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European Journal of Mass Spectrometry

Peter J Derrick, Jürgen Grotemeyer
No abstract text is available yet for this article.
2016: European Journal of Mass Spectrometry
Dmitry I Zhilyaev, Roman S Borisov, Nikolai Yu Polovkov, Vladimir G Zaikin
Reaction with α,ω-N,N-dimethylaminoalkylamines (2-dimethylaminoethylamine, 3- dimethylaminopropylamine, 4-dimethylaminobutylamine) to form Schiff bases followed by quaternization of the N,N-dimethylamino group by alkyl (deuteroalkyl) halides to generate fixed-charge fragments is suggested for the characterization of carbonyl compounds by matrix-assisted laser desorption ionization (MALDI) mass spectrometry. As model objects, some aliphatic aldehydes and alicyclic and steroid ketones were involved in the modification...
2016: European Journal of Mass Spectrometry
Hsin-Wen Tien, Yu-Meng Ou, Ren-Yu Hsu, Tsung-Shing Wang, Guor-Rong Her
The trimethylsilyl (TMS) derivative is one of the most widely utilized derivatives for analyzing polar compounds by gas chromatography. An ion two mass units higher than the protonated molecular ion was observed in analyzing TMS-monocarboxylic acids by using gas chromatography electrospray ionization mass spectrometry (GC-ESI/MS). The structure of the M + 2 compound was investigated using tandem mass spectrometry and high-resolution mass spectrometry. The results suggest that one methyl group bound to the silicon atom was replaced by a hydroxyl group during the ESI process...
2016: European Journal of Mass Spectrometry
Elizaveta A Sysoeva, Alexander A Sysoev
The new ion-optical system of the laser time-of-flight (TOF) mass spectrometer on the basis of two tandem wedge-shape reflectors has been offered and implemented. A new method of correcting chromatic aberration by the ion energy was proposed that used a wire electrode unit with adjustable potentials. This unit allows one to adjust the local TOF of the ions in a narrow energy range ± (1-2)% within the total ion packet with an energy spread of ± 20%. The method reduces the duration of the ion packets by up to 1...
2016: European Journal of Mass Spectrometry
Li Zhou, Jiao Qian, Jianxu Liu, Ruimin Zhao, Bowei Li, Rui Wang
Amyloid-βdegrading enzyme neprilysin (NEP) plays a pivotal role in eliminating Aβ The oxidized modification of NEP by 4-hydroxy-2-nonenal (HNE) may reduce the clearance of Aβ in cultured cells and Alzheimer's disease (AD) brains. The aim of this research is to study whether HNE could modify the NEP protein and identify the specific sites of HNE-NEP modification using a linear trap quadrapole (LTQ) Velos Pro-Orbitrap Elite mass spectrometer. NEP activity was determined after SH-SY5Y cells had incubated with HNE (20 μM) for 24 hours...
2016: European Journal of Mass Spectrometry
Shanshan Wang, Guohua Zhu, Mengmeng Chen, Jinsong Liu, Kezhi Jiang
p-Chloroaniline is one of the banned aromatic amines in azo dyes, but it is very difficult to distinguish it from its isomers due to their identical retention time in chromatography and similar mass spectra. In this work, derivatization of the isomeric chloroanilines was carried out to yield the corresponding N-tosyl chloroanilines, which were completely separated by gas chromatography and also possessed clearly different electron ionization mass spectra. Thus, the three isomers could be differentiated and determined at the same time...
2016: European Journal of Mass Spectrometry
Vtaliy Chagovets, Aleksey Kononikhin, Nataliia Starodubtseva, Yury Kostyukevich, Igor Popov, Vladimir Frankevich, Eugene Nikolaev
The importance of high-resolution mass spectrometry for the correct data interpretation of a direct tissue analysis is demonstrated with an example of its clinical application for an endometriosis study. Multivariate analysis of the data discovers lipid species differentially expressed in different tissues under investigation. High-resolution mass spectrometry allows unambiguous separation of peaks with close masses that correspond to proton and sodium adducts of phosphatidylcholines and to phosphatidylcholines differing in double bond number...
2016: European Journal of Mass Spectrometry
Nikolai V Konenkov, Eugenii Ya Chernyak, Vladimir A Stepanov
Dipole resonant excitation of ions creates instability bands which follow iso-β lines where β is the characteristic exponent (stability parameter). Instability bands are exited most effectively on the fundamental frequency π= βΩ/2. Here π is the angle resonance frequency of the dipolar voltage applied to x or y pair rods of the analyzer, and Ω is the angle frequency of the main drive voltage. Our goal is to study the mass peak shape in the third stability region with dipolar resonance excitation of the instability band with respect to the resonance frequency π and the dipolar potential amplitude...
2016: European Journal of Mass Spectrometry
Andreas Bierstedt, Jens Riedel
A novel direct sampling ionisation scheme for ambient mass spectrometry is presented. Desorption and ionisation are achieved by a quasi-continuous laser induced plasma in air. Since there are no solid or liquid electrodes involved the ion source does not suffer from chemical interferences or fatigue originating from erosive burning or from electrode consumption. The overall plasma maintains electro-neutrality, minimising charge effects and accompanying long term drift of the charged particles trajectories. In the airborne plasma approach the ambient air not only serves as the plasma medium but at the same time also slows down the nascent ions via collisional cooling...
2016: European Journal of Mass Spectrometry
Catalina-Ionica Ciobanu, Raluca Stefanescu, Marius Niculaua, Teodora Teslaru, Robert Gradinaru, Gabi Drochioiu
The NAP peptide (H(2)N-(1)NAPVSIPQ(8)-CONH(2)) is a truncated version of the activity-dependent neuroprotective protein. Its neuroprotective activities consist of the inhibition of Aβ(25-35) and Aβ(1-40) fibrillogenesis as well as protection against Aβ-induced neurotoxicity and prevention of microtubule disruption associated with Alzheimer's disease. Therefore, we synthesized NAP and its mutant peptide with the sequence: H(2)N-(1)NAPVCIPQ(8)-COOH (NAPCOH), by replacing serine S(5) with cysteine C(5). Both native and mutant peptides were further used to study their interaction with iron ions...
2016: European Journal of Mass Spectrometry
Yury Kostyukevich, Alexander Zherebker, Alexey Kononikhin, Maria Indeykina, Igor Popov, Eugene Nikolaev
We report the investigation of the collision-induced dissociation (CID) and electron-capture dissociation (ECD) product fragmentations of the supermetallized complexes of Substance P and several monovalent metals. The supermetallization is the phenomenon of the formation of the complex ion peptide-metals in the gas phase when the peptide accepts an unexpectedly large number of metals. We have obtained and investigated complexes with the incorporation of up to four cesium (Cs), up to five potassium (K) and up to six silver (Ag) atoms...
2016: European Journal of Mass Spectrometry
Yasushi Shigeri, Takuya Kamimura, Masanori Ando, Koichi Uegaki, Hiroaki Sato, Fumito Tani, Ryuichi Arakawa, Tomoya Kinumi
The sensitivity, range of applications, and reaction mechanism of 2-hydrazinoquinoline as a reactive matrix for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) were examined. Using a reaction chamber (125L) equipped with a stirring fan and a window for moving the MALDI-MS plate and volatile samples in and out, the sensitivities of 2-hydrazinoquinoline to gaseous aldehydes (formaldehyde, acetaldehyde, propionaldehyde, and n-butyraldehyde) and ketones (acetone, methyl ethyl ketone, and methyl isobutyl ketone) were determined to be at least parts per million (ppm) levels...
2016: European Journal of Mass Spectrometry
Marco Roverso, Maura Brioschi, Cristina Banfi, Silvia Visentin, Silvia Burlina, Roberta Seraglia, Pietro Traldi, Annunziata Lapolla
Gestational diabetes (GDM) is the most common complication of pregnancy and it is associated with maternal and fetal short- and long-term consequences. GDM modifies placental structure and function, but many of the underlying mechanisms are still unclear. The aim of this study is to develop and compare two different methods, based respectively on gel-based and gel-free proteomics, in order to investigate the placental proteome in the absence or in the presence of GDM and to identify, through a comparative approach, possible changes in protein expression due to the GDM condition...
2016: European Journal of Mass Spectrometry
Nick A van Huizen, Theo M Luider, Karl J Jobst, Johan K Terlouw, John L Holmes, Peter C Burgers
Relative affinity measurements of monovalent metal ions (= Li(+), Cu(+) and Ag(+)) towards aliphatic amines, alcohols and methyl alkanoates (P) have been performed using the kinetic method on the dissociation of metal bound dimer ions of the type P(1)-M(+)-P(2). It was found that the cations' affinity towards long chain (≥C(4) chain length) n- and s-alkylamines, n-alkanols and methyl n- alkanoates was unexpectedly enhanced. This is attributed to a bidentate interaction of the metal ion with the amine, alcohol or ester functional group and the aliphatic chain, paralleling earlier observations on metal bound nitriles...
2016: European Journal of Mass Spectrometry
Andreas Lagojda, Dirk Kuehne, Oliver Krug, Andreas Thomas, Tina Wigger, Uwe Karst, Wilhelm Schänzer, Mario Thevis
Research into developing anabolic agents for various therapeutic purposes has been pursued for decades. As the clinical utility of anabolic-androgenic steroids has been found to be limited because of their lack of tissue selectivity and associated off-target effects, alternative drug entities have been designed and are commonly referred to as selective androgen receptor modulators (SARMs). While most of these SARMs are of nonsteroidal structure, the drug candidate MK-0773 comprises a 4-aza-steroidal nucleus...
2016: European Journal of Mass Spectrometry
Jürgen H Gross
Of the ionic liquid 1-butyl-3-methylimidazolium (C(+)) tricyanomethide (A(-)) high-mass cluster ions of both positive ([C(n)A(n-1)](+)) and negative ([C(n-1)A(n)](-)) charge were generated and detected by direct analysis in real time (DART) Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry (MS). After optimization of the settings of the DART ionization source and of the mass analyzer ions of m/z values unprecedented in DART-MS were detected. Thus, the upper m/z limits of positive-ion and negative-ion DART- MS were substantially expanded...
2016: European Journal of Mass Spectrometry
Yury Kostyukevich, Alexey Kononikhin, Eugene Kukaev, Jentaie Shiea, Igor Popov, Eugene Nikolaev
Supermetallization is the recently observed phenomenon of the formation of complex ions of peptide-metal in the gas phase when the peptide accepts an unexpectedly large number of metal atoms. It has been found that supermetallization takes place during electrospray ionization when charged droplets are evaporating at relatively high temperature (ca 400°C). In the present paper, we demonstrate supermetallized complexes of small protein ubiquitin and two peptides with Th(IV). We have observed complexes of ubiquitin with up to five thorium atoms, and attaching each Th(IV) requires the removal of four hydrogen atoms...
2016: European Journal of Mass Spectrometry
Jing Zhou, Xin-Yu Bian, Lei Zhou, Serge Maurice Mbadinga, Shi-Zhong Yang, Jin-Feng Liu, Ji-Dong Gu, Bo-Zhong Mu
Metabolite profiling is a powerful method in research on anaerobic biodegradation of hydrocarbons. Hydroxylation and carboxylation are proposed pathways in anaerobic degradation but very little direct evidence is available about metabolites and signature biomarkers. 2-Acetylalkanoic acid is a potential signature metabolite because of its unique and specific structure among possible intermediates. A procedure for the synthesis of four homologues with various carbon chain lengths was proposed and the characteristics of 2-acetyl- alkanoic acid esters were investigated using four derivatization processes, namely methyl, ethyl, n-butyl and trimethylsilyl esterification...
2016: European Journal of Mass Spectrometry
Hang Wang, Jiaojian Yuan
Mass spectrometry has been applied to the targeted analysis of commonly used additives (such as Irganox 1010, Irganox 1076, Irgafos 168, etc.) in plastic materials, but a fast and straightforward method for the non-targeted identification and quantification of unusual or potentially new antioxidant additives is still unavailable. In this study, a novel and simple method for the identification and quantification of unknown antioxidant additives in plastic food packaging using ultrasonic extraction and ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry has been developed...
2016: European Journal of Mass Spectrometry
Anna Smolira, Stanisław Hałas
As a natural antibacterial peptide, lysozyme (LZ) is widely used in medicine and the food industry. Despite many years of research on this compound, its new antibacterial properties are still to be determined. The primary aim of this work is to demonstrate the application of the matrix-assisted laser desorption ionization (MALDI) time-of-flight mass spectrometric analysis of LZ directly in hen egg white samples without extraction thereof. The egg white samples were kept over 10 weeks at room temperature and measured every week...
2016: European Journal of Mass Spectrometry
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