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Journal of Mass Spectrometry: JMS

François Fourel, Christophe Lécuyer, Magali Seris, Nigel Blamey, Uwe Brand, Philip Fralick, Filip Volders
We demonstrate an improved method based on Continuous Flow Elemental Analyser PYrolysis Isotopic Ratio Mass Spectrometry (CF-EA-PY-IRMS) to measure the 2 H/1 H ratios of water trapped in halite crystals. Two challenges to overcome are the low hydrogen concentration of samples (10 to 50 μmoles H2 .g-1 ) and the high chloride concentration released when reacting halite in an elemental analyser. We describe an optimization procedure for determining the 2 H/1 H ratio of this trapped water with an acceptable accuracy...
January 4, 2019: Journal of Mass Spectrometry: JMS
Kelly C O'Neill, Young-Jin Lee
Despite cyanoacrylate fuming being widely used in the forensic science field, its mechanism is not well understood. In this study, matrix assisted laser desorption/ionization (MALDI) mass spectrometry is used to study latent fingerprints that have been cyanoacrylate fumed in an attempt to gain insight into the fuming mechanism. In the negative mode mass spectrometry data, four compounds related to the polymerization of cyanoacrylate are identified and their structures are determined from accurate mass and MS/MS...
January 2, 2019: Journal of Mass Spectrometry: JMS
Annick Dion-Fortier, Alexia Gravel, Cassandra Guérette, Fanny Chevillot, Sonia Blais, Serge Auger, Pierre Picard, Pedro A Segura
Laser diode thermal desorption (LDTD) is an ionization source usually coupled to triple quadrupole mass spectrometry (QqQMS) and specifically designed for laboratories requiring high-throughput analysis. It has been observed that surface coatings on LDTD microwell plates can improve the sensitivity of the analysis of small polar molecules. The objective of the present study is to understand and quantify the effect of microwell surface coatings on signal intensity of small organic molecules of clinical, environmental and forensic interest...
January 2, 2019: Journal of Mass Spectrometry: JMS
Xiao Yang, Huang Huang, Qing Lu, Shao-Hong Chen, Feng Wang, Ou-Ping Huang, Bin Hu, Bi-Cheng Yang
Urinary biopterin (Bio) and neopterin (Neo) are important markers for clinical diagnosis of hyperphenylalaninemia. Herein, we developed a high-throughput analysis method based on electrospray ionization mass spectrometry (ESI-MS) with polymer tips for the rapid quantitative detection of Bio and Neo in clinical urine samples. Different polymer tips were investigated. It is found that the best detection sensitivity was achieved with hydrophobic polymer tip, i.e., polyethylene tips. The high-throughput polymer tip-ESI-MS method allowed a rapid analysis speed at ~ 40 sec per sample...
December 29, 2018: Journal of Mass Spectrometry: JMS
Tamar Shamai Yamin, Hagit Prihed, Avi Weissberg
A new analytical technique for the structural elucidation of four representative phenidate analogues possessing a secondary amine residue, which leads to a major/single amine-representative fragment/product ion at m/z 84 both in their GC-EI-MS and LC-ESI-MS/MS spectra, making their identification ambiguous, was developed. The method is based on "in vial" chemical derivatization with isobutyl chloroformate in both aqueous and organic solutions, followed by liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS/MS)...
December 29, 2018: Journal of Mass Spectrometry: JMS
T Fouquet, H Sato, Y Nakamichi, A Matsushika, H Inoue
A rapid analytical methodology is proposed to answer the two questions about the molecular and structural features of the acidic xylo-oligosaccharides (XOS) formed upon the enzymatic hydrolysis of 4-O-methylglucuronoxylan. The shortest acidic XOS carrying a methylglucuronic acid moiety and the possible distribution of larger products (molecular feature) are instantly found by ESI-MS in the negative ion mode which filters the unwanted neutral XOS. The acidic moiety is then unambiguously positioned along the xylose backbone (structural feature) by ESI-MSn in the negative ion mode via the selection /activation/dissociation of the product ions formed upon the one-way and stepwise glycosidic bond cleavage at the reducing end...
December 29, 2018: Journal of Mass Spectrometry: JMS
Asghar Amanpour, Hasim Kelebek, Serkan Selli
The current study was designed to find out how olive maturity indices (MI: 2.5, 3.5 and 4.5) affect the individual phenolic compounds and antioxidant potencies of olive oils produced from cv. Nizip Yaglik olives. Liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI-MS/MS) in multiple reaction monitoring (MRM) mode was utilized for the determination of phenolic composition qualitatively and quantitatively. Findings asserted a quite similar phenolic profile (14 phenols) depending on the various phenolic groups in all oils, while, the concentration of total and individual phenolic compounds revealed significant differences between the samples statistically (p<0...
December 28, 2018: Journal of Mass Spectrometry: JMS
Gabriela Petroselli, Tamara L Parapugna, M Gabriela Lagorio, Rosa Erra-Balsells
Yerba mate (YM) is massively produced and consumed as an infusion in South America and spreading all over the world. This product is obtained from dried leaves of Ilex paraguariensis Saint Hilaire, mixed with fragments of dried branches (sticks). For its commercialization YM must have a minimum percentage of leaves because its presence determines YMs quality and price. Till today a mechanical methodology to determine the relative amount of components (sticks, leaves, powder) is used. There is not any modern analytical method that provides information for quick characterization of the YM components...
December 26, 2018: Journal of Mass Spectrometry: JMS
Qingping Wang, Hanlan Liu, Marina Slavsky, Maria Fitzgerald, Chuang Lu, Thomas O'Shea
Reactive metabolites are thought to play a pivotal role in the pathogenesis of some drug induced liver injury (DILI) and idiosyncratic adverse drug reactions (IADRs), which is of concern to patient safety and has been a cause of drugs being withdrawn from the market place. To identify drugs with a lower propensity for causing DILI and /or IADRs, high-throughput assays to capture reactive metabolites are required in pharmaceutical industry for early drug discovery risk assessment. We describe the development of an assay to detect glutathione adducts with combined high sensitivity, enhanced specificity and rapid data analysis...
December 10, 2018: Journal of Mass Spectrometry: JMS
Anupam Giri, Marion Coutriade, Amandine Racaud, Pierre-Hugues Stefanuto, Koji Okuda, John Dane, Robert B Cody, Jean-François Focant
Comprehensive two-dimensional gas chromatography (GC×GC) coupled to time-of-flight mass spectrometry is a powerful separation tool for complex petroleum product analysis. However, the most commonly used electron ionization (EI) technique often makes the identification of the majority of hydrocarbons impossible due to the exhaustive fragmentation and lack of molecular ion preservation, prompting the need of soft-ionization energies. In this study, three different soft-ionization techniques including photo ionization (PI), chemical ionization (CI), and field ionization (FI) were compared against EI to elucidate their relative capabilities to reveal different base oil hydrocarbon classes...
December 7, 2018: Journal of Mass Spectrometry: JMS
Meihui Zhuang, Hongbao Li, Jun Jiang, Guangming Huang
Traditional degradation methods for N-nitrosamines are either confined with acid solution or required for additional chemical reagents to guarantee high reaction efficiency. Herein, we demonstrate a facile and effective way for reagent-free and pH-independent degradation of N-nitrosamines, which was induced by free electrons generated via corona discharge at ambient pressure. The highly reactive free electron is produced in situ and responsible for degradation of three N-nitrosamines, which was also theoretically confirmed...
December 7, 2018: Journal of Mass Spectrometry: JMS
C Lübbert, W Peukert
The presence of electrochemical reactions occurring in an electrospray processes at the point where the current enters the liquid is discussed since the early 1990&#x2019;s. This current transfer to the liquid requires in general oxidation or reduction of either electrolyte species in the liquid sprayed or of the electrode material in contact with the liquid. As a result new chemical species are generated. These products of the electrochemical reaction might be detected as altered species in mass spectra, they might be volatile and not recognized at all or accumulate on the electrode surface and cause cross contamination later on...
December 3, 2018: Journal of Mass Spectrometry: JMS
Zoé Deuscher, Isabelle Andriot, Etienne Sémon, Marie Repoux, Sébastien Preys, Jean-Michel Roger, Renaud Boulanger, Hélène Labouré, Jean-Luc Le Quéré
Direct-injection mass spectrometry (DIMS) techniques have evolved into powerful methods to analyse volatile organic compounds (VOCs) without the need of chromatographic separation. Combined to chemometrics, they have been used in many domains to solve samples categorization issues based on volatilome determination. In this paper, different DIMS methods that have largely outperformed conventional electronic noses (e-noses) in classification tasks are briefly reviewed, with an emphasis on food-related applications...
November 26, 2018: Journal of Mass Spectrometry: JMS
Takaya Murakami, Yoshiaki Iwamuro, Reiko Ishimaru, Satoshi Chinaka, Noriyuki Kato, Yuki Sakamoto, Natsuhiko Sugimura, Hiroshi Hasegawa
A reliable method for structural analysis is crucial for the forensic investigation of new psychoactive substances (NPSs). Towards this end, mass spectrometry is one of the most efficient and facile methods for the identification of NPSs. However, the differentiation among 2-, 3-, and 4-fluoromethcathinones (o-, m-, and p-FMCs), which are ring-fluorinated positional isomers part of the major class of NPSs referred to as synthetic cathinones, remains a challenge. This is mostly due to their similar retention properties and nearly identical full scan mass spectra, which hinder their identification...
November 24, 2018: Journal of Mass Spectrometry: JMS
Zhongping Huang, Yanshuxian Liu, Xiaoli Huang, Zhengzheng Hu, Huijun Liu, Lili Wang, Charles Liu, Yiping Ren
A novel method utilizing ambient thermal desorption ionization with a direct analysis in real-time source integrated with mass spectrometry (DART-MS) was established and applied to the rapid analysis of 3-hydroxy-3-methylglutaric (3-HMG) acid in the neonatal urine. Instrument parameter settings were optimized to obtain high sensitive and accurate determination of 3-HMG acid. The use of helium gas heated to temperature of 400 o C was observed to permit deprotonation, 3-HMG acid producing a abundant [M-H]- (m/z 161) in the negative ion mode...
November 23, 2018: Journal of Mass Spectrometry: JMS
Tobias Parchomyk, Konrad Koszinowski
Substitution reactions between gaseous ions and neutral substrate molecules are of ongoing high interest. To investigate these processes in a qualitative and quantitative manner, we have constructed a device, with which a defined amount of a volatile substrate can be mixed with a defined amount of helium gas and added into a three-dimensional quadrupole ion trap. From the known inner volume of the device, the known ratio nsubstrate :nHe of the mixture, and the determined absolute partial pressure of helium in the ion trap, we can derive the partial pressure of the substrate in the ion trap and, thus, convert the directly observable pseudo-first order rate constants of the substitution reactions into absolute bimolecular rate constants...
November 16, 2018: Journal of Mass Spectrometry: JMS
Syed Abdul Wadood, Guo Boli, Wei Yimin
The present study was aimed to investigate the variation of stable isotopic ratios of carbon, nitrogen, hydrogen, and oxygen in wheat kernel along with different processed fractions from three geographical origins across five years using isotope ratio mass spectrometry (IRMS). Multiway ANOVA revealed significant differences among region, harvest year, processing and their interactions for all isotopes. The region contributed the major variability in the δ13 C ‰, δ2 H ‰, δ15 N ‰, and δ18 O‰ values of wheat...
November 15, 2018: Journal of Mass Spectrometry: JMS
Dayujia Huo, Tai Qin, Lily Zu
Suppression of the selective cleavage at N-terminal of proline is observed in the peptide cleavage by proteolytic enzyme trypsin and in the fragment ion mass spectra of peptides containing Arg-Pro sequence. An insight into the fragmentation mechanism of the influence of arginine residue on the proline effect can help in prediction of mass spectra and in protein structure analysis. In this work, collision-induced dissociation spectra of singly and doubly charged peptide AARPAA were studied by ESI MS/MS and theoretical calculation methods...
November 13, 2018: Journal of Mass Spectrometry: JMS
Lei Li, Wen Li, Bin Hu
Rapid characterization of metabolites and risk compounds such as chemical residues and natural toxins in raw food materials such as vegetables, meats and edible living plants and animals plays an important part in ensuing food quality and safety. To rapidly characterize the analytes in raw food materials, it is essential to develop in situ method for directly analyzing raw food materials. In this work, raw food materials including biological tissues and living samples were placed between an electrode and mass spectrometric (MS) inlet under a strong electrostatic field, analytes were rapidly induced to generate electrospray ionization (ESI) from the sample tip by adding a drop of solvent onto the sample...
November 13, 2018: Journal of Mass Spectrometry: JMS
Rafał Frański
No abstract text is available yet for this article.
November 13, 2018: Journal of Mass Spectrometry: JMS
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