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Journal of Mass Spectrometry: JMS

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https://www.readbyqxmd.com/read/28102926/sodiation-based-in-source-collision-for-profiling-of-pyranocoumarins-in-radix-peucedani-qianhu-utility-of-sodium-adducts-stability-with-in-source-collision
#1
Wei Yang, Yingfei Li, Chen Kang, Haiyu Zhao, Li Xiang, Chuan Li, Qiao Wang
Full scan mode of liquid chromatography-mass spectrometry equipped with an electrospray ionization source offers a chance on global detection of complicated components; however, the scan mode carries significant challenges in rapidly capturing information of analysts. Sodiation-based in-source collision was proposed here, as a technique for rapid detecting untargeted analytes in full scan analysis, which was based on the stability of sodium adducts and the nonselectivity of in-source collision. Then the technique was applied to profile of angular-type pyranocoumarins (APs) in Radix Peucedani, with full scan analysis performed at two specific in-source collision energy: a high energy 50 V that is tolerated by the sodium adducts of APs, and a low energy 10 V, at which abundant adducts were offered...
January 19, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28098959/influence-of-electronic-and-molecular-structure-on-the-fragmentation-dynamic-of-even-electron-carbocationic-triangulenes-and-helicenes-in-the-gas-phase
#2
Jakob Felix Hitzenberger, Agnes Uhl, Jürgen Schatz, Thomas Drewello
Stable, long-lived organic cations are directly transferred by electrospray ionization (ESI) from solution into the gas phase where their collision-induced dissociations (CID) are studied by tandem mass spectrometry. Three related types of triphenyl carbenium ions are investigated, in which the meta positions are either substituted by methoxy groups or tertiary nitrogen bridges, including Tetramethoxyphenylacridinium (TMPA(+) ), dimethoxyquinacridinium (DMQA(+) ) and triazatriangulenium (TATA(+) ) cations. These ions are triangular in shape with increasing degrees of planarity...
January 18, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28098404/esi-activity-of-br-bf4-clo4-and-bph4-anions-in-the-presence-of-li-and-nbu4-counter-ions
#3
Konrad Koszinowski, Friederike Lissy
To improve our understanding of the electrospray-ionization (ESI) process, we have subjected equimolar mixtures of salts A(+) X(-) (A(+)  = Li(+) , NBu4(+) ; X(-)  = Br(-) , ClO4(-) , BF4(-) , BPh4(-) ) in different solvents (CH3 CN, tetrahydrofuran, CH3 OH, H2 O) to negative-ion mode ESI and analyzed the relative ESI activity of the different anionic model analytes. The ESI activity of the large and hydrophobic BPh4(-) ion greatly exceeds that of the smaller and more hydrophilic anions Br(-) , ClO4(-) , and BF4(-) , which we ascribe to its higher surface activity...
January 18, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28098395/first-uhplc-ms-ms-method-coupled-with-automated-on-line-spe-for-quantification-both-of-tacrolimus-and-everolimus-in-peripheral-blood-mononuclear-cells-and-its-application-on-samples-from-co-treated-pediatric-patients
#4
Debora Pensi, Amedeo De Nicolò, Michele Pinon, Clarissa Pisciotta, Pier Luigi Calvo, Antonello Nonnato, Renato Romagnoli, Francesco Tandoi, Giovanni Di Perri, Antonio D'Avolio
Tacrolimus (TAC, FK-506) and everolimus (EVE, RAD001) are immunosuppressors used to treat pediatric patients undergoing liver transplantation. Their hematic TDM by liquid chromatography became standard practice. However, it does not always reflect concentrations at their active site. Our aim was to develop and validate a new method for the simultaneous TAC and EVE quantification into target cells: Peripheral-Blood-Mononuclear-Cells (PBMCs). PBMCs were collected using Cell-Preparation-Tubes; cells number and MCV were evaluated by an automatic cell counter...
January 18, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28087974/application-of-z-sinapinic-matrix-in-peptide-maldi-ms-analysis
#5
María L Salum, Silvana L Giudicessi, Tobías Schmidt De León, Silvia A Camperi, Rosa Erra-Balsells
Since introduction of sinapinic acid (SA) and α-cyano-4-hydroxycinnamic acid as matrices successful application of matrix assisted laser desorption/ionization mass spectrometry started for protein/polypeptides. Both show some limitations in short peptide analysis because matrix clusters are quite abundant. Cinnamics currently used are E-cinnamics. Here Z-SA as matrix for peptides is studied and compared with E-SA and CHCA. Minor number of clusters are always observed in the low m/z region allowing the detection of short peptides...
January 14, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28074623/characterization-and-application-of-a-self-aspirating-electrospray-source-with-pneumatic-assisted-ionization
#6
Quan Yu, Jianchao Zhang, Kai Ni, Xiang Qian, Xiaohao Wang
A single gas-assisted electrospray ion source developed for ambient mass spectrometry is introduced in this paper. Simultaneous self-aspiration and electrospray could be achieved by using a constant sheath gas flow supplied from a mini air pump. A gas dynamic study of the spray module is carried out for structural optimization. The entire device exhibits a simplified design and has been systematically characterized through both simulated and experimental investigations. According to the results, the ion source exhibited satisfactory stability and the ability for quantitative operation in routine electrospray ionization mass spectrometry...
January 11, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28074602/direct-maldi-ms-analysis-of-the-disulfide-bonds-in-peptide-using-thiosalicylic-acid-as-a-reactive-matrix
#7
Daiki Asakawa, Issey Osaka
The ability of a thiol-containing molecule, thiosalicylic acid (TSA), to function as a reactive matrix for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) analysis of peptides has been investigated. Although TSA has reducing characteristics, the use of TSA did not cause a reduction-induced MALDI in-source decay (MALDI-ISD), probably because of the weak interactions between the thiol group in TSA and the carboxyl oxygen in the peptide. In contrast, when peptides containing disulfide bonds were analyzed by MALDI with TSA as the matrix, the disulfide bond was partially cleaved owing to the reaction with TSA, producing TSA adducted peptides...
January 10, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28063268/evaluation-of-the-quality-of-herbal-teas-by-dart-tof-ms
#8
Jana Prchalová, František Kovařík, Aleš Rajchl
The paper focuses on the optimization, settings and validation of direct analysis in real time (DART) coupled with time of flight detector (TOF) when used for the evaluation of the quality of selected herbal teas (fennel, chamomile, nettle, linden, peppermint, thyme, lemon balm, marigold, sage, rose hip, St. John's Wort). The ionization mode, the optimal ionization temperature and the type of solvent for sample extraction were optimized. The characteristic compounds of the analysed herbal teas (glycosides, flavonoids, phenolic and terpenic substances, such as chamazulene, anethole, menthol, thymol, salviol, hypericin etc...
January 7, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28061011/simultaneous-enantiomeric-analysis-of-pharmacologically-active-compounds-in-environmental-samples-by-chiral-lc-ms-ms-with-a-macrocyclic-antibiotic-stationary-phase
#9
D Camacho-Muñoz, B Kasprzyk-Hordern
This paper presents a multi-residue method for direct enantioselective separation of chiral pharmacologically active compounds in environmental matrices. The method is based on chiral liquid chromatography and tandem mass spectrometry detection. Simultaneous chiral discrimination was achieved with a macrocyclic glycopeptide-based column with antibiotic teicoplanin as a chiral selector working under reverse phase mode. For the first time, enantioresolution was reported for metabolites of ibuprofen: carboxyibuprofen and 2-hydroxyibuprofen with this chiral stationary phase...
January 6, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/27966255/liquid-chromatography-quadrupole-time-of-flight-mass-spectrometry-identification-and-determination-of-tri-and-hexaaryl-chloro-imidazoles-in-sewage-sludge
#10
J Casado, G Castro, I Rodriguez, M Ramil, R Montes, R Cela
The identification and further quantification of 2-chloro-triarylimidazole (o-Cl-TAI) and its dimer (o-DCl-HABI) in sludge from a sewage treatment plant (STP) is reported for the first time. Liquid chromatography (LC) quadrupole time-of-flight (QTOF) mass spectrometry (MS) was used as analytical technique during screening and determination steps. Pollutants were identified following a post-run search strategy, applying the chlorine mass filter, and characterized by their accurate MS and product ion scan spectra...
December 14, 2016: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/27935159/de-novo-sequencing-of-highly-modified-therapeutic-oligonucleotides-by-hydrophobic-tag-sequencing-coupled-with-lc-ms
#11
Rieko Goto, Shin Miyakawa, Emire Inomata, Tomonori Takami, Junji Yamaura, Yoshikazu Nakamura
Correct sequences are prerequisite for quality control of therapeutic oligonucleotides. However, there is no definitive method available for determining sequences of highly modified therapeutic RNAs, and thereby most of the oligonucleotides have been used clinically without direct sequence determination. In this study, we developed a novel sequencing method called 'hydrophobic tag sequencing'. Highly modified oligonucleotides are sequenced by partially digesting oligonucleotides conjugated with a 5'-hydrophobic tag, followed by liquid chromatography-mass spectrometry analysis...
December 9, 2016: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/27884051/unexpected-interaction-between-deprotonated-biliverdin-and-alcohols-as-studied-by-esi-ms
#12
LETTER
Rafat Franski, Tomasz Kozik
No abstract text is available yet for this article.
November 24, 2016: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/27868274/apci-as-an-innovative-ionization-mode-compared-to-ei-and-ci-for-the-analysis-of-a-large-range-of-organophosphate-esters-using-gc-ms-ms
#13
Wafaa Halloum, Ronan Cariou, Gaud Dervilly-Pinel, Farouk Jaber, Bruno Le Bizec
Organophosphate esters (OPEs) are chemical compounds incorporated into materials as flame-proof and/or plasticizing agents. In this work, 13 non-halogenated and 5 halogenated OPEs were studied. Their mass spectra were interpreted and compared in terms of fragmentation patterns and dominant ions via various ionization techniques (electron ionization (EI) and chemical ionization (CI) under vacuum and corona discharge atmospheric pressure chemical ionization (APCI)) on gas chromatography coupled to mass spectrometry (GC-MS)...
November 21, 2016: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/27859931/a-study-of-enhanced-ion-formation-from-metal-semiconductor-complexes-in-atmospheric-pressure-laser-desorption-ionization-mass-spectrometry
#14
Yuliya E Silina, Petra Herbeck-Engel, Marcus Koch
The study of the key parameters impacted surface-assisted laser desorption/ionization-mass spectrometry (SALDI-MS) is of broad interest. In previous studies, it has been shown that SALDI-MS is a complex process depending on multiple factors. In the presented study, we showed that neither porosity, light absorbance nor surface hydrophobicity alone influence the enhancement phenomena observed from the hybrid metal-semiconductor complexes versus individual targets, but small changes in the analyte attaching to the target significantly affect laser desorption ionization (LDI)-efficiency...
November 18, 2016: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/27790795/development-and-application-of-an-uhplc-ms-ms-method-for-the-simultaneous-determination-of-17-steroidal-hormones-in-equine-serum
#15
Michele Genangeli, Giovanni Caprioli, Manuela Cortese, Fulvio Laus, Mara Matteucci, Riccardo Petrelli, Massimo Ricciutelli, Gianni Sagratini, Stefano Sartori, Sauro Vittori
A new, fast and simple analytical method that is able to identify and quantify simultaneously 17 steroid hormones and metabolites (Pregnenolone, 17-OH-Pregnenolone, Progesterone, 17-OH Progesterone, Androsterone, Androstenedione, DHEA, DHEAS, Testosterone, Cortisol, Corticosterone, Aldosterone, 11-Deoxycortisol, 11-Deoxycorticosterone, Dihydrotestosterone, Estrone, Estradiol) has been developed in equine serum using the UHPLC-MS/MS technique. 400 μL of sample were deproteinized with 1000 µl of acetonitrile, evaporated, restored with 50 µl of a solution of 25% methanol and injected in UHPLC-MS/MS triple quadrupole...
October 27, 2016: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/27776380/sanist-optimization-of-a-technology-for-compound-identification-based-on-the-european-union-directive-with-applications-in-forensic-pharmaceutical-and-food-analyses
#16
Simone Cristoni, Guglielmo Dusi, Paolo Brambilla, Adriana Albini, Matteo Conti, Maura Brambilla, Antonino Bruno, Francesca Digaudio, Luca Ferlin, Valeria Tazzari, Silvia Mengozzi, Simone Barera, Carlos Salier, Tommaso Trenti, Marco Cantu, Luigi Rossi Bernardi, Douglas M Noonan
Electrospray Ionization (EI) and Collision Induced Dissociation tandem mass spectrometry (CID-MS/MS) are usually employed to obtain compound identification through a mass spectra match. Different algorithms have been developed for this purpose (for example the NIST match algorithm). These approaches compare the tandem mass spectra (MS/MS) of the unknown analyte with the MS/MS spectra of known compounds inserted in a database. The compounds are usually identified on the basis of spectral match value associated with a probability of recognition...
October 24, 2016: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/27862610/effects-of-covalent-modification-by-4-hydroxy-2-nonenal-on-the-noncovalent-oligomerization-of-ubiquitin
#17
Giuseppe Grasso, Paul H Axelsen
When lipid membranes containing ω-6 polyunsaturated fatty acyl chains are subjected to oxidative stress, one of the reaction products is 4-hydroxy-2-nonenal (HNE)-a chemically reactive short chain alkenal that can covalently modify proteins. The ubiquitin proteasome system is involved in the clearing of proteins modified by oxidation products such as HNE, but the chemical structure, stability and function of ubiquitin may be impaired by HNE modification. To evaluate this possibility, the susceptibility of ubiquitin to modification by HNE has been characterized over a range of concentrations where ubiquitin forms non-covalent oligomers...
January 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/27917611/high-mass-and-spatial-resolution-mass-spectrometry-imaging-of-nicolas-poussin-painting-cross-section-by-cluster-tof-sims
#18
M Noun, E Van Elslande, D Touboul, H Glanville, S Bucklow, P Walter, A Brunelle
The painting Rebecca and Eliezer at the Well, which hangs in the Fitzwilliam Museum, Cambridge, UK, is possibly one of the last figure painting executed by Nicolas Poussin at the very end of his life and is usually dated to the early 1660s. In this perspective special feature, Philippe Walter, Alain Brunelle and colleagues give new insights on the artist's working methods by a careful stateof-the-art imaging ToF-SIMS study of one sample taken on the edge of the painting. This approach allowed for the identification of the pigments used in the painting, their nature and components and those of the ground and preparatory layers, with the identification of the binder(s) and possible other additions of organic materials such as glue...
December 2016: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/27723220/medical-swab-touch-spray-mass-spectrometry-for-newborn-screening-of-nicotine-and-cotinine-in-meconium
#19
Bi-Cheng Yang, Feng Wang, Xiao Yang, Wei Zou, Jia-Chun Wang, Yang Zou, Fa-Ying Liu, Huai Liu, Ou-Ping Huang
Newborn screening is one of public health concerns designed to screen infants shortly after birth. Prenatal exposure to tobacco smoke such as nicotine has been reported to affect babies. Levels of nicotine and cotinine in meconium were widely used to evaluate the tobacco exposure of foetuses during pregnancy in a polluted environment. In this study, medical swabs were applied by using touch spray-mass spectrometry (TS-MS) to collect meconium from newborn infants for detection of nicotine and cotinine. Parameters such as choice of spray solvents, solvent volume and collision energy for screening of nicotine and cotinine were optimized...
December 2016: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/27706870/mass-spectrometric-monitoring-of-oxidation-of-aliphatic-c6-c8-hydrocarbons-and-ethanol-in-low-pressure-oxygen-and-air-plasmas
#20
Dilshadbek T Usmanov, Lee Chuin Chen, Kenzo Hiraoka, Hiroshi Wada, Hiroshi Nonami, Shinichi Yamabe
Experimental and theoretical studies on the oxidation of saturated hydrocarbons (n-hexane, cyclohexane, n-heptane, n-octane and isooctane) and ethanol in 28 Torr O2 or air plasma generated by a hollow cathode discharge ion source were made. Ions corresponding to [M + 15](+) and [M + 13](+) in addition to [M - H](+) and [M - 3H](+) were detected as major ions where M is the sample molecule. The ions [M + 15](+) and [M + 13](+) were assigned as oxidation products, [M - H + O](+) and [M - 3H + O](+) , respectively...
December 2016: Journal of Mass Spectrometry: JMS
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