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European Journal of Mass Spectrometry

Tomasz Grześkowiak, Agnieszka Zgoła-Grześkowiak, Danuta Rusińska-Roszak, Iwona Zaporowska-Stachowiak, Magdalena Jeszka-Skowron
The results of research on selected drugs used in palliative care are presented, including fentanyl, tramadol, metoclopramide, hyoscine butylbromide, midazolam, haloperidol, levomepromazine and clonazepam. Interpretation of their ESI mass spectra obtained by the use of a triple quadrupole linear ion trap mass spectrometer is given. As a result, fragmentation pathways described in the literature are complemented and presented with more details. On their basis, transitions for quantitative analysis are selected and chromatographic conditions for the determination of the palliative care drugs are proposed as well...
November 6, 2018: European Journal of Mass Spectrometry
Alexander Kassler, Ernst Pittenauer, Nicole Doerr, Guenter Allmaier
The understanding of ageing mechanisms of antioxidants in base oils is indispensable for the development of improved lubricants. In this study, a novel artificial ageing method based on the application of peroxide as oxidant is presented for improved monitoring of thermo-oxidative degradation processes in combination with mass spectrometry. Model oils containing aminic and phenolic antioxidants were aged and chemical structures of their oxidation products were elucidated by ultrahigh performance liquid chromatography and electrospray ionization high resolution (Orbitrap) mass spectrometry...
November 6, 2018: European Journal of Mass Spectrometry
Jérémie Giorgetti, Antony Lechner, Elise Del Nero, Alain Beck, Yannis-Nicolas François, Emmanuelle Leize-Wagner
Capillary electrophoresis-mass spectrometry coupling is a growing technique in biopharmaceutics characterization. Assessment of monoclonal antibodies is well known at middle-up and bottom-up levels to obtain information about the sequence, post-translational modifications and degradation products. Intact protein analysis is an actual challenge to be closer to the real protein structure. At this level, actual techniques are time consuming or cumbersome processes. In this work, a 20 minutes separation method has been developed to optimize characterization of intact monoclonal antibodies...
October 23, 2018: European Journal of Mass Spectrometry
Estelle Rathahao-Paris, Sandra Alves, Nawel Boussaid, Nicole Picard-Hagen, Véronique Gayrard, Pierre-Louis Toutain, Jean-Claude Tabet, Douglas N Rutledge, Alain Paris
Direct injection-mass spectrometry can be used to perform high-throughput metabolomic fingerprinting. This work aims to evaluate a global analytical workflow in terms of sample preparation (urine sample dilution), high-resolution detection (quality of generated data based on criteria such as mass measurement accuracy and detection sensitivity) and data analysis using dedicated bioinformatics tools. Investigation was performed on a large number of biological samples collected from sheep infected or not with scrapie...
October 18, 2018: European Journal of Mass Spectrometry
T Sony, L Sridhar, L Sai Sachin, Vvs Lakshmi, S Prabhakar
N-Alkylaminoethanols, N,N'-dialkylaminoethanols, and triethanolamine are the hydrolyzed products or precursors of V-agents/nitrogen mustards. These compounds are prone to undergo oxidation in environmental matrices. Detection of the oxidized products provides a clue for the presence of parent amine compounds and it is an important task in the verification process of chemical weapons convention. Gas chromatography/mass spectrometry is the technique of choice for the detection of most of the chemical warfare agents; however, it is ideal to develop gas chromatography/mass spectrometry techniques for all the possible degradation products of chemical warfare agents as well...
October 9, 2018: European Journal of Mass Spectrometry
Jakob Heller, Milan Ončák, Nina K Bersenkowitsch, Christian van der Linde, Martin K Beyer
Charged cesium iodide clusters doped with mono-, di- and triglycine serve as a model system for sea salt aerosols containing biological molecules. Here, we investigate reactions of these complexes under infrared irradiation, with spectra obtained by infrared multiple photon dissociation. The cluster ions are generated via electrospray ionization and analyzed in the cell of a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer. Depending on the cluster size and peptide length, loss of HI or loss of a glycine unit is observed...
October 4, 2018: European Journal of Mass Spectrometry
Andrii Piatkivskyi, Justin Kai-Chi Lau, Giel Berden, Jos Oomens, Alan C Hopkinson, Kw Michael Siu, Victor Ryzhov
Two types of radical cations of tryptophan-the π-radical cation and the protonated tryptophan-N radical-have been studied in dipeptides AW and WA. The π-radical cation produced by removal of an electron during collision-induced dissociation of a ternary Cu(II) complex was only observed for the AW peptide. In the case of WA, only the ion corresponding to the loss of ammonia, [WA-NH3 ] •+ , was observed from the copper complex. Both protonated tryptophan-N radicals were produced by N-nitrosylation of the neutral peptides followed by transfer to the gas phase via electrospray ionization and subsequent collision-induced dissociation...
October 3, 2018: European Journal of Mass Spectrometry
Xiayan Zhang, Xu Xu, Xinmeng Chen, Lin Chen, Xiaoying Xu, Zhijun Wu, Dongmei Fang, Tian Cai
Sodium adducts of anti-2,3-dihydroxy-1-phenylpentane-1,4-dione compounds with different substituents were studied by collision-induced dissociation. McLafferty-type rearrangements preceding fragmentation were found as their main fragmentation pathway. Coordination of sodium cation to the oxygen functions may either lead to formation of a five-membered or a six-membered ring. Two McLafferty-type rearrangement product ions exhibiting a mass difference of 2 u indicated that two competitive McLafferty-type rearrangements through a six-membered ring coordination occurred...
September 25, 2018: European Journal of Mass Spectrometry
Shobha Devi, Yi-Cheng Lin, Yen-Peng Ho
A simple label-free method was developed for the quantification of the herbicide-resistant gene-related protein 5-enolpyruvylshikimate-3-phosphate synthase using multiple reaction monitoring liquid chromatography-mass spectrometry. Sample pretreatment procedures including ion exchange chromatography and CaCl2 precipitation were used to purify the 5-enolpyruvylshikimate-3-phosphate synthase protein. Quantification of various percentages of genetically modified soya (0.5-100%) was performed by selecting suitable endogenous soybean peptides as internal standards...
September 25, 2018: European Journal of Mass Spectrometry
Jos Oomens, Nicolas C Polfer, Giel Berden, John R Eyler
With the passing of Prof. Robert C. Dunbar on 31 October 2017, the field of ion chemistry lost one of its modern heroes. Throughout his career in mass spectrometry, two of his main research interests involved the interaction of trapped ions with electromagnetic radiation and the chelation motifs of metal ions with organic ligands. The focus of his early career was on the fundamental processes that take place in molecules upon ultraviolet and infrared excitation. From 2003 to 2017, his scientific interests shifted to more structural questions, notably to resolving the structures and binding motifs of metal ion chelation complexes by application of infrared photodissociation spectroscopy...
September 11, 2018: European Journal of Mass Spectrometry
Zachary J Devereaux, Y Zhu, M T Rodgers
The frequency and diversity of posttranscriptional modifications add an additional layer of chemical complexity beyond canonical nucleic acid sequence. Methylations are particularly frequently occurring and often highly conserved throughout the kingdoms of life. However, the intricate functions of these modified nucleic acid constituents are often not fully understood. Systematic foundational research that reduces systems to their minimum constituents may aid in unraveling the complexities of nucleic acid biochemistry...
September 6, 2018: European Journal of Mass Spectrometry
Zhe-Chen Wang, Ya-Ke Li, Sheng-Gui He, Veronica M Bierbaum
The strategy of synthesizing diazeniumdiolates (X-N(O)=NO- ) through the coexistence of nitric oxide and alkoxides (RO- ) was introduced by Wilhelm Traube 120 years ago. Today, despite the wide use of diazeniumdiolate derivatives to release nitric oxide in the treatment of cancer, the first step of the reaction mechanism for diazeniumdiolate synthesis remains a mystery and is thought to be complex. We have studied the gas-phase reactions of nitric oxide with alkoxides at room temperature. An electron-coupled hydrogen transfer is observed, and the radical anion HNO- is the only ionic product in these reactions...
September 6, 2018: European Journal of Mass Spectrometry
Xi Bai, Jumai Maitusong, Bakri Mahinur, Haji A Aisa, Maitinuer Maiwulanjiang
In this study, a method for the qualitative analysis of small molecular compounds in Schizonepeta annua (Pall.) Schischk essential oil was established based on gas chromatography-quadrupole time-of-flight mass spectrometry. In addition to an automated search of the NIST library, the identification of oxygenated monoterpenes, phenolic esters, and phenolic compounds was achieved by two additional strategies. One strategy involved comparing the relative errors of accurate masses measured for ions in the experimental spectra with those calculated for fragments identified from the NIST database of candidate matches...
August 2, 2018: European Journal of Mass Spectrometry
Gang Li, Detian Li, Yongjun Cheng, Wenjun Sun, Xiaoqiang Pei, Xiaodong Han, Huzhong Zhang, Yongjun Wang, Jian Sun, Meng Dong
A miniaturized linear ion trap mass spectrometer with continuous atmospheric pressure interface has been built in our lab. Significant extension in mass range and reduction in power consumption have been realized by the supplemental alternating current frequency scan mode. However, relatively poor sensitivity has been witnessed, which is directly dominated by the detection efficiency of the ion detector. Theoretical analysis has been implemented to find ways to improve the detection efficiency. The results show that enhanced sensitivity can be obtained by applying a direct current voltage on the pair of electrodes in eject direction...
August 2018: European Journal of Mass Spectrometry
Mohamed W Attwa, Adnan A Kadi, Hany W Darwish, Sawsan M Amer, Haitham Alrabiah
Foretinib (GSK1363089) is a multiple receptor tyrosine kinases inhibitor. In this study, a reliable, fast liquid chromatography-tandem mass spectrometric method was described for assaying foretinib in plasma, urine, and rat liver microsome samples. Simple extraction procedure by protein preciptation with acetonitrile was implemented for foretinib and brigatinib (internal standard) analysis. Chromatographic resolution of analytes was achieved on C18 column with the help of isocratic mobile phase. The binary mobile phase consisted of 60% ammonium formate (10 mM, pH 4...
August 2018: European Journal of Mass Spectrometry
Marvin Ihlenborg, Ann-Kathrin Schuster, Jürgen Grotemeyer, Frank Gunzer
Using lasers in ion mobility spectrometry offers a lot of advantages compared to standard ionization sources. Especially, the ion yield can be drastically increased. It can, however, reach levels where the Coulomb repulsion leads to unwanted side effects. Here, we investigate how the Coulomb repulsion can be detected apart from the typical signal broadening by measuring effects created already in the reaction region and comparing them with corresponding finite element method simulations.
August 2018: European Journal of Mass Spectrometry
Igors Susinskis, Peteris Mekss, Juris Hmelnickis
Unsymmetrical dimethyl hydrazine is highly toxic, carcinogenic compound, widely used for organic synthesis and drug development. Therefore, due to its high reactivity, direct analysis is problematic. Current study proposes to use derivatization reaction to increase selectivity and sensitivity of high-performance liquid chromatography-mass spectrometry method. Different derivatization agents were tested and optimal reaction media was found. Derivatization was performed by using small amounts of reagents to lower the cost of analysis...
August 2018: European Journal of Mass Spectrometry
N V Konenkov, M A Korzhavchikov, V A Stepanov, O E Trunina
Increase in quadrupole mass filter resolution at separation in narrow band stability island (X-band) formed by biharmonic resonance excitation of ion oscillation is discussed. X-band and the normal working quadrupole mass filter modes are compared at theoretical resolution of 10,000 and different separation times. Transmission curves, acceptance ellipses parameters, and acceptance characteristics are obtained by numerical simulation. Transmission coefficients are approximately the same in both modes. Dependence of acceptance ellipses parameters on ion inlet phases has a complicated oscillating form in the X-band mode...
August 2018: European Journal of Mass Spectrometry
Shanshan Wang, Yuanyuan Cheng, Mengmeng Chen, Kezhi Jiang
Differentiation of the isomeric haloanilines still remains a challenging and necessary analytic task due to their identical retention time in chromatography and similar mass spectra. In this work, p-tosylation of haloanilines by reaction of haloanilines with p-toluenesulfonyl chloride resulted in the corresponding N-tosyl haloanilines. Fragmentation of protonated N-tosyl haloanilines in electrospray ionization tandem mass spectrometry (ESI-MS/MS) mainly resulted in tosyl cation, haloaniline radical cation, and halohydroxyaniline radical cation...
August 2018: European Journal of Mass Spectrometry
Cheng Guo, Xuefeng Guo, Lei Zhao, Dandan Chen, Jin Wang, Jia Sun
Modified peptides fragmented by collision-induced dissociation can offer additional sequence information, which is beneficial for the de novo sequencing of peptides. Here, the model peptide VQGESNDLK was carbamylated. The optimal conditions were as follows: temperature of 90℃, pH of 7, and the time of 60 min. Then, we studied the b- and y-series ions of the native, carbamylated, and dual-modified peptides. The results were as follows. The short carbamylated peptides (≤10 amino acid residues) produced more b-series ions (including b1 ion)...
July 24, 2018: European Journal of Mass Spectrometry
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