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Oleg Boyarkine

Cette personne a quitté l’EPFL

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Publications associées (73)

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Identification of Isomeric Biomolecules by Infrared Spectroscopy of Solvent-Tagged Ions

Oleg Boyarkine, Andrei Zviagin

The difference in functionality of many isomeric biomolecules requires their analytical identification for life science studies. We present a universal approach for quantitative identification of different small- to medium-sized isomeric biomolecules that ...

AMER CHEMICAL SOC2022

Effects of N-terminus substitution on the structure and spectroscopy of gas-phase helices

Thomas Rizzo, Oleg Boyarkine

Because of the importance of helices in the secondary structure of proteins, we have undertaken a study of their spectroscopy, fragmentation patterns and conformations in the gas phase. In this work, we describe the effects of substitution at the N-terminu ...

2008

Nonstatistical UV Fragmentation of Gas-Phase Peptides Reveals Conformers and Their Structural Features

Oleg Boyarkine, Vladimir Kopysov

Solving the 3D structure of a biomolecule requires recognition of its conformers and measurements of their individual structural identities, which can be compared with calculations. We employ the phenomenon of nonstatistical photofragmentation, detected by ...

Amer Chemical Soc2016

Salt Bridge Structure of Microhydrated Arginine Kinetically Trapped in the Gas Phase by Evaporative Cooling

Oleg Boyarkine, Andrei Zviagin

Aminoacids and peptides generally exhibit zwitterionic forms withsalt bridge (SB) structures in solution but charge-solvated (CS) motifsin the gas phase. Here, we report a study of non-covalent complexesof the protonated amino acid arginine, ArgH(+)(H2O)( ...

2023

UV Spectroscopic Studies of Cold Alkali Metal Ion–Crown Ether Complexes in the Gas Phase

Thomas Rizzo, Oleg Boyarkine, Yoshiya Inokuchi

We report UV photodissociation (UVPD) spectra of dibenzo-18-crown-6 (DB18C6) complexes with alkali metal ions (Li+, Na+, K+, Rb+, and Cs+) in a cold, 22-pole ion trap. All the complexes show a number of vibronically resolved bands, but the vibronic structu ...

American Chemical Society2011

A global line list for HDO between 0 and 35000 cm−1 constructed using multiphoton spectra

Oleg Boyarkine

Multiphoton spectroscopy of monodeuterated water is employed to determine more than 210 new energy levels of HDO in the 25 000–35 000 cm region. These new empirical energy levels are used to fit a potential energy surface (PES) valid between 20 000 cm and ...

2021

A direct measurement of the dissociation energy of water

Thomas Rizzo, Oleg Boyarkine, Pavlo Maksyutenko

We have performed a direct measurement of one of the most fundamental thermochemical values: the O-H bond energy in water. Using a triple-resonance laser excitation scheme, we excite the molecule through a series of vibrational overtone transitions to acce ...

2006

Identification of Isomeric Metabolites Using Cold Ion Spectroscopy Add-on to Orbitrap-Based Mass Spectrometer

Oleg Boyarkine, Vladimir Kopysov, Andrei Zviagin

The identification of chemical structures of metabolites available in trace-level quantities remains a challenging task in analytical chemistry. Although cold ion spectroscopy (CIS) has considerable potential to assist in such identification, the widesprea ...

American Chemical Society (ACS)2025

Spectroscopic probes of cold, gas-phase biomolecular ions: From amino acids to helical peptides

Thomas Rizzo, Oleg Boyarkine

2008

Identification of Isomeric Ephedrines by Cold Ion UV Spectroscopy: Toward Practical Implementation

Oleg Boyarkine, Vladimir Kopysov

Ephedrine and pseudoephedrine are stimulant drugs whose use is prohibited in athletic competition by the World Anti Doping Agency (WADA) at very different threshold doping violation concentrations. We use a recently developed universal approach that integr ...

2017

Isotopically selective collisional vibrational energy transfer in CF3H

Thomas Rizzo, Oleg Boyarkine

We investigate here the mechanism of collisionally-enhanced isotopic selectivity observed in infrared multiple photon dissociation (IRMPD) of vibrationally pre-excited CF3H by Boyarkin et al. (J. Chem. Phys. 118, 93 (2003)). For both the carbon-12 and carb ...

2007

Spectroscopic Evidence for Peptide-Bond-Selective Ultraviolet Photodissociation

Oleg Boyarkine, Vladimir Kopysov, Aleksandr Pereverzev

We study the photodissociation induced by ultraviolet excitation of amide bonds in gas-phase protonated peptides. Jointly, mass spectrometry and cold ion spectroscopy provide evidence for a selective non-statistical dissociation of specific peptide bonds i ...

2020

Ultraviolet Photodissociation of Peptides: New Insight on the Mobile Proton Model

Oleg Boyarkine, Aleksandr Pereverzev

In this work, we study the mechanism of peptide photodissociation by ultraviolet irradiation at 193 nm wavelength and discuss the role of ionization proton in this process. We found that substituting the ionization proton for the alkali metal cations (sodi ...

PLEIADES PUBLISHING INC2020

Interplay of Intra- and Intermolecular H-Bonding in a Progressively Solvated Macrocyclic Peptide

Thomas Rizzo, Oleg Boyarkine, Natalia Nagornova

Studying solvation of a large molecule on an atomic level is challenging because of the transient character and inhomogeneity of hydrogen bonding in liquid water. We studied water clusters of a protonated macrocyclic decapeptide, gramicidin S, which were p ...

American Association for the Advancement of Science2012

Cold ion spectroscopy for structural identifications of biomolecules

Oleg Boyarkine

Over the last decade, the spectroscopy of cryogenically cold ions iso- lated in the gas phase has been developed as a new tool for structural elucidations of biological molecules. Cooling allows for vibrational resolution in UV and IR spectra of small to m ...

2018

A new tandem mass spectrometer for photofragment spectroscopy of cold, gas-phase molecular ions

Thomas Rizzo, Oleg Boyarkine, Ulrich Lorenz, Annette Svendsen

We present here the design of a new tandem mass spectrometer that combines an electrospray ion source with a cryogenically cooled ion trap for spectroscopic studies of cold, gas-phase ions. The ability to generate large ions in the gas phase without fragme ...

American Institute of Physics2010

Assessing the performance of computational methods for the prediction of the ground state structure of a cyclic decapeptide

Ursula Röthlisberger, Ivano Tavernelli, Thomas Rizzo, Oleg Boyarkine, Natalia Nagornova, Manuel Dömer, Matteo Guglielmi

We benchmark the performance of various computational approaches, ranging from the classical nonpolarizable force fields AMBER FF96 and FF99SB, the polarizable force fields AMBER FF02polEP and AMOEBAbio09 to the semiempirical DFT method SCC-DFTB. The test ...

Wiley-Blackwell2013

Accurate bond dissociation energy of water determined by triple-resonance vibrational spectroscopy and ab initio calculations

Thomas Rizzo, Oleg Boyarkine, Pavlo Maksyutenko, Oleg Aseev

Triple-resonance vibrational spectroscopy is used to determine the lowest dissociation energy, D0, for the water isotopologue HD16O as 41 239.7 ± 0.2 cm−1 and to improve D0 for H216O to 41 145.92 ± 0.12 cm−1. Ab initio calculations including systematic bas ...

Elsevier2013

Conformational Structures of a Decapeptide Validated by First Principles Calculations and Cold Ion Spectroscopy

Thomas Rizzo, Oleg Boyarkine, Vladimir Kopysov, Natalia Nagornova

Calculated structures of the two most stable conformers of a protonated decapeptide gramicidin S in the gas phase have been validated by comparing the vibrational spectra, calculat- ed from first- principles and measured in a wide spectral range using infr ...

Wiley-V C H Verlag Gmbh2015

Conformational dependence of intramolecular vibrational redistribution in methanol

Thomas Rizzo, Oleg Boyarkine, Pavlo Maksyutenko

Previous state-selected spectra of methanol in the 5ν1 OH stretch overtone region [O. V. Boyarkin, T. R. Rizzo, and D. S. Perry, J. Chem. Phys. 110 (23), 11346 (1999)] revealed structure indicating intramolecular vibrational redistribution (IVR) on three t ...

2007