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Rapid Communications in Mass Spectrometry: RCM

Mengmeng Chen, Guohua Zhu, Jiaxiang Xu, Huarong Zhang, Jinsong Liu, Kezhi Jiang
RATIONALE: Carcinogenic o-methylaniline is one of the banned aromatic amines in azo dyes, but it is very difficult to distinguish it from its noncarcinogenic isomers due to their identical retention time on chromatography and similar mass spectra. METHODS: Imidization of the isomeric methylanilines was carried out by treatment with benzaldehyde under mild conditions. The formed derivatives were analyzed by gas chromatography-mass spectrometry. Theoretical calculations were carried out on the Gaussian 03 program by using the density functional theory method at the B3LYP/6-311+G(d,p) level...
December 10, 2017: Rapid Communications in Mass Spectrometry: RCM
Daniel J Ryan, David Nei, Boone M Prentice, Kristie L Rose, Richard M Caprioli, Jeffrey M Spraggins
RATIONALE: Liquid extraction surface analysis (LESA) can be used to generate spatially-directed protein identifications in an imaging mass spectrometry (IMS) workflow. This approach involves the use of robotic micro-extractions coupled to online liquid chromatography (LC). We have characterized the extraction efficiency of this method as well as its ability to identify proteins from a matrix assisted laser/desorption ionization (MALDI) IMS experiment. METHODS: Proteins and peptides were extracted from transverse sections of a rat brain and sagittal sections of a mouse pup using liquid surface extractions...
December 10, 2017: Rapid Communications in Mass Spectrometry: RCM
Xiafen Xu, Xinhui Li, Xianrui Liang
RATIONALE: Metabolites of isoflavones raised great attention due to the potential bioactivities in recent years. However, the complex constituents of metabolic system and low level of metabolites made it difficult to analyze. Mass spectrometry (MS) method was applied in our metabolites identification and fragmentation pathways study due to the advantages of rapidity, sensitivity, and low level of sample consumption. METHODS: Three isoflavone glycosides and their metabolites were identified with using ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC/QTOF-MS)...
December 8, 2017: Rapid Communications in Mass Spectrometry: RCM
Malorie Mella, Brenda Schweitzer, Sabra Botch-Jones, Claude Mallet
RATIONALE: Analyzing tissue samples is routinely performed when liquid biological samples are not available for replicate analysis. Preparing complex matrices, such as tissue, for analysis can be time-consuming. Traditional sample preparation methods typically begin with homogenization followed by a sample clean up step such as liquid-liquid or solid phase extraction. Samples are typically eluted, evaporated and reconstituted prior to instrumental analysis. The aim of this project was to evaluate multi-dimensional chromatography's utility in reducing the amount of time from sample acquisition to analysis...
December 7, 2017: Rapid Communications in Mass Spectrometry: RCM
Yuyang He, Xiaobin Cao, Jianwei Wang, Huiming Bao
RATIONALE: Although being out of equilibrium, biomolecules in organisms have the potential to approach isotope equilibrium locally because enzymatic reactions are intrinsically reversible. A rigorous approach that can describe isotope distribution among biomolecules and their apparent deviation from equilibrium state is lacking, however. METHODS: Applying the concept of distance matrix in graph theory, we propose that apparent local isotope equilibrium among a subset of biomolecules can be assessed using an apparent fractionation difference (|Δα|) matrix, in which the differences between the observed isotope composition (δ') and the calculated equilibrium fractionation factor (1000lnβ) can be more rigorously evaluated than by using a previous approach for multiple biomolecules...
December 5, 2017: Rapid Communications in Mass Spectrometry: RCM
Byeong-Yeol Song, Seongshin Gwak, Minji Jung, Geummun Nam, Nam-Yee Kim
RATIONALE: Pesticide self-poisoning is a major suicide method in many agricultural communities worldwide. In addition, there are a number of known crime cases related to people being harmed by insecticides. Methomyl, a prohibited insecticide in the Republic of Korea, has high toxicity and is frequently used for self-poisoning. In this study, we investigated the source of origin of methamyl in a fatal poisoning case using stable isotope ratio analysis. METHODS: Two bottles of Soju from a crime scene were seized and nine different brands of methomyl products were collected from the neighborhood for analysis...
December 5, 2017: Rapid Communications in Mass Spectrometry: RCM
Sunil Kumar, Vikas Bajpai, Awantika Singh, Brijesh Kumar
RATIONALE: Catharanthus roseus is a well-known dicotyledonous medicinal plant containing diverse classes of bioactive terpene indole alkaloids (TIAs), in particular the anticancer agents, vinblastine and vincristine. In view of the commercial importance of these compounds there is an urgent need to develop an accurate and reliable method for the screening of TIAs from C. roseus. METHODS: A method for the separation and characterization of these compounds was developed using high performance liquid chromatography coupled with positive electrospray ionization quadrupole time of flight tandem mass spectrometry (HPLC/ESI-QTOF-MS/MS)...
November 26, 2017: Rapid Communications in Mass Spectrometry: RCM
Qiang Zhang, Yue Su, Xiaopan Liu, Yinlong Guo
RATIONALE: The direct detection of nonpolar and low-polarity solvent extracts of herbal medicine is difficulty by conventional electrospray ionization mass spectrometry (ESI-MS). This problem can be solved by solvent-assisted electrospray ionization mass spectrometry (SAESI-MS). With the help of assisted solvents (ESI-friendly solvents) at the tip of the spray needle, compounds (especially the low-polarity compounds) in nonpolar and low-polarity solvent extracts can be ionized directly...
November 25, 2017: Rapid Communications in Mass Spectrometry: RCM
Ifeoluwa Idowu, Olga Francisco, Philippe J Thomas, Wesley Johnson, Chris Marvin, Jörg Stetefeld, Gregg T Tomy
RATIONALE: There is a need for a validated method to improve detection limits and simultaneously quantify polycyclic aromatic compounds (PACs, both parent and alkylated homologues) in biota by gas chromatography-tandem mass spectrometry because of their environmental significance. The validation of the method was performed in accordance to the Eurachem Guide to Quality in Analytical Chemistry. METHODS: Gas chromatography coupled with a triple quadrupole mass spectrometer used in multiple reaction monitoring mode (MRM) was used for detection and quantification...
November 24, 2017: Rapid Communications in Mass Spectrometry: RCM
Ana C Zanatta, Angela Mari, Milena Masullo, Iracilda Zeppone Carlos, Wagner Vilegas, Sonia Piacente, Lourdes Campaner Dos Santos
RATIONALE: Actinocephalus divaricatus (Eriocaulaceae) is an important source of income for the rural communities as it is sold as an ornamental plant. To date, no investigation has been conducted concerning the chemical composition and biological studies of the aerial parts of A. divaricatus. METHODS: The methanolic extract of the aerial parts of this species was chemically characterized. We applied an analytical dereplication approach based on Liquid Chromatography coupled to High Resolution Orbitrap Mass Spectrometry in order to develop, identify and define rapidly the metabolite fingerprint of the aerial parts of A...
November 22, 2017: Rapid Communications in Mass Spectrometry: RCM
Yue Wu, Jin Chen, Zheyi Liu, Fangjun Wang
RATIONALE: Pyridoxal 5'-phosphate (PLP) cooperates with a variety of enzymes in all organisms for many important biological processes. The development of mass-spectrometry-based methodology for high throughput modification analyses could provide an alternative way for PLP identification. The present study aims to identify PLP modification. METHODS: More PLP site-determining information was obtained by introducing multistage activation (MSA) assisted collision induced dissociation (CID)...
November 22, 2017: Rapid Communications in Mass Spectrometry: RCM
Katryna A van Leeuwen, Paul D Prenzler, Danielle Ryan, Mauro Paolini, Federica Camin
RATIONALE: Typical storage in oak barrels release in distillates different degradation products such as vanillin, which play an important role in their flavour and aroma. The addition of vanillin, as well as other aroma compounds, of different origin is prohibited by European laws. As vanillin samples from different sources have different δ(13) C values, the δ(13) C value could be used to determine whether the vanillin is authentic (lignin-derived), or if it has been added from another source (e...
November 18, 2017: Rapid Communications in Mass Spectrometry: RCM
Shandilya Mahamuni Baira, Pradipbhai D Kalariya, Rakesh Nimbalkar, Prabha Garg, R Srinivas, M V N Kumar Talluri
RATIONALE: Forced degradation studies are useful for better understanding of the stability of active pharmaceutical ingredients and drugs and to generate information about drug degradation pathways and formation of degradation products (DPs). Identification of DPs plays a vital role in establishing the safety and therapeutic benefit of the drug. METHODS: Canagliflozin (CAN) was subjected to different stress conditions as per ICH guidelines (Q1A R2). All the DPs and the drug were well separated on Aquity CSH C18 (100 × 2...
November 14, 2017: Rapid Communications in Mass Spectrometry: RCM
O Brinkkemper, F Braadbaart, B van Os, A van Hoesel, A van Brussel, R Fernandes
RATIONALE: Isotopic analysis of archaeological charred plant remains offers useful archaeological information. However, adequate sample pre-treatment protocols may be necessary to provide a contamination-free isotopic signal while limiting sample loss and achieving a high throughput. Under these constraints research was undertaken to compare the performance of different pre-treatment protocols. METHODS: Charred archaeological plant material was selected for isotopic analysis (δ(13) C and δ(15) N values) by Isotope Ratio Mass Spectrometry (IRMS) from a variety of plant species, time periods, and soil conditions...
November 14, 2017: Rapid Communications in Mass Spectrometry: RCM
Leonard I Wassenaar, Cedric Douence, Mark Altabet, Pradeep Aggarwal
RATIONALE: The nitrogen and oxygen (δ(15) N, δ(18) O, δ(17) O) isotopic compositions of NO3(-) and NO2(-) are important tracers of nutrient dynamics in soil, rain, groundwater and the oceans. The Cd-azide method was used to convert NO3 or NO2 to N2 O for N and triple-O isotopic analyses by N2 O-laser spectrometry. A protocol for laser-based headspace isotope analyses was compared with isotope-ratio mass spectrometry. Lasers provide the ability to directly measure (17) O anomalies which can help discern atmospheric N sources...
November 13, 2017: Rapid Communications in Mass Spectrometry: RCM
Trevor K Decker, Yuan Tian, Joshua S McClellan, Linsey Bennett, Stephen A Lammert, Daniel E Austin, Aaron R Hawkins
RATIONALE: Ion trap mass spectrometers are beneficial due to their intrinsic sensitivity and specificity. Therefore, a portable version for in situ analysis of various compounds is very attractive. Miniaturization of ion traps is paramount to the portability of said mass spectrometers. METHODS: We developed an optimized design for a planar linear ion trap mass spectrometer, consisting of two trapping plates with photolithographically patterned electrodes. Each plate is constructed using a machined glass substrate and standard microfabrication procedures...
November 13, 2017: Rapid Communications in Mass Spectrometry: RCM
Jusuf M Khreis, Julia Reitshammer, Violaine Vizcaino, Kevin Klawitter, Linda Feketeová, Stephan Denifl
RATIONALE: Histidine (His) is an essential amino acid, whose side group consists of aromatic imidazole moiety that can bind a proton or metal cation and act as a donor in intermolecular interactions in many biological processes. While the dissociation of His monomer ions is well known, information on the kinetic energy released in the dissociation has been missing. METHODS: Using a new home built electrospray ionization (ESI) source adapted to a double focusing mass spectrometer of BxE geometry, we investigated the fragmentation reactions of protonated and deprotonated His, [His+H](+) and [His-H](-) , and the protonated His dimer [His2 +H](+) , accelerated to 6 keV in a high-energy collision with He gas...
November 6, 2017: Rapid Communications in Mass Spectrometry: RCM
Cian Monnin, Parsram Ramrup, Carolann Daigle-Young, Dajana Vuckovic
RATIONALE: Mobile phase additives in LC-MS are used to improve peak shape, analyte ionization efficiency and method coverage. Both basic and acidic mobile phases have been used successfully for negative ESI, but very few systematic investigations exist to date to justify the choice of mobile phase. Acetic acid was previously shown to improve ionization in untargeted metabolomics of urine, but has not been investigated in lipidomics. The goal of this study was to systematically compare the performance of acetic acid to other commonly employed additives in negative ESI-LC-MS lipidomics...
November 6, 2017: Rapid Communications in Mass Spectrometry: RCM
Wenying Wu, Yanjie Chu, Shixiao Wang, Xiaoyang Sun, Jingjing Zhang, Yannian Wang, Xiaohui Chen
RATIONALE: Pimavanserin, a selective serotonin 2A receptor inverse agonist, is a promising candidate for treating Parkinson's disease psychosis. Our previous study exhibited that there might be an existence of extensive metabolites of pimavanserin in rats. However, the metabolic fate of pimavanserin in vivo remains unknown. Thus, it is essential to develop an efficient method to investigate metabolic profile of pimavanserin in rats. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) to date has the highest mass measurement accuracy and resolution of any mass spectrometry platforms...
November 6, 2017: Rapid Communications in Mass Spectrometry: RCM
Kaijie Xiao, Yue Wang, Yun Shen, Yuyin Han, Zhixin Tian
RATIONALE: Most of the current popular tandem mass spectrometers have the capability of resolving the primary structures (monosaccharide composition, sequence, and linkage) of N-glycans; however, compositions or putative structures have mostly been reported so far. Identification and visualization tools of N-glycans are largely needed. METHODS: The isotopic mass-to-charge ratio and envelope fingerprinting algorithm, which has been successfully used for intact protein database search and identification, was adapted for N-glycan database search, and a stand-alone N-glycan database search engine GlySeeker for automated N-glycan identification and visualization was developed and successfully benchmarked...
November 3, 2017: Rapid Communications in Mass Spectrometry: RCM
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