, and B. Bendiak, Carbohydrate Research, 2011, submitted.

10. Differentiation of Closely Related Isomers: Application of Data Mining Techniques in Conjunction with Variable Wavelength Infrared Multiple Photon Dissociation Mass Spectrometry for Identification of Glucose-containing Disaccharide Ions, , S. E. Stefan, M. Ehsan, W. L. Pearson, A. Aksenov, V. Boginski, B. Bendiak and J. R. Eyler, Anal. Chem., 2011, submitted.






























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