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1. Ab initio investigations on the gas phase basicity and nonlinear optical properties of FLiₙOH species (n = 2–5)

Author:
Ambrish Kumar Srivastava; Neeraj Misra
Source:
RSC advances 2015 v.5 no.91 pp. 74206-74211
ISSN:
2046-2069
Subject:
alkalis; energy; gases; hydroxides; ionization; optical properties; salts; synthesis
Abstract:
... Superalkalies, due to lower ionization potentials than alkalies, possess potential reducing capability and can be used in the synthesis of a variety of charge transfer salts. In order to check whether superalkali hydroxides are as basic as a typical alkali hydroxide, we have performed a systematic investigation on the hydroxides of small FLiₙ (n = 2–5) superalkali clusters. The equilibrium structu ...
DOI:
10.1039/c5ra14735b

2. Analysis of a Common Cold Virus and Its Subviral Particles by Gas-Phase Electrophoretic Mobility Molecular Analysis and Native Mass Spectrometry

Author:
Weiss Victor U.; Bereszcazk Jessica Z.; Havlik Marlene; Kallinger Peter; Gösler Irene; Kumar Mohit; Blaas Dieter; Marchetti-Deschmann Martina; Heck Albert J. R.; Szymanski Wladyslaw W.; Allmaier Günter
Source:
Analytical chemistry 2015 v.87 no.17 pp. 8709-8717
ISSN:
1520-6882
Subject:
Human rhinovirus; capsid; common cold; desorption; electrophoresis; electrospraying; encapsulation; gases; genome; ionization; mass spectrometry; molecular weight; particle size; proteins; serotypes; virion; viruses
Abstract:
... Gas-phase electrophoretic mobility molecular analysis (GEMMA) separates nanometer-sized, single-charged particles according to their electrophoretic mobility (EM) diameter after transition to the gas-phase via a nano electrospray process. Electrospraying as a soft desorption/ionization technique preserves noncovalent biospecific interactions. GEMMA is therefore well suited for the analysis of inta ...
DOI:
10.1021/acs.analchem.5b01450
PubMed:
26221912
PubMed Central:
PMC4558612

3. Analytical capabilities of surface-assisted laser desorption/ionization in the determination of low-molecular-weight volatile compounds

Author:
A. A. Grechnikov
Source:
Journal of analytical chemistry 2015 v.70 no.9 pp. 1047-1054
ISSN:
1061-9348
Subject:
desorption; gases; ionization; ions; volatile compounds
Abstract:
... Main approaches to the determination of low-molecular-weight chemical compounds by surfaceassisted laser desorption/ionization (SALDI) are considered. Analytes are adsorbed from a gas phase on the surface of a specially prepared solid-state substrate. Then, the surface is exposed to pulse laser radiation, which leads to ionization and desorption of ions to be detected with a mass analyzer. The fac ...
DOI:
10.1134/S1061934815090051

4. Antioxidant Properties of Kanakugiol Revealed Through the Hydrogen Atom Transfer, Electron Transfer and M2+ (M2+ = Cu(II) or Co(II) Ion) Coordination Ability Mechanisms. A DFT Study In Vacuo and in Solution

Author:
Tshepiso J. Tsiepe; Mwadham M. Kabanda; Kemoabetswe R. N. Serobatse
Source:
Food biophysics 2015 v.10 no.3 pp. 342-359
ISSN:
1557-1858
Subject:
enthalpy; gases; cobalt; aqueous solutions; aromatic compounds; copper; ionization; acetonitrile; electron transfer; dissociation; hydrogen; hydrogen bonding; antioxidant activity; metal ions
Abstract:
... DFT studies on the conformational and antioxidant properties of kanakugiol were performed to investigate factors that contribute to its conformational preferences and to elucidate its antioxidant properties and mechanisms. The antioxidant activity has been considered through the ability of kanakugiol to scavenge free radical species and through its ability to chelate metal ions. The antiradical ac ...
DOI:
10.1007/s11483-015-9397-0

5. Clustering of sulfamic acid: ESI MS and theoretical study

Author:
M. Pszona; K. Haupa; A. Bil; K. Mierzwicki; Z. Szewczuk; Z. Mielke
Source:
Journal of mass spectrometry 2015 v.50 no.1 pp. 127-135
ISSN:
1076-5174
Subject:
acids; aerosols; ammonia; aqueous solutions; electrospray ionization mass spectrometry; gases; industry; ionization; spectrometers
Abstract:
... Sulfamic acid has wide application in industry and has been suggested to act as an effective nucleation agent for the formation of aerosols and cloud particles. From the point of view of the role that sulfamic acid may play in aerosol formation, the study of its homoaggregation is important. Gas phase clustering study was performed for sulfamic acid H₃N·SO₃, (ASA), from water and methanol–water so ...
DOI:
10.1002/jms.3505

6. Conformations of cationized linear oligosaccharides revealed by FTMS combined with in‐ESI H/D exchange

Author:
Yury Kostyukevich; Alexey Kononikhin; Igor Popov; Eugene Nikolaev
Source:
Journal of mass spectrometry 2015 v.50 no.10 pp. 1150-1156
ISSN:
1076-5174
Subject:
anions; cations; deuterium; gases; interphase; ionization; mass spectrometry; metal ions; oligosaccharides; pH; peptides; potassium; proteins; sodium; solvents; temperature
Abstract:
... Previously (Kostyukevich et al. Anal Chem 2014, 86, 2595), we have reported that oligosaccharides anions are produced in the electrospray in two different conformations, which differ by the rate of gas phase hydrogen/deuterium (H/D) exchange reaction. In the present paper, we apply the in‐electrospray ionization (ESI) source H/D exchange approach for the investigation of the oligosaccharides catio ...
DOI:
10.1002/jms.3633

7. Control of X-ray Induced Electron and Nuclear Dynamics in Ammonia and Glycine Aqueous Solution via Hydrogen Bonding

Author:
Unger Isaak; Hollas Daniel; Seidel Robert; Thürmer Stephan; Aziz Emad F.; Slavíček Petr; Winter Bernd
Source:
Journal of physical chemistry 2015 v.119 no.33 pp. 10750-10759
ISSN:
1520-5207
Subject:
X-radiation; ammonia; aqueous solutions; cations; gases; hydrogen bonding; ionization; isotopes; models; molecular dynamics; solutes; solvents; spectroscopy
Abstract:
... Recently, a new family of autoionization processes has been identified in aqueous phases. The processes are initiated by core-electron ionization of a solute molecule and involve proton transfer along the solute–solvent hydrogen bond. As a result, short-lived singly charged cations form with structures sharing a proton between solute and solvent molecules. These molecular transients decay by autoi ...
DOI:
10.1021/acs.jpcb.5b07283

8. Detection, Identification, and Occurrence of Thiotetronic Acids in Drinking Water from Underground Sources by Electrospray Ionization-High Field Asymmetric Waveform Ion Mobility Spectrometry-Quadrupole Time-of-Flight-Mass Spectrometry

Author:
Lyczko Jadwiga; Beach Daniel; Gabryelski Wojciech
Source:
Analytical chemistry 2015 v.87 no.19 pp. 9884-9891
ISSN:
1520-6882
Subject:
acids; aquifers; bacterial contamination; bottled water; disinfection; dissociation; drinking water; gases; groundwater; ionization; ions; mammals; organic compounds; ozonation; pharmaceutical industry; soil bacteria; tandem mass spectrometry; toxicity; water treatment; Canada; United States
Abstract:
... This paper demonstrates that electrospray ionization (ESI) with differential ion mobility spectroscopy (FAIMS) and “soft” mass spectrometry (MS) provide unique analytical capabilities that led to the discovery of sulfur-containing polar congeners of thiotetronic acid (TA) in drinking water from underground sources in Canada and the United States. Polar TAs accumulate in underground aquifers and ap ...
DOI:
10.1021/acs.analchem.5b02372

9. Diastereoselective synthesis of tetraalkyl (R,R)-1,2-cyclohexylene-diamino-di-phosphonates bearing thiophene, furan and pyrrole moieties. Computational and experimental study on their formation

Author:
Anna Chrostowska; Clovis Darrigan; Said Khayar; Patrick Baylère; Jarosław Lewkowski; Anna Krzyczmonik; Paweł Tokarz; Katarzyna Ślepokura; Tadeusz Lis
Source:
Tetrahedron 2015 v.71 pp. 2561-2571
ISSN:
0040-4020
Subject:
X-radiation; chemical structure; energy; gases; ionization; spectroscopy; stereochemistry; thiophene
Abstract:
... Diastereoselective additions of dialkyl phosphites to three diimines bearing DACH moiety and thiophene, furan or pyrrole rings were studied in the aspect of their stereochemistry, structure of predominant products and mechanism. For these reasons, analysis of reaction mixture, X-ray studies of products, UV-photoelectron spectroscopy and ionization energies of the starting imines were performed exp ...
DOI:
10.1016/j.tet.2015.03.010

10. Direct Ion Imaging Approach for Investigation of Ion Dynamics in Multipole Ion Guides

Author:
Syed Sarfaraz U. A. H.; Maher Simon; Eijkel Gert B.; Ellis Shane R.; Jjunju Fred; Taylor Stephen; Heeren Ron M. A.
Source:
Analytical chemistry 2015 v.87 no.7 pp. 3714-3720
ISSN:
1520-6882
Subject:
computer software; cooling; electrodes; gases; image analysis; ionization; ions; mathematical models; radio waves; spectrometers
Abstract:
... A key requirement of electrospray ionization (ESI) and other techniques facilitating ionization at elevated pressures is the efficient transport of free gas-phase ions into the high vacuum region of the mass spectrometer. Radio frequency (RF) multipole ion guides that allow for collisional cooling are one of the most popular means of achieving this. However, their performance is highly dependent o ...
DOI:
10.1021/ac5041764

11. Direct Ionization of Solid-Phase Microextraction Fibers for Quantitative Drug Bioanalysis: From Peripheral Circulation to Mass Spectrometry Detection

Author:
Ahmad Sheelan; Tucker Michael; Spooner Neil; Murnane Darragh; Gerhard Ute
Source:
Analytical chemistry 2015 v.87 no.1 pp. 754-759
ISSN:
1520-6882
Subject:
blood sampling; cost effectiveness; drugs; food analysis; gases; ionization; ions; liquid chromatography; propranolol; solid phase microextraction; solvents; tandem mass spectrometry; washing
Abstract:
... A novel approach is described for the quantitative bioanalysis of drugs in blood samples by ionization of the analytes collected on solid-phase microextraction (SPME) fibers by mass spectrometry (MS). The technique combines the attractive features of SPME microsampling using minimal sample volumes with the speed, selectivity, and sensitivity capabilities of MS detection. The method reported in thi ...
DOI:
10.1021/ac503706n

12. Direct Quantification of Chemical Warfare Agents and Related Compounds at Low ppt Levels: Comparing Active Capillary Dielectric Barrier Discharge Plasma Ionization and Secondary Electrospray Ionization Mass Spectrometry

Author:
Wolf Jan-Christoph; Schaer Martin; Siegenthaler Peter; Zenobi Renato
Source:
Analytical chemistry 2015 v.87 no.1 pp. 723-729
ISSN:
1520-6882
Subject:
detection limit; electrospray ionization mass spectrometry; evaporation; gases; hydrolysis; ionization; monitoring; nerve agents; toxicity
Abstract:
... A novel active capillary dielectric barrier discharge plasma ionization (DBDI) technique for mass spectrometry is applied to the direct detection of 13 chemical warfare related compounds, including sarin, and compared to secondary electrospray ionization (SESI) in terms of selectivity and sensitivity. The investigated compounds include an intact chemical warfare agent and structurally related mole ...
DOI:
10.1021/ac5035874

13. Electrical breakdown in tissue electroporation

Author:
Enric Guenther; Nina Klein; Paul Mikus; Michael K. Stehling; Boris Rubinsky
Source:
Biochemical and biophysical research communications 2015 v.467 pp. 736-741
ISSN:
0006-291X
Subject:
cell membranes; electric field; electrodes; electrolysis; electroporation; experimental design; gases; genes; ionization; magnetic resonance imaging; medicine; transfection; ultrasonics
Abstract:
... Electroporation, the permeabilization of the cell membrane by brief, high electric fields, has become an important technology in medicine for diverse application ranging from gene transfection to tissue ablation. There is ample anecdotal evidence that the clinical application of electroporation is often associated with loud sounds and extremely high currents that exceed the devices design limit af ...
DOI:
10.1016/j.bbrc.2015.10.072

14. Enhancing MSn mass spectrometry strategy for carbohydrate analysis: A b2 ion spectral library

Author:
Jun Xue; Roger A. Laine; Khushi L. Matta
Source:
Journal of proteomics 2015 v.112 pp. 224-249
ISSN:
1874-3919
Subject:
branching; energy; gases; glycosidic linkages; glycosyltransferases; ionization; ions; isomers; ligands; mass spectrometry; neoplasms; polysaccharides; protein conformation; proteome; receptors; spectrometers; trisaccharides
Abstract:
... Searchable mass spectral libraries for glycans may be enhanced using a B2 ion library. Using a quadrupole ion-trap mass spectrometer, successive fragmentations of sodiated oligosaccharides were carried out in the positive ion mode. In B,Y-type fragmentation, disaccharide B2 ions are generated which correspond to specific glycosidic linkages using progressive MS stages. Fragmentation of “B2 ions” c ...
DOI:
10.1016/j.jprot.2014.07.013

15. Ensemble Methods Enable a New Definition for the Solution to Gas-Phase Transfer of Intrinsically Disordered Proteins

Author:
Borysik Antoni J.; Kovacs Denes; Guharoy Mainak; Tompa Peter
Source:
Journal of the American Chemical Society 2015 v.137 no.43 pp. 13807-13817
ISSN:
1520-5126
Subject:
gases; ionization; mass spectrometry; proteins; solvents
Abstract:
... Intrinsically disordered proteins (IDPs) are important for health and disease, yet their lack of net structure precludes an understanding of their function using classical methods. Gas-phase techniques provide a promising alternative to access information on the structure and dynamics of IDPs, but the fidelity to which these methods reflect the solution conformations of these proteins has been dif ...
DOI:
10.1021/jacs.5b06027

16. Evidence for an Unrecognized Secondary Anthropogenic Source of Organosulfates and Sulfonates: Gas-Phase Oxidation of Polycyclic Aromatic Hydrocarbons in the Presence of Sulfate Aerosol

Author:
Riva Matthieu; Tomaz Sophie; Cui Tianqu; Lin Ying-Hsuan; Perraudin Emilie; Gold Avram; Stone Elizabeth A.; Villenave Eric; Surratt Jason D.
Source:
Environmental Science & Technology 2015 v.49 no.11 pp. 6654-6664
ISSN:
1520-5851
Subject:
acidity; aerosols; anthropogenic activities; gases; ionization; mass spectrometry; naphthalene; photooxidation; polycyclic aromatic hydrocarbons; relative humidity; sulfates; sulfonates; tracer techniques; ultra-performance liquid chromatography; Pakistan; United States
Abstract:
... In the present study, formation of aromatic organosulfates (OSs) from the photo-oxidation of polycyclic aromatic hydrocarbons (PAHs) was investigated. Naphthalene (NAP) and 2-methylnaphthalene (2-MeNAP), two of the most abundant gas-phase PAHs and thought to represent “missing” sources of urban SOA, were photochemically oxidized in an outdoor smog chamber facility in the presence of nonacidified a ...
DOI:
10.1021/acs.est.5b00836

17. An Experimental and Computational Study of the Gas-Phase Acidities of the Common Amino Acid Amides

Author:
Plummer Chelsea E.; Stover Michele L.; Bokatzian Samantha S.; Davis John T. M.; Dixon David A.; Cassady Carolyn J.
Source:
Journal of physical chemistry 2015 v.119 no.30 pp. 9661-9669
ISSN:
1520-5207
Subject:
amides; aspartic acid; cysteine; energy; gases; glutamic acid; histidine; ionization; ions; models; nitrogen; peptides; physical chemistry; proteins; spectrometers; tryptophan; tyrosine
Abstract:
... Using proton-transfer reactions in a Fourier transform ion cyclotron resonance mass spectrometer and correlated molecular orbital theory at the G3(MP2) level, gas-phase acidities (GAs) and the associated structures for amides corresponding to the common amino acids have been determined for the first time. These values are important because amino acid amides are models for residues in peptides and ...
DOI:
10.1021/acs.jpcb.5b04486

18. Exploring the Aqueous Vertical Ionization of Organic Molecules by Molecular Simulation and Liquid Microjet Photoelectron Spectroscopy

Author:
Tentscher Peter R.; Seidel Robert; Winter Bernd; Guerard Jennifer J.; Arey J. Samuel
Source:
Journal of physical chemistry 2015 v.119 no.1 pp. 238-256
ISSN:
1520-5207
Subject:
alcohols; aniline; cations; chemical elements; dimethyl sulfide; energy; gases; hydrogen bonding; ionization; molecular conformation; molecular dynamics; oxidation; solutes; solvents; spectroscopy; thymidine
Abstract:
... To study the influence of aqueous solvent on the electronic energy levels of dissolved organic molecules, we conducted liquid microjet photoelectron spectroscopy (PES) measurements of the aqueous vertical ionization energies (VIEₐq) of aniline (7.49 eV), veratrole alcohol (7.68 eV), and imidazole (8.51 eV). We also reanalyzed previously reported experimental PES data for phenol, phenolate, thymidi ...
DOI:
10.1021/jp508053m

19. Exploring the Conformational Variability in the Heme b Propionic Acid Side Chains through the Effect of a Biological Probe: A Study of the Isolated Ions

Author:
De Petris Alberto; Chiavarino Barbara; Crestoni Maria Elisa; Coletti Cecilia; Re Nazzareno; Fornarini Simonetta
Source:
Journal of physical chemistry 2015 v.119 no.5 pp. 1919-1929
ISSN:
1520-5207
Subject:
dissociation; environmental factors; gases; heme; hydrogen bonding; ionization; ions; iron; ligands; photons; propionic acid; protoporphyrin; solvents; spectroscopy; temperature; thermodynamics
Abstract:
... The iron(III) protoporphyrin IX complex with imidazole, a biologically relevant ligand, occupying an axial position, has been studied by infrared multiple photon dissociation (IRMPD) spectroscopy. The complex has been delivered in gas-phase by electrospray ionization (ESI), mass selected in an ion trap, and assayed by IRMPD spectroscopy in two complementary frequency regions. The fingerprint range ...
DOI:
10.1021/jp5113476

20. From Solution to Gas Phase: The Implications of Intramolecular Interactions on the Evaporative Dynamics of Substance P During Electrospray Ionization

Author:
Servage Kelly A.; Silveira Joshua A.; Fort Kyle L.; Russell David H.
Source:
Journal of physical chemistry 2015 v.119 no.13 pp. 4693-4698
ISSN:
1520-5207
Subject:
evaporation; gases; glutamine; heat; ionization; ions; molecular dynamics; mutation; phenylalanine; protons; spectroscopy; substance P
Abstract:
... Substance P (RPKPQQFFGLM-NH₂) [M + 3H]³⁺ ions have been shown to occupy two distinct conformer states, a compact population of conformers that is formed by evaporation of hydrated ions, and an elongated population of conformers that is formed by collisional heating of the compact conformer. Molecular dynamics (MD) simulations and amino acid mutations revealed that the compact conformer is stabiliz ...
DOI:
10.1021/jp512708u

21. Gas Phase Uranyl Activation: Formation of a Uranium Nitrosyl Complex from Uranyl Azide

Author:
Gong Yu; de Jong Wibe A.; Gibson John K.
Source:
Journal of the American Chemical Society 2015 v.137 no.18 pp. 5911-5915
ISSN:
1520-5126
Subject:
chlorine; dissociation; endothermy; energy; gases; ionization; ligands; methodology; nitrogen; oxidation; spectrometers; uranium
Abstract:
... Activation of the oxo bond of uranyl, UO₂²⁺, was achieved by collision induced dissociation (CID) of UO₂(N₃)Cl₂– in a quadrupole ion trap mass spectrometer. The gas phase complex UO₂(N₃)Cl₂– was produced by electrospray ionization of solutions of UO₂Cl₂ and NaN₃. CID of UO₂(N₃)Cl₂– resulted in the loss of N₂ to form UO(NO)Cl₂–, in which the “inert” uranyl oxo bond has been activated. Formation of ...
DOI:
10.1021/jacs.5b02420

22. Gas phase ion chemistry of an ion mobility spectrometry based explosive trace detector elucidated by tandem mass spectrometry

Author:
Joseph Kozole; Lauren A. Levine; Jill Tomlinson-Phillips; Jason R. Stairs
Source:
Talanta 2015 v.140 pp. 10-19
ISSN:
0039-9140
Subject:
ammonia; ammonium nitrate; atmospheric pressure; detectors; explosives; gases; ionization; ions; isotope labeling; methylene chloride; nitrogen dioxide; spectrometers; tandem mass spectrometry; trinitrotoluene
Abstract:
... The gas phase ion chemistry for an ion mobility spectrometer (IMS) based explosive detector has been elucidated using tandem mass spectrometry. The IMS system, which is operated with hexachloroethane and isobutyramide reagent gases and an ion shutter type gating scheme, is connected to the atmospheric pressure interface of a triple quadrupole mass spectrometer (MS/MS). Product ion masses, daughter ...
DOI:
10.1016/j.talanta.2015.03.001

23. Gas-Phase Acidities of Phosphorylated Amino Acids

Author:
Stover Michele L.; Plummer Chelsea E.; Miller Sean R.; Cassady Carolyn J.; Dixon David A.
Source:
Journal of physical chemistry 2015 v.119 no.46 pp. 14604-14621
ISSN:
1520-5207
Subject:
amides; amino acids; anions; energy; gases; ionization; phosphates; physical chemistry; solvents; spectrometers; temperature
Abstract:
... Gas-phase acidities and heats of formation have been predicted at the G3(MP2)/SCRF-COSMO level of theory for 10 phosphorylated amino acids and their corresponding amides, including phospho-serine (pSer), -threonine (pThr), and -tyrosine (pTyr), providing the first reliable set of these values. The gas-phase acidities (GAs) of the three named phosphorylated amino acids and their amides have been de ...
DOI:
10.1021/acs.jpcb.5b08616

24. Gas-Phase Chemical Separation of Phosphatidylcholine and Phosphatidylethanolamine Cations via Charge Inversion Ion/Ion Chemistry

Author:
Rojas-Betancourt Stella; Stutzman John R.; Londry Frank A.; Blanksby Stephen J.; McLuckey Scott A.
Source:
Analytical chemistry 2015 v.87 no.22 pp. 11255-11262
ISSN:
1520-6882
Subject:
anions; cations; dissociation; fatty acids; gases; ionization; phosphatidylcholines; phosphatidylethanolamines; separation
Abstract:
... The [M + H]⁺ cations formed upon electrospray ionization of the glycerophospholipids phosphatidylcholine (PC) and phosphatidylethanolamine (PE) show distinct reactivities upon gas-phase reactions with doubly deprotonated 1,4-phenylenedipropionic acid (PDPA). PC cations undergo charge inversion via adduct formation with subsequent methyl cation and proton transfer to the acid to yield [PC – CH₃]⁻ a ...
DOI:
10.1021/acs.analchem.5b02243
PubMed:
26477819
PubMed Central:
PMC5068822

25. Gas-Phase Conformations and Energetics of Protonated 2′-Deoxyadenosine and Adenosine: IRMPD Action Spectroscopy and Theoretical Studies

Author:
Wu R. R.; Yang Bo; Berden G.; Oomens J.; Rodgers M. T.
Source:
Journal of physical chemistry 2015 v.119 no.7 pp. 2795-2805
ISSN:
1520-5207
Subject:
RNA; adenosine; dissociation; gases; hydrogen bonding; ionization; photons; spectroscopy
Abstract:
... The gas-phase conformations of protonated 2′-deoxyadenosine, [dAdo+H]⁺, and its RNA analogue protonated adenosine, [Ado+H]⁺, generated upon electrospray ionization are examined using infrared multiple photon dissociation (IRMPD) action spectroscopy techniques and supported by complementary theoretical electronic structure calculations. IRMPD action spectra are measured over the IR fingerprint regi ...
DOI:
10.1021/jp509267k

26. Gas-Phase FRET Efficiency Measurements To Probe the Conformation of Mass-Selected Proteins

Author:
Czar Martin F.; Zosel Franziska; König Iwo; Nettels Daniel; Wunderlich Bengt; Schuler Benjamin; Zarrine-Afsar Arash; Jockusch Rebecca A.
Source:
Analytical chemistry 2015 v.87 no.15 pp. 7559-7565
ISSN:
1520-6882
Subject:
chemical analysis; electrospray ionization mass spectrometry; energy transfer; fluorescence; fluorescence emission spectroscopy; gases; ionization; mutants; pH; proteins; spectrometers
Abstract:
... Electrospray ionization and mass spectrometry have revolutionized the chemical analysis of biological molecules, including proteins. However, the correspondence between a protein’s native structure and its structure in the mass spectrometer (where it is gaseous) remains unclear. Here, we show that fluorescence (Förster) resonance energy transfer (FRET) measurements combined with mass spectrometry ...
DOI:
10.1021/acs.analchem.5b01591

27. High-Throughput Characterization of Small and Large Molecules Using Only a Matrix and the Vacuum of a Mass Spectrometer

Author:
Woodall Daniel W.; Wang Beixi; Inutan Ellen D.; Narayan Srinivas B.; Trimpin Sarah
Source:
Analytical chemistry 2015 v.87 no.9 pp. 4667-4674
ISSN:
1520-6882
Subject:
crystals; drugs; gases; humans; ionization; ions; metabolites; nylon; peptides; proteins; spectrometers; tandem mass spectrometry; urine
Abstract:
... Matrix assisted ionization vacuum (MAIV) rapidly generates gas-phase analyte ions from subliming solid-phase matrix:analyte crystals for analysis by mass spectrometry (MS). Ionization from the solid-phase allows the use of a variety of surfaces for introducing matrix:analyte samples to the vacuum of a mass spectrometer, including common laboratory materials, such as disposable pipet tips, filter p ...
DOI:
10.1021/ac504475x

28. Hypervalent radical formation probed by electron transfer dissociation of zwitterionic tryptophan and tryptophan‐containing dipeptides complexed with Ca2+ and 18‐crown‐6 in the gas phase

Author:
Akimasa Fujihara; Sou Matsuo; Michiko Tajiri; Yoshinao Wada; Shigeo Hayakawa
Source:
Journal of mass spectrometry 2015 v.50 no.10 pp. 1124-1129
ISSN:
1076-5174
Subject:
ammonia; calcium; chemical bonding; dipeptides; dissociation; electron transfer; gases; hydrogen; ionization; mass spectrometry; spectrometers; tryptophan; zwitterions
Abstract:
... The relationship between peptide structure and electron transfer dissociation (ETD) is important for structural analysis by mass spectrometry. In the present study, the formation, structure and reactivity of the reaction intermediate in the ETD process were examined using a quadrupole ion trap mass spectrometer equipped with an electrospray ionization source. ETD product ions of zwitterionic trypt ...
DOI:
10.1002/jms.3628

29. Hyphenation of Thermal Analysis to Ultrahigh-Resolution Mass Spectrometry (Fourier Transform Ion Cyclotron Resonance Mass Spectrometry) Using Atmospheric Pressure Chemical Ionization For Studying Composition and Thermal Degradation of Complex Materials

Author:
Rüger Christopher P.; Miersch Toni; Schwemer Theo; Sklorz Martin; Zimmermann Ralf
Source:
Analytical chemistry 2015 v.87 no.13 pp. 6493-6499
ISSN:
1520-6882
Subject:
Betula; Fagus; Picea; abietic acid; aldehydes; alkanes; atmospheric pressure; biomass; elemental composition; fuel oils; gases; ionization; lignocellulose; mass spectrometry; pellets; petroleum; polar compounds; pyrolysis; softwood; spectrometers; temperature; thermal analysis; thermal properties
Abstract:
... In this study, the hyphenation of a thermobalance to an ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometer (UHR FTICR MS) is presented. Atmospheric pressure chemical ionization (APCI) is used for efficient ionization. The evolved gas analysis (EGA), using high-resolution mass spectrometry allows the time-resolved molecular characterization of thermally induced process ...
DOI:
10.1021/acs.analchem.5b00785

30. Identification and separation of saxitoxins using hydrophilic interaction liquid chromatography coupled to traveling wave ion mobility‐mass spectrometry

Author:
Salomé Poyer; Corinne Loutelier‐Bourhis; Gaël Coadou; Florence Mondeguer; Julien Enche; Anne Bossée; Philipp Hess; Carlos Afonso
Source:
Journal of mass spectrometry 2015 v.50 no.1 pp. 175-181
ISSN:
1076-5174
Subject:
gases; gonyautoxins; hydrophilic interaction chromatography; ionization; isomers; mass spectrometry; saxitoxins
Abstract:
... The aim of this work was to develop a reliable and efficient analytical method to characterise and differentiate saxitoxin analogues (STX), including sulphated (gonyautoxins, GTX) and non‐sulphated analogues. For this purpose, hydrophilic interaction liquid chromatography (HILIC) was used to separate sulphated analogues. We also resorted to ion mobility spectrometry to differentiate the STX analog ...
DOI:
10.1002/jms.3515

31. In ESI‐source H/D exchange under atmospheric pressure for peptides and proteins of different molecular weights from 1 to 66 kDa: the role of the temperature of the desolvating capillary on H/D exchange

Author:
Yury Kostyukevich; Alexey Kononikhin; Igor Popov; Alexander Spasskiy; Eugene Nikolaev
Source:
Journal of mass spectrometry 2015 v.50 no.1 pp. 49-55
ISSN:
1076-5174
Subject:
atmospheric pressure; deuterium; deuterium oxide; gases; ionization; ions; magnetic materials; mass spectrometry; molecular weight; peptides; proteins; temperature
Abstract:
... Transition of proteins from the solution to the gas phase during electrospray ionization remains a challenging problem despite the large amount of attention it has received during the past few decades. One of the major questions relates to the extent to which proteins in the gas phase retain their condensed phase structures. We have used in‐electrospray source hydrogen/deuterium exchange to determ ...
DOI:
10.1002/jms.3535

32. Influence of carrier gas on microwave-induced pyrolysis

Author:
D. Beneroso; J.M. Bermúdez; A. Arenillas; J.A. Menéndez
Source:
Journal of analytical and applied pyrolysis 2015 v.113 pp. 153-157
ISSN:
0165-2370
Subject:
carbon monoxide; gases; hydrogen; ionization; microwave treatment; pyrolysis
Abstract:
... Interest in microwave-induced pyrolysis has increased in recent years due to its several advantages over conventional pyrolysis. Most of these advantages are related to the presence of microplasmas in microwave heating, since the pyrolysis reactions that take place in a plasma atmosphere generally produce light molecules, such as H2 and CO. Although the exact nature of these plasmas is as yet unkn ...
DOI:
10.1016/j.jaap.2014.12.005

33. Ionization-based detectors for gas chromatography

Author:
Colin F. Poole
Source:
Journal of chromatography 2015 v.1421 pp. 137-153
ISSN:
0021-9673
Subject:
combustion; detectors; electrons; flame ionization; gases; helium; hydrogen; ionization; mass spectrometry; photons
Abstract:
... The gas phase ionization detectors are the most widely used detectors for gas chromatography. The column and makeup gases commonly used in gas chromatography are near perfect insulators. This facilitates the detection of a minute number of charge carriers facilitating the use of ionization mechanisms of low efficiency while providing high sensitivity. The main ionization mechanism discussed in thi ...
DOI:
10.1016/j.chroma.2015.02.061

34. Mass Spectrometry and Nuclear Magnetic Resonance Spectroscopy Study of Carbohydrate Decomposition by Hydrothermal Liquefaction Treatment: A Modeling Approach on Bio-oil Production from Organic Wastes

Author:
Croce Annamaria; Battistel Ezio; Chiaberge Stefano; Spera Silvia; Reale Samantha; De Angelis Francesco
Source:
Energy & Fuels 2015 v.29 no.9 pp. 5847-5856
ISSN:
1520-5029
Subject:
atmospheric pressure; biofuels; cellulose; decarboxylation; furfural; gas chromatography-mass spectrometry; gases; glucose; ionization; liquefaction; models; nuclear magnetic resonance spectroscopy; organic wastes; oxidation; polymerization; stable isotopes
Abstract:
... Glucose and cellulose as model compounds were treated under hydrothermal liquefaction (HTL) conditions to describe the main reaction pathways that are involved in the process. The HTL-derived phases (gas phase, bio-oil, aqueous phase, and solid residue) were fully characterized by a combination of analytical techniques [i.e., elemental analysis (EA), gas chromatography–mass spectrometry (GC–MS), e ...
DOI:
10.1021/acs.energyfuels.5b01204

35. Mass spectrometric methods to analyze the structural organization of macromolecular complexes

Author:
Khadijeh Rajabi; Alison E. Ashcroft; Sheena E. Radford
Source:
Methods 2015 v.89 pp. 13-21
ISSN:
1046-2023
Subject:
biochemical compounds; crosslinking; deuterium; electrospray ionization mass spectrometry; gases; hydroxyl radicals; ionization
Abstract:
... With the development of soft ionization techniques such as electrospray ionization (ESI), mass spectrometry (MS) has found widespread application in structural biology. The ability to transfer large biomolecular complexes intact into the gas-phase, combined with the low sample consumption and high sensitivity of MS, has made ESI-MS a method of choice for the characterization of macromolecules. Thi ...
DOI:
10.1016/j.ymeth.2015.03.004

36. Miniature Flow-Through Low-Temperature Plasma Ionization Source for Ambient Ionization of Gases and Aerosols

Author:
Spencer Sandra E.; Santiago Brandon G.; Glish Gary L.
Source:
Analytical chemistry 2015 v.87 no.23 pp. 11887-11892
ISSN:
1520-6882
Subject:
aerosols; caffeine; cellulose; gases; ionization; ions; pyrolysis
Abstract:
... The design and operation of an inexpensive, miniature low-temperature plasma ion source is detailed. The miniature low-temperature plasma ion source is operated in a “flow-through” configuration, wherein the gaseous or aerosolized analyte, caffeine or pyrolyzed ethyl cellulose, in a carrier gas is used as the plasma gas. In this flow-through configuration, the sensitivity for the caffeine standard ...
DOI:
10.1021/acs.analchem.5b03447

37. N3 and O2 Protonated Tautomeric Conformations of 2′-Deoxycytidine and Cytidine Coexist in the Gas Phase

Author:
Wu R. R.; Yang Bo; Frieler C. E.; Berden G.; Oomens J.; Rodgers M. T.
Source:
Journal of physical chemistry 2015 v.119 no.18 pp. 5773-5784
ISSN:
1520-5207
Subject:
absorption; complement; cytidine; dissociation; gases; ionization; least squares; oxygen; photons
Abstract:
... Infrared multiple photon dissociation action spectra of the protonated forms of the cytidyl nucleosides, 2′-deoxycytidine, [dCyd+H]⁺, and cytidine, [Cyd+H]⁺, are acquired over the IR fingerprint and hydrogen-stretching regions. Electronic structure calculations are performed at the B3LYP/6-311+G(d,p) level to determine the stable low-energy tautomeric conformations of these species generated upon ...
DOI:
10.1021/jp5130316

38. Negative electrospray ionization mode in mass spectrometry: A new perspective via modeling

Author:
Christos I. Gioumouxouzis; Maria G. Kouskoura; Catherine K. Markopoulou
Source:
Journal of Chromatography B 2015 v.998-999 pp. 97-105
ISSN:
1570-0232
Subject:
water solubility; gases; surface tension; ions; ionization; models; least squares; chromatography; computer software; mass spectrometry; adverse effects
Abstract:
... Electrospray ionization technique is used for production of gas phase ions without fragmentation and is considered as one of the most sensitive analytical methods for structural characterization of molecules. Nonetheless, the determination of some parameters (physicochemical properties or structural features) that may enhance the signal response especially in the negative ion mode has not yet been ...
DOI:
10.1016/j.jchromb.2015.06.009

39. Oxidation Dynamics of Methionine with Singlet Oxygen: Effects of Methionine Ionization and Microsolvation

Author:
Liu Fangwei; Liu Jianbo
Source:
Journal of physical chemistry 2015 v.119 no.25 pp. 8001-8012
ISSN:
1520-5207
Subject:
energy; gases; hydrogen peroxide; hydroperoxides; ionization; mass spectrometry; methionine; models; oxidation; oxygen; physical chemistry; singlet oxygen
Abstract:
... We report an in-depth study on the gas-phase reactions of singlet O₂[a¹Δg] with methionine (Met) at different ionization and hydration states (including deprotonated [Met – H]⁻, hydrated deprotonated [Met – H]⁻(H₂O)₁,₂, and hydrated protonated MetH⁺(H₂O)₁,₂), using guided-ion-beam scattering mass spectrometry. The measurements include the effects of collision energy (Ecₒₗ) on reaction cross sectio ...
DOI:
10.1021/acs.jpcb.5b03779

40. Oxidation of Gas-Phase SO2 on the Surfaces of Acidic Microdroplets: Implications for Sulfate and Sulfate Radical Anion Formation in the Atmospheric Liquid Phase

Author:
Hung Hui-Ming; Hoffmann Michael R.
Source:
Environmental Science & Technology 2015 v.49 no.23 pp. 13768-13776
ISSN:
1520-5851
Subject:
sulfur dioxide; gases; sulfites; sulfates; atmospheric chemistry; hydrogen peroxide; ionization; spectrometers; models; aerosols; electron transfer; superoxide anion; oxidants; pH; oxidation; cities; droplets; oxygen; China
Abstract:
... The oxidation of SO₂(g) on the interfacial layers of microdroplet surfaces was investigated using a spray-chamber reactor coupled to an electrospray ionization mass spectrometer. Four major ions, HSO₃–, SO₃•–, SO₄•– and HSO₄–, were observed as the SO₂(g)/N₂(g) gas-mixture was passed through a suspended microdroplet flow, where the residence time in the dynamic reaction zone was limited to a few hu ...
DOI:
10.1021/acs.est.5b01658

41. Photocatalytic activity of electrophoretically deposited (EPD) TiO2 coatings

Author:
Manuel Nuño; Richard J. Ball; Chris R. Bowen; Rajnish Kurchania; G. D. Sharma
Source:
Journal of materials science 2015 v.50 no.14 pp. 4822-4835
ISSN:
0022-2461
Subject:
gases; X-ray diffraction; titanium; coatings; pollution control; ionization; nanomaterials; titanium dioxide; glass; isopropyl alcohol; scanning electron microscopy; wavelengths; nitrogen dioxide; stainless steel; mass spectrometry; electrophoresis; air pollution; photocatalysts; Raman spectroscopy
Abstract:
... This paper describes the application of electrophoretic deposition for air pollution removal using anatase as a photoactive coating. In this study, the anatase form of TiO₂has been applied to (1) fluorine-doped tin oxide (FTO)-coated glass; (2) 304L stainless steel; and (3) titanium substrates using isopropanol and acetylacetone-based solutions at 20, 40, 60 and 80 V. In order to increase the stre ...
DOI:
10.1007/s10853-015-9022-0

42. Photoluminescence Spectroscopy of Mass-Selected Electrosprayed Ions Embedded in Cryogenic Rare-Gas Matrixes

Author:
Kern Bastian; Greisch Jean-François; Strelnikov Dmitry; Weis Patrick; Böttcher Artur; Ruben Mario; Schäfer Bernhard; Schooss Detlef; Kappes Manfred M.
Source:
Analytical chemistry 2015 v.87 no.23 pp. 11901-11906
ISSN:
1520-6882
Subject:
cations; dissociation; gases; ionization; neon; neutralization; photoluminescence; spectroscopy; synthesis
Abstract:
... An apparatus is presented which combines nanoelectrospray ionization for isolation of large molecular ions from solution, mass-to-charge ratio selection in gas-phase, low-energy-ion-beam deposition into a (co-condensed) inert gas matrix and UV laser-induced visible-region photoluminescence (PL) of the matrix isolated ions. Performance is tested by depositing three different types of lanthanoid dik ...
DOI:
10.1021/acs.analchem.5b03491

43. Photosynthesis of a Combinatorial Peptide Library in the Gas Phase

Author:
Lee Sunyoung; Glover Matthew S.; Reilly James P.; Clemmer David E.
Source:
Analytical chemistry 2015 v.87 no.18 pp. 9384-9388
ISSN:
1520-6882
Subject:
dissociation; gases; ionization; peptide libraries; photosynthesis; spectrometers
Abstract:
... A strategy for generating large numbers of peptides from a relatively small number of precursors based on photosynthetic combination in the gas phase is presented. In this approach, electrospray ionization is used to create a combination of proton-bound dimers from a specified set of peptides present in solution. The dimers are then accumulated and isolated in an ion trap mass spectrometer. Photoe ...
DOI:
10.1021/acs.analchem.5b02179

44. Protomers of Benzocaine: Solvent and Permittivity Dependence

Author:
Warnke Stephan; Seo Jongcheol; Boschmans Jasper; Sobott Frank; Scrivens James H.; Bleiholder Christian; Bowers Michael T.; Gewinner Sandy; Schöllkopf Wieland; Pagel Kevin; von Helden Gert
Source:
Journal of the American Chemical Society 2015 v.137 no.12 pp. 4236-4242
ISSN:
1520-5126
Subject:
benzocaine; electrical properties; gases; ionization; local anesthetics; protein subunits; solvents; spectroscopy
Abstract:
... The immediate environment of a molecule can have a profound influence on its properties. Benzocaine, the ethyl ester of para-aminobenzoic acid that finds an application as a local anesthetic, is found to adopt in its protonated form at least two populations of distinct structures in the gas phase, and their relative intensities strongly depend on the properties of the solvent used in the electrosp ...
DOI:
10.1021/jacs.5b01338

45. Radical scavenging activity characterization of synthetic isochroman-derivatives of hydroxytyrosol: A gas-phase DFT approach

Author:
Nikolaos Nenadis; Dimitrios Siskos
Source:
Food research international 2015 v.76 pp. 506-510
ISSN:
0963-9969
Subject:
catechol; cations; dissociation; electron transfer; energy transfer; enthalpy; free radical scavengers; free radicals; gases; hydrogen; ionization; oxygen radical absorbance capacity; prediction
Abstract:
... Hydroxytyrosol (HT) and a set of synthetic isochroman derivatives of HT have been studied with regards to their radical scavenging activity in the gas employing density functional theory (DFT) and the Becke's 3 Lee Yang Parr (B3LYP) functional. Values of molecular descriptors (bond dissociation enthalpy, BDE; ionization potential, IP; proton dissociation enthalpy, PDE; proton affinity, PA; electro ...
DOI:
10.1016/j.foodres.2015.06.040

46. Release of Native-like Gaseous Proteins from Electrospray Droplets via the Charged Residue Mechanism: Insights from Molecular Dynamics Simulations

Author:
McAllister Robert G.; Metwally Haidy; Sun Yu; Konermann Lars
Source:
Journal of the American Chemical Society 2015 v.137 no.39 pp. 12667-12676
ISSN:
1520-5126
Subject:
droplets; evaporation; gases; ionization; ions; models; molecular dynamics; proteins; shrinkage; sodium; solvents
Abstract:
... The mechanism whereby gaseous protein ions are released from charged solvent droplets during electrospray ionization (ESI) remains a matter of debate. Also, it is unclear to what extent electrosprayed proteins retain their solution structure. Molecular dynamics (MD) simulations offer insights into the temporal evolution of protein systems. Surprisingly, there have been no all-atom simulations of t ...
DOI:
10.1021/jacs.5b07913

47. Structural characterization of major soyasaponins in traditional cultivars of Fagioli di Sarconi beans investigated by high-resolution tandem mass spectrometry

Author:
Giuliana Bianco; Alessandro Buchicchio; Tommaso R. I. Cataldi
Source:
Analytical and bioanalytical chemistry 2015 v.407 no.21 pp. 6381-6389
ISSN:
1618-2642
Subject:
European Union; Phaseolus vulgaris; beans; carbon dioxide; cultivars; dissociation; ecotypes; gases; ionization; ions; irradiation; protected designation of origin; reversed-phase high performance liquid chromatography; reversed-phase liquid chromatography; saponins; spectrometers; sugars; tandem mass spectrometry; wavelengths; Italy
Abstract:
... Major soyasaponins, i.e., soyasaponins I, V, βg, and αg from traditional Fagioli di Sarconi beans (Phaseolus vulgaris L., ecotype Tabacchino), were analyzed by reversed-phase liquid chromatography–mass spectrometry (MS) using high-resolution Fourier transform ion cyclotron resonance (FTICR) MS on electrospray ionization in positive-ion mode. Fagioli di Sarconi beans are protected by the European U ...
DOI:
10.1007/s00216-015-8810-3

48. Study on the accelerated Gutknecht self-cyclocondensation of amino-sugars under atmospheric pressure chemical ionization conditions

Author:
Hao-Yang Wang; Jun-Ting Zhang; Shi-Hao Sun; Shu-Sheng Zhang; Fang Zhang; Hui Zhu; Yin-Long Guo
Source:
RSC advances 2015 v.5 no.127 pp. 105079-105083
ISSN:
2046-2069
Subject:
atmospheric pressure; gases; glucosamine; ionization; mass spectrometry
Abstract:
... An unexpected gas phase Gutknecht self-condensation of d-glucosamine hydrochloride to 2,5-deoxyfructosazine (2,5-DOF) in atmospheric pressure chemical ionization mass spectrometry (APCI-MS) was described. Mechanistic studies indicated that the thermospray conditions in APCI largely accelerate the irreversible Gutknecht self-cyclocondensation reaction of amino-sugars. Our observations provide a pro ...
DOI:
10.1039/c5ra22331h

49. Synthesis of refractory organic matter in the ionized gas phase of the solar nebula

Author:
Maïa Kuga; Bernard Marty; Yves Marrocchi; Laurent Tissandier
Source:
Proceedings of the National Academy of Sciences of the United States of America 2015 v.112 no.23 pp. 7129-7134
ISSN:
0027-8424
Subject:
carbon; gases; ionization; nitrogen; noble gases; organic matter; temperature
Abstract:
... In the nascent solar system, primitive organic matter was a major contributor of volatile elements to planetary bodies, and could have played a key role in the development of the biosphere. However, the origin of primitive organics is poorly understood. Most scenarios advocate cold synthesis in the interstellar medium or in the outer solar system. Here, we report the synthesis of solid organics un ...
DOI:
10.1073/pnas.1502796112
PubMed:
26039983
PubMed Central:
PMC4466694

50. Theoretical study on the structural and antioxidant properties of some recently synthesised 2,4,5-trimethoxy chalcones

Author:
Guirong Wang; Yunsheng Xue; Lin An; Youguang Zheng; Yunyan Dou; Ling Zhang; Yi Liu
Source:
Food chemistry 2015 v.171 pp. 89-97
ISSN:
0308-8146
Subject:
antioxidant activity; benzene; chalcones; chemical bonding; dissociation; electron transfer; enthalpy; free radical scavengers; gases; hydrogen; ionization; solvents
Abstract:
... The free radical scavenging activity of a series of 2,4,5-trimethoxy chalcones has been computationally explored using the density functional theory (DFT) method. Three potential working mechanisms, hydrogen atom transfer (HAT), stepwise electron transfer proton transfer (SET-PT) and sequential proton loss electron transfer (SPLET) have been investigated. The physiochemical parameters including O– ...
DOI:
10.1016/j.foodchem.2014.08.106