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European Journal of Mass Spectrometry

Patricia Wright, Hannah Britt, Cris Lapthorn, Christopher Whitmore
No abstract text is available yet for this article.
April 2018: European Journal of Mass Spectrometry
Medicharla V Jagannadham, D B Kameshwari, P Gayathri, R Nagaraj
A wide variety of post-translational modifications such as oxidation, phosphorylation, glycosylation, methylation, and acetylation play critical roles in cellular functions. Detection of post-translational modifications in proteins is important to understand their crucial roles in cellular functions. Identifying each modification requires special attention in mass spectral acquisition and analysis. Here, we report a mass spectral method for the detection of multiple phosphorylations in peptides by analyzing their products after fragmentation...
April 2018: European Journal of Mass Spectrometry
Diego D Colasurdo, Matías N Pila, Dacio A Iglesias, Sergio L Laurella, Danila L Ruiz
It has been demonstrated that uracil has a preponderant tautomeric form, but it is also known that different tautomers co-exist in this equilibrium. In this work, mass spectrometry is used as a helpful tool to analyse the equilibria, using derivative compounds to forbid the presence of some tautomers and ion trap mass spectrometry to follow relevant fragmentation pathways. Theoretical calculations were performed to confirm tautomers abundance by energy minimization in gas phase. Analysis of mass spectra of uracil, three methyl-substituted uracils, 2-thiouracil and three benzouracils suggest that uracil exists mainly as three tautomers in gas phase: one major structure that corresponds to the classical structure of uracil (pyrimidine-2,4(1H,3H)-dione) bearing two carbonyls and two NH moieties, and two minor enolic forms (4-hydroxypyrimidin-2(1H)-one and 2-hydroxypyrimidin-4(1H)-one)...
April 2018: European Journal of Mass Spectrometry
Yan Feng, Xiaoqiang Pei, Yongjun Cheng, Wenjun Sun, Gang Li, Yongjun Wang, Zhenhua Xi, Huzhong Zhang
In this paper, the effects of constant uniform magnetic fields on a miniature linear ion trap mass spectrometer with hyperbolic electrodes are simulated using SIMION 8.0 3D software. Magnetic fields in different directions have different effects on the trajectories of the trapped ions and the shape of the ion cloud. When the magnetic field is applied in the z-direction, namely the ion injection direction, the magnetic field will cause the ions focusing to the z-axis, and exert a compression effect on the ion cloud...
April 2018: European Journal of Mass Spectrometry
Stefanie Ickert, Johanna Hofmann, Jens Riedel, Sebastian Beck, Kevin Pagel, Michael W Linscheid
Mass spectrometry is applied as a tool for the elucidation of molecular structures. This premises that gas-phase structures reflect the original geometry of the analytes, while it requires a thorough understanding and investigation of the forces controlling and affecting the gas-phase structures. However, only little is known about conformational changes of oligonucleotides in the gas phase. In this study, a series of multiply charged DNA oligonucleotides (n = 15-40) has been subjected to a comprehensive tandem mass spectrometric study to unravel transitions between different ionic gas-phase structures...
April 2018: European Journal of Mass Spectrometry
Yue Li, Jianwen Yu, Zhiming Ruan, Chilai Chen, Ran Chen, Han Wang, Youjiang Liu, Xiaozhi Wang, Shan Li
In conventional high-field asymmetric waveform ion mobility spectrometry signal acquisition, multi-cycle detection is time consuming and limits somewhat the technique's scope for rapid field detection. In this study, a novel intelligent detection approach has been developed in which a threshold was set on the relative error of α parameters, which can eliminate unnecessary time spent on detection. In this method, two full-spectrum scans were made in advance to obtain the estimated compensation voltage at different dispersion voltages, resulting in a narrowing down of the whole scan area to just the peak area(s) of interest...
April 2018: European Journal of Mass Spectrometry
Meiru Guo, Detian Li, Yongjun Cheng, Yongjun Wang, Wenjun Sun, Xiaoqiang Pei, Meng Dong, Xuemin Sheng, Lan Zhao, Yanwu Li
With the rapid development of space technology in China, it is urgent to use mass spectrometer to detect the space environment. In this work, a space miniature magnetic sector mass spectrometer is evaluated, which consists of three subsystems: (1) physical unit, (2) electric control unit, (3) and high voltage power. It has 90° magnetic sector-field analyzer with double trajectory, in which a trajectory measurement range is from 1 to 12 amu, the other range is from 6 to 90 amu.The mass spectrometer has two work models, one is used to measure space neutral gas when the filament of mass spectrometer ion source turned on, the other is used to measure space charged ions when the filament turned off...
April 2018: European Journal of Mass Spectrometry
Patrick D Knight, Theodoros K Karamanos, Sheena E Radford, Alison E Ashcroft
Amyloid diseases represent a growing social and economic burden in the developed world. Understanding the assembly pathway and the inhibition of amyloid formation is key to developing therapies to treat these diseases. The neurodegenerative condition Machado-Joseph disease is characterised by the self-aggregation of the protein ataxin-3. Ataxin-3 consists of a globular N-terminal Josephin domain, which can aggregate into curvilinear protofibrils, and an unstructured, dynamically disordered C-terminal domain containing three ubiquitin interacting motifs separated by a polyglutamine stretch...
February 2018: European Journal of Mass Spectrometry
Alexander D Warren, David J Mitchell, Paul J Gates
There is still a need to develop reliable and robust matrix deposition methods for matrix-assisted laser desorption/ionisation mass spectrometry that are applicable to a range of matrices, solvents and analyte types. This paper presents a robust methodology for the airbrush application of matrices along with the implications of varying the set-up and airbrush parameters. A small number of organic analytes and metal salts are analysed in both positive and negative ion modes to exemplify this methodology. In the analyses with the airbrush deposited matrices, performance was enhanced when compared to standard pipette deposition with the need for a search for sweat spots greatly diminished due to the increase homogeneity of the matrix surface and resultant analyte spots...
February 2018: European Journal of Mass Spectrometry
Joakim S Jestilä, Einar Uggerud
Electrospray ionization of mixtures of succinic acid (here denoted H2 Su) and magnesium chloride in water/methanol give rise to ions of the type ESu- (E = H or ClMg). The unimolecular dissociation of these ions was studied by collisionally induced dissociation mass spectrometry and interpreted by quantum chemical calculations (density functional theory and the composite Gaussian-4 method) of relevant parts of the potential energy surfaces. The major dissociation pathways from HSu- were seen to be dehydration and decarboxylation, while ClMgSu- mainly undergoes decarboxylation...
February 2018: European Journal of Mass Spectrometry
George N Khairallah, Tom Waters, Anthony G Wedd, Richard Aj O'Hair
Two gas-phase catalytic cycles involving C-F bond activation of trifluoroethanol and trifluoroacetic acid were detected by multistage mass spectrometry experiments. A binuclear dimolybdate centre [Mo2 O6 (F)]- acts as the catalyst in each cycle. The first cycle, entered via the reaction of [Mo2 O6 (OH)]- with trifluoroethanol and elimination of water to form [Mo2 O6 (OCH2 CF3 )]- , proceeds via four steps: (1) oxidation of the alkoxo ligand and its elimination as aldehyde; (2) reaction of [Mo2 O5 (OH)]- with trifluoroethanol and elimination of water to form [Mo2 O5 (OCH2 CF3 )]; (3) decomposition of the alkoxo ligand via loss of 1,1 difluoroethene; and (4) reaction of [Mo2 O6 (F)]- with a second equivalent of trifluoroethanol to regenerate Mo2 O6 (OCH2 CF3 )]- ...
February 2018: European Journal of Mass Spectrometry
Jackie A Mosely, Peter Stokes, David Parker, Philip W Dyer, Antonis M Messinis
A novel method has been developed that enables chemical compounds to be transferred from an inert atmosphere glove box and into the atmospheric pressure ion source of a mass spectrometer whilst retaining a controlled chemical environment. This innovative method is simple and cheap to implement on some commercially available mass spectrometers. We have termed this approach inert atmospheric pressure solids analysis probe ( iASAP) and demonstrate the benefit of this methodology for two air-/moisture-sensitive chemical compounds whose characterisation by mass spectrometry is now possible and easily achieved...
February 2018: European Journal of Mass Spectrometry
Vladimir G Zaikin, Anton V Kozlov, Roman S Borisov, Igor Yu Shchapin
The influence of regio-isomerism of even-electron sulfonium ions on tandem electrospray and matrix-assisted laser desorption/ionization mass spectra recorded by using collision-induced dissociation was investigated. The initial organic sulfides belonged to isomeric thiabicyclane series (substituted 7- and 8-thiabicyclo[4.3.0]nonanes, 2- and 3-thiabicyclo[4.4.0]decanes) and phenylthiolanes. To investigate by the abovementioned mass spectrometry methods, the sulfides were preliminary S-alkylated by methyl, ethyl iodides, their deuterated analogs and trialkoxonium tetrafluoroborates to form corresponding sulfonium salts...
February 2018: European Journal of Mass Spectrometry
Bruno Figadére, Tangyuan Cao, Thomas H Morton
The Hofmann elimination of ammonium ions having a single positive charge is demonstrated to exhibit stereospecificity with regard to expulsion of neutral alkene. For the 3-hexyl series of threo and erythro 4-monodeuterated ions (3-hexylammonium ion; N,N,N-trimethyl- d3 -3-hexylammonium ion; N-ethyl-3-hexylammonium ion; N-methyl, N-ethyl-3-hexylammonium ion; N,N-dimethyl, N-ethyl-3-hexylammonium ion), the upper limit of the E:Z ratio of the expelled alkene (r) approaches 2 (the stereospecificity) with a deuterium isotope effect close to 2...
February 2018: European Journal of Mass Spectrometry
Isaac Agyekum, Lauren Pepi, Yanlei Yu, Junhui Li, Lufeng Yan, Robert J Linhardt, Shiguo Chen, I Jonathan Amster
Fucosylated chondroitin sulfates are complex polysaccharides extracted from sea cucumber. They have been extensively studied for their anticoagulant properties and have been implicated in other biological activities. While nuclear magnetic resonance spectroscopy has been used to extensively characterize fucosylated chondroitin sulfate oligomers, we herein report the first detailed mass characterization of fucosylated chondroitin sulfate using high-resolution Fourier transform ion cyclotron resonance mass spectrometry...
February 2018: European Journal of Mass Spectrometry
Wan Li, Xiangfeng Chen, Ze Wang, Yl Elaine Wong, Ri Wu, Y-L Winnie Hung, T-W Dominic Chan
Current imaging mass spectrometry techniques are faced with a major challenge related to ion suppression effect. Data regarding low-abundance components or low-polarity compounds cannot be normally obtained presumably because of the discrimination effect of easily ionized chemical components on desorption/ionization process. In this study, a new method was proposed to obtain images of chemical components in biological tissues or sections through in situ solid-phase extraction in sorbent mounted micro-funnel based spray ionization mass spectrometry...
February 2018: European Journal of Mass Spectrometry
Anton Skriba, Vladimir Havlicek
Compared with classical matrix-assisted laser-desorption ionization mass spectrometry (MALDI), the matrix free-based strategies generate a cleaner background, without significant noise or interference coming from an applied matrix, which is beneficial for the analysis of small molecules, such as drugs of abuse. In this work, we probed the detection efficiency of methamphetamine, heroin and cocaine in nanostructure-assisted laser desorption-ionization (NALDI) and desorption electrospray ionization and compared the sensitivity of these two matrix-free tools with a standard MALDI mass spectrometry experiment...
February 2018: European Journal of Mass Spectrometry
Bessem Brahim, Jean-Claude Tabet, Sandra Alves
Gas-phase fragmentation of single strand DNA-peptide noncovalent complexes is investigated in positive and negative electrospray ionization modes.Collision-induced dissociation experiments, performed on the positively charged noncovalent complex precursor ions, have confirmed the trend previously observed in negative ion mode, i.e. a high stability of noncovalent complexes containing very basic peptidic residues (i.e. R > K) and acidic nucleotide units (i.e. Thy units), certainly incoming from the existence of salt bridge interactions...
February 2018: European Journal of Mass Spectrometry
Stanislav Pekov, Maria Indeykina, Igor Popov, Alexey Kononikhin, Konstantin Bocharov, Sergey A Kozin, Alexander A Makarov, Eugene Nikolaev
It is known that aspartic acid isomerization process plays a role in aging processes and may be used as a marker for aging of natural materials. As for Alzheimer's disease, the most abundant modification in the peptide profile is the aspartate isomerization of amyloid-β. Liquid chromatography-electrospray ionization-mass spectrometry/mass spectrometry-based approaches with Collision Induced Dissociation (CID) or Electron Capture Dissociation (ECD) fragmentation provide a good and precise method for the relative quantitation of iso- to normal amyloid-β peptides but require additional time consuming steps...
February 2018: European Journal of Mass Spectrometry
Mario Thevis, Dietrich A Volmer
Selective androgen receptor modulators (SARMs) have been identified as a promising class of drug candidates potentially applicable to diverse pathological conditions commonly associated with significantly reduced muscle mass. Due to a suspected and meanwhile repeatedly proven misuse of SARMs in elite and amateur sport, sustaining constantly updated doping control analytical methods is critical for sports drug testing laboratories. These test methods predominantly utilize mass spectrometry-based instrumentations and, consequently, studies on the mass spectrometric behavior of new compounds and, where available, their metabolic products are vital for comprehensive doping controls...
February 2018: European Journal of Mass Spectrometry
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