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Mass spectra

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
Minjie Zhao, Michel Mozeika Arau Jo, Stéphanie Dal, Séverine Sigrist, Martine Bergaentzlé, David Ramanitrahasimbola, Charles Andrianjara, Eric Marchioni
This study describes a selective and effective pressurized liquid extraction (PLE) coupled with HPLC-DAD-ESI/MS method for the identification and quantification of three fructosazine analogues (FZAs), fructosazine, 2,6- and 2,5-deoxyfructosazine in Madeglucyl(®) (MG) which is an ammonia treated extract of Eugenia jambolana Lamarck seeds, and is the world's first anti-diabetic phytodrug. FZAs were extracted from MG by PLE using methanol as extraction solvent. The PLE extract was then analyzed directly by HPLC-DAD-ESI/MS without cleanup step...
October 13, 2016: Journal of Chromatography. A
Yan Li, Mourad Harir, Marianna Lucio, Michael Gonsior, Boris P Koch, Philippe Schmitt-Kopplin, Norbert Hertkorn
Deciphering the molecular codes of dissolved organic matter (DOM) improves our understanding of its role in the global element cycles and its active involvement in ecosystem services. This study demonstrates comprehensive characterization of DOM by an initial polarity-based stepwise solid phase extraction (SPE) with single methanol elution of the cartridges, but separate collection of equal aliquots of eluate. The reduction of molecular complexity in the individual DOM fractions attenuates intermolecular interactions and substantially increases the disposable resolution of any structure selective characterization...
October 14, 2016: Water Research
Akiko Asada, Takahiro Doi, Takaomi Tagami, Akihiro Takeda, Yoshiyuki Sawabe
N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (APINACA) and N-(1-adamantyl)-1-pentyl-1H-indole-3-carboxamide (APICA) are carboxamide-type synthetic cannabinoids comprising indazole/indole-3-carboxylic acid and adamantan-1-amine moieties. However, in the case of compounds like APINACA or APICA, adamantyl positional isomers exist, wherein either adamantan-1-amine or adamantan-2-amine is present. These adamantyl positional isomers have not been reported in previous studies, and no analytical data are available yet...
October 21, 2016: Drug Testing and Analysis
Ariane Isis Barros, Diego Victor de Babos, Edilene Cristina Ferreira, José Anchieta Gomes Neto
Different precursors were evaluated for the generation of reference spectra and correction of the background caused by SiO molecules in the determination of Sb in facial cosmetics by high-resolution continuum source graphite furnace atomic absorption spectrometry employing direct solid sample analysis. Zeolite and mica were the most effective precursors for background correction during Sb determination using the 217.581nm and 231.147nm lines. Full 2(3) factorial design and central composite design were used to optimize the atomizer temperature program...
December 1, 2016: Talanta
A D Surowka, M Töpperwien, M Bernhardt, J D Nicolas, M Osterhoff, T Salditt, D Adamek, M Szczerbowska-Boruchowska
Human dopaminergic system in general, and substantia nigra (SN) neurons, in particular, are implicated in the pathologies underlying the human brain aging. The interplay between aberrations in the structural organization and elemental composition of SN neuron bodies has recently gained in importance as selected metals: Fe, Cu, Zn, Ca were found to trigger oxidative-stress-mediated aberration in their molecular assembly due to concomitant protein (alpha-synuclein, tau-protein) aggregation, gliosis and finally oxidative stress...
December 1, 2016: Talanta
Jiajia Li, Chunlai Ding, Zhengbiao Zhang, Xiangqiang Pan, Na Li, Jian Zhu, Xiulin Zhu
Butyl acrylate is polymerized in the living way under the irradiation of purple light-emitting diode (LED) or sunlight without photocatalyst at ambient temperature. 2-((Phenoxycarbonothioyl)thio) ethyl propanoate) is exclusively added and acted as an initiator and a chain transfer agent simultaneously in the current system. Poly(butyl acrylate) with well-regulated molecular weight and relatively narrow molecular weight distribution (Ð < 1.30) is synthesized. High conversion (>95%) can be achieved within several minutes...
October 21, 2016: Macromolecular Rapid Communications
Hong Zhang, Zheng Dan, Zhi-Jie Ding, Yuan-Zhi Lao, Hong-Sheng Tan, Hong-Xi Xu
A UPLC-PDA-QTOFMS-guided isolation strategy was employed to screen and track potentially new compounds from Garcinia oblongifolia. As a result, two new prenylated xanthones, oblongixanthones D and E (1-2), six new prenylated benzoylphloroglucinol derivatives, oblongifolins V-Z (3-7) and oblongifolin AA (8), as well as a known compound oblongifolin L (9), were isolated from the EtOAc-soluble fraction of an acetone extract of the leaves of Garcinia oblongifolia guided by UPLC-PDA-QTOFMS analysis. The structures of the new compounds were elucidated by 1D- and 2D-NMR spectroscopic analysis and mass spectrometry...
October 21, 2016: Scientific Reports
Katayoun Mahdavi Ara, Farhad Raofie
Essential oils and volatile components of pomegranate (Punica granatum L.) peel of the Malas variety from Meybod, Iran, were extracted using supercritical fluid extraction (SFE) and hydro-distillation methods. The experimental parameters of SFE that is pressure, temperature, extraction time, and modifier (methanol) volume were optimized using a central composite design after a (2(4-1)) fractional factorial design. Detailed chemical composition of the essential oils and volatile components obtained by hydro-distillation and optimum condition of the supercritical CO2 extraction were analyzed by GC-MS, and seventy-three and forty-six compounds were identified according to their retention indices and mass spectra, respectively...
July 2016: Journal of Food Science and Technology
Justin M Gorham, William A Osborn, Jeremiah W Woodcock, Keana C K Scott, John M Heddleston, Angela R Hight Walker, Jeffrey W Gilman
To better assess risks associated with nano-enabled products including multiwalled carbon nanotubes (MWCNT) within polymer matrices, it is important to understand how MWCNT are dispersed throughout the composite. The current study presents a method which employs imaging X-ray photoelectron spectroscopy (XPS) to chemically detect spatially segregated MWCNT rich regions at an epoxy composites surface by exploiting differential charging. MWCNT do not charge due to high conductivity and have previously been shown to energetically separate from their insulating surroundings when characterized by XPS...
January 2016: Carbon
Martin Wieczorek, Karl-Heinz Gührs, Thorsten Heinzel
Posttranslational acetylation of lysine residues has been discovered as multifaceted regulatory modification for various nuclear, cytoplasmic, and mitochondrial proteins. The implementation of high-resolution and high-throughput mass spectrometry (MS) approaches has led to the identification of a hitherto underappreciated, large number of acetylation sites for a broad spectrum of cellular proteins. In this chapter, we describe a comprehensive protocol for the purification of an in vivo-acetylated, ectopically expressed, FLAG-epitope tagged nonhistone protein through immunoprecipitation (IP)...
2017: Methods in Molecular Biology
Xin Ma, Jing Liu, Zhengxiang Zhang, Tao Bo, Yu Bai, Huwei Liu
RATIONALE: Quadrupole based tandem mass spectrometry (MS/MS) plays critical role in "omics" studies. However, when a particular m/z precursor is selected by the quadrupole, ions other than the precursor are not transmitted through, the sensitivity and dynamic range thus diminish. Therefore, separation techniques such as ion mobility (IM) is coupled with MS/MS to improve it. METHODS: In this workflow, every IM-mass spectrometry (MS) scan was followed by one high collision energy (CE) scan...
October 19, 2016: Rapid Communications in Mass Spectrometry: RCM
Jie Zhang, Jiao Peng, Xiaoyong Chen, Yajun Gong, Lesheng Wan, Fei Gao, Suran Gan, Feng Wei, Shuangcheng Ma, Jiachun Chen, Jing Nie
Snake bile, a precious traditional Chinese medicine (TCM), was used as the major ingredient of some Chinese patent drugs, such as Shedan Chuanbei powder and Shedan Chenpi powder for hundred years. However, there is still requirement for the comprehensive and definite composition of bile acids in snake bile. In order to rapidly identify the bile acids constituents in snake bile to avoid the adulteration, ultrahigh-performance liquid chromatography with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UPLC/ESI-QTOF-MS/MS) has been applied to conduct a qualitative analysis on snake bile acids...
October 11, 2016: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Monika Pietrowska, Hanna C Diehl, Grzegorz Mrukwa, Magdalena Kalinowska-Herok, Marta Gawin, Mykola Chekan, Julian Elm, Grzegorz Drazek, Anna Krawczyk, Dariusz Lange, Helmut E Meyer, Joanna Polanska, Corinna Henkel, Piotr Widlak
Determination of the specific type of thyroid cancer is crucial for the prognosis and selection of treatment of this malignancy. However, in some cases appropriate classification is not possible based on histopathological features only, and it might be supported by molecular biomarkers. Here we aimed to characterize molecular profiles of different thyroid malignancies using mass spectrometry imaging (MSI) which enables the direct annotation of molecular features with morphological pictures of an analyzed tissue...
October 17, 2016: Biochimica et Biophysica Acta
T Banach, M Bochniarz, P Łyp, Ł Adaszek, W Wawron, B Furmaga, M Skrzypczak, J Ziętek, S Winiarczyk
The aim of this study was to use matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) for the identification of coagulase-negative staphylococci (CNS) isolated from the milk of cows with subclinical mastitis. The study material consisted of 33 isolates of CNS, identified by the results of API Staph tests, obtained from the milk of cows with subclinical mastitis. Based on the spectra analyses, MALDI-TOF MS tests of 33 bacterial samples allowed identification of the microorganisms in 27 cases (81...
September 1, 2016: Polish Journal of Veterinary Sciences
Andrew P Storey, Offer M Zeiri, Steven J Ray, Gary M Hieftje
The flowing atmospheric-pressure afterglow (FAPA) source was used for the mass-spectrometric analysis of vapor samples introduced between the source and mass spectrometer inlet. Through interrupted operation of the plasma-supporting helium flow, helium consumption is greatly reduced and dynamic gas behavior occurs that was characterized by schlieren imaging. Moreover, mass spectra acquired immediately after the onset of helium flow exhibit a signal spike before declining and ultimately reaching a steady level...
October 18, 2016: Journal of the American Society for Mass Spectrometry
Catia Contado, Roberto Argazzi, Vincenzo Amendola
Many advanced industrial and biomedical applications that use silver nanoparticles (AgNPs), require that particles are not only nano-sized, but also well dispersed, not aggregated and not agglomerated. This study presents two methods able to give rapidly sizes of monodispersed AgNPs suspensions in the dimensional range of 20-100nm. The first method, based on the application of Mie's theory, determines the particle sizes from the values of the surface plasmon resonance wavelength (SPRMAX), read from the optical absorption spectra, recorded between 190nm and 800nm...
October 13, 2016: Journal of Chromatography. A
Matthias Holzlechner, Katharina Strasser, Elitsa Zareva, Luise Steinhaeuser, Hanna Birnleitner, Andrea Beer, Michael Bergmann, Rudolf Oehler, Martina Marchetti-Deschmann
Tissue-resident immune cells differ from the corresponding blood cells in many functional aspects. Although the proteome of blood immune cells is well investigated there are almost no data on tissue-resident immune cells. Here we explored the potential of MALDI-TOF-MS imaging (MSI) to investigate these cells in colon tissue, which exhibits a strong immune infiltration. MSI identified several proteinaceous markers that colocalized with specific structures of the colon such as mucosa or muscularis mucosae in six patients...
October 18, 2016: Journal of Proteome Research
Will Kew, Ian Goodall, David Clarke, Dušan Uhrín
Scotch Whisky is an important product, both culturally and economically. Chemically, Scotch Whisky is a complex mixture, which comprises thousands of compounds, the nature of which are largely unknown. Here, we present a thorough overview of the chemistry of Scotch Whisky as observed by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Eighty-five whiskies, representing the majority of Scotch Whisky produced and sold, were analyzed by untargeted high-resolution mass spectrometry. Thousands of chemical formulae were assigned for each sample based on parts-per-billion mass accuracy of FT-ICR MS spectra...
October 17, 2016: Journal of the American Society for Mass Spectrometry
Shaoyu Yang, Xueqin Chen, Yuelong Pan, Jiekai Yu, Xin Li, Shenglin Ma
The present study aimed to identify potential serum biomarkers for predicting the clinical outcomes of patients with advanced non-small cell lung cancer (NSCLC) treated with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR‑TKIs). A total of 61 samples were collected and analyzed using the integrated approach of magnetic bead‑based weak cation exchange chromatography and matrix‑assisted laser desorption/ionization‑time of flight‑mass spectrometry. The Zhejiang University Protein Chip Data Analysis system was used to identify the protein spectra of patients that are resistant and sensitive to EGFR‑TKIs...
October 11, 2016: Molecular Medicine Reports
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