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https://www.readbyqxmd.com/read/27914015/electron-transfer-dissociation-of-all-ions-at-all-times-ms-etd-in-a-quadrupole-time-of-flight-q-tof-mass-spectrometer
#1
Christian N Cramer, Jeffery M Brown, Nick Tomczyk, Peter Kresten Nielsen, Kim F Haselmann
Data-independent mass spectral acquisition is particularly powerful when combined with ultra-performance liquid chromatography (LC) that provides excellent separation of most components present in a given sample. Data-independent analysis (DIA) consists of alternating full MS scans and scans with fragmentation of all ions within a selected m/z range, providing precursor masses and structure information, respectively. Fragmentation spectra are acquired either by sequential isolation and fragmentation of sliding m/z ranges or fragmenting all ions entering the MS instrument with no ion isolation, termed broadband DIA...
December 2, 2016: Journal of the American Society for Mass Spectrometry
https://www.readbyqxmd.com/read/27913884/plasmid-pvax1-nh36-purification-by-membrane-and-bead-perfusion-chromatography
#2
Diana Ivonne Franco-Medrano, Patricia Guerrero-Germán, Rosa María Montesinos-Cisneros, Jaime Ortega-López, Armando Tejeda-Mansir
The demand for plasmid DNA (pDNA) has increased in response to the rapid advances in vaccines applications to prevent and treat infectious diseases caused by virus, bacteria or parasites, such as Leishmania species. The immunization protocols require large amounts of supercoiled plasmid DNA (sc-pDNA) challenging the development of efficient and profitable processes for capturing and purified pDNA molecules from large volumes of lysates. A typical bioprocess involves four steps: fermentation, primary recovery, intermediate recovery and final purification...
December 2, 2016: Bioprocess and Biosystems Engineering
https://www.readbyqxmd.com/read/27912967/qualitative-analysis-of-copaifera-oleoresin-using-comprehensive-two-dimensional-gas-chromatography-and-gas-chromatography-with-classical-and-cold-electron-ionisation-mass-spectrometry
#3
Yong Foo Wong, Thais M Uekane, Claudia M Rezende, Humberto R Bizzo, Philip J Marriott
Improved separation of both sesquiterpenes and diterpenic acids in Copaifera multijuga Hayne oleoresin, is demonstrated by using comprehensive two-dimensional gas chromatography (GC×GC) coupled to accurate mass time-of-flight mass spectrometry (accTOFMS). GC×GC separation employs polar phases (including ionic liquid phases) as the first dimension ((1)D) column, combined with a lower polarity (2)D phase. Elution temperatures (Te) of diterpenic acids (in methyl ester form, DAME) increased as the (1)D McReynolds' polarity value of the column phase decreased...
November 22, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27910788/metabolomic-investigation-of-rat-serum-following-oral-administration-of-the-willow-bracket-medicinal-mushroom-phellinus-igniarius-agaricomycetes-by-uplc-hdms
#4
Yu Dong, Ying He, Zhongming Yu, Yang Zhang, Nani Wang, Dan Shou, Changyu Li
The medicinal willow bracket mushroom, Phellinus igniarius, is a species that has been reported to possess antibacterial, antioxidative, antitumor, antidiabetic, and antihyperlipidemia activities. The aim of this study was to elucidate the changes in endogenous metabolites after oral administration of a decoction of Ph. Igniarius. Ultraperformance liquid chromatography (UPLC)/electrospray ionization synapt high-definition mass spectrometry (ESI-HDMS) combined with pattern recognition approaches, including principal component analysis and orthogonal partial least squares discriminant analysis, were integrated to discover differentiating metabolites...
2016: International Journal of Medicinal Mushrooms
https://www.readbyqxmd.com/read/27910729/identification-of-cytochrome-p450s-involved-in-the-metabolism-of-6-benzyl-1-benzyloxymethyl-5-iodouracil-w-1-using-human-recombinant-enzymes-and-rat-liver-microsomes-in-vitro
#5
Ying-Yuan Lu, Hai-Xu Cheng, Xin Wang, Xiao-Wei Wang, Jun-Yi Liu, Pu Li, Ya-Qing Lou, Jun Li, Chuang Lu, Guo-Liang Zhang
1. The aim of this study was to identify the hepatic metabolic enzymes, which involved in the biotransformation of 6-benzyl-1-benzyloxymethyl-5-iodouracil (W-1), a novel non-nucleoside reverse transcriptase inhibitor (NNRTIs) in rat and human in vitro. 2. The parent drug of W-1 was incubated with RLMs or recombinant CYPs (CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4 and CYP3A5, respectively) in the presence or absence of NADPH regenerating system. The metabolites of W-1 were analyzed with liquid chromatography-ion trap-time of flight-mass spectrometry (LC-IT-TOF-MS)...
December 2, 2016: Xenobiotica; the Fate of Foreign Compounds in Biological Systems
https://www.readbyqxmd.com/read/27908495/analysis-of-low-abundant-trehalose-6-phosphate-and-related-metabolites-in-medicago-truncatula-by-hydrophilic-interaction-liquid-chromatography-triple-quadrupole-mass-spectrometry
#6
Ana Teresa Mata, Tiago Filipe Jorge, João Ferreira, Maria do Rosário Bronze, Diana Branco, Pedro Fevereiro, Susana Araújo, Carla António
Trehalose-6-phosphate (T6P) is an important signaling metabolite involved in plant growth control that inhibits the sucrose nonfermenting-1-related protein kinase 1 (SnRK1), a key regulator of energy and carbon metabolism in plants. The quantification of T6P in plant tissues is fundamental to improve our understanding of sugar signaling and the links between plant growth and development in response to stress conditions. However, the almost undetectable levels of T6P together with the complex plant matrix and the presence of T6P isomers such as sucrose-6-phosphate (S6P), makes the detection of this metabolite challenging...
November 21, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27907868/purification-of-high-purity-glycyrrhizin-from-licorice-using-hydrophilic-interaction-solid-phase-extraction-coupled-with-preparative-reversed-phase-liquid-chromatography
#7
Wenyi Yu, Hongli Jin, Aijin Shen, Liang Deng, Jianlian Shi, Xingya Xue, Yadong Guo, Yanfang Liu, Xinmiao Liang
Glycyrrhizin (GA), a major bioactive compound in licorice, has been extensively used throughout the world as a medicine to treat chronic viral hepatitis and allergic dermatitis. In this study, a new method based on hydrophilic interaction solid phase extraction (HILIC-SPE) and preparative reversed-phase liquid chromatography (prep-RPLC) was developed to purify GA with high purity from the complex licorice extract. Via evaluation of retention behavior of GA and flavonoids in different commercially available columns, a hydrophilic column--Click XIon was finally chosen for the purification due to its excellent resolution toward GA and flavonoids under HILIC mode...
November 23, 2016: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/27904080/an-ic-ms-ms-method-for-the-determination-of-1-hydroxyethylidene-1-1-diphosphonic-acid-on-uncooked-foods-treated-with-peracetic-acid-based-sanitizers
#8
Ippei Suzuki, Hiroki Kubota, Takashi Ohtsuki, Chiye Tatebe, Atsuko Tada, Takeo Yano, Hiroshi Akiyama, Kyoko Sato
A rapid, sensitive, and specific analytical method for the determination of 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) on uncooked foods after treatment with a peracetic acid-based sanitizer (PAS) was developed. The method involves simple sample preparation steps and analysis using ion chromatography (IC) coupled with tandem mass spectrometry (MS/MS). The quantification limits of HEDP on uncooked foods are 0.007 mg/kg for vegetables and fruits and 0.2 mg/kg for meats. The recovery and relative standard deviation (RSD) of HEDP analyses of uncooked foods ranged from 73...
2016: Chemical & Pharmaceutical Bulletin
https://www.readbyqxmd.com/read/27904047/protective-effect-of-deer-bone-oil-on-cartilage-destruction-in-rats-with-monosodium-iodoacetate-mia-induced-osteoarthritis
#9
Hyeon-Son Choi, Suji Im, Je Won Park, Hyung Joo Suh
The anti-osteoarthritic activity of the methanol fraction of deer bone oil extract (DBO-M) was evaluated in interleukin (IL)-1β-inflamed primary rabbit chondrocytes and in rats with monosodium iodoacetate (MIA)-induced osteoarthritis. The active compound in DBO-M was analyzed using a direct infusion liquid chromatography quadrupole (LCQ) ion-trap electrospray ionization (ESI)-mass spectrometer (MS). DBO-M significantly suppressed the IL-1β-induced sulfated-glycosaminoglycan (s-GAG) release from chondrocyte, and lowered mRNA levels of the collagen-degrading enzymes matrix metalloproteinase (MMP)-1 and MMP-3 in a dose-dependent manner...
2016: Biological & Pharmaceutical Bulletin
https://www.readbyqxmd.com/read/27902942/a-simple-and-sensitive-liquid-chromatography-tandem-mass-spectrometry-method-for-trans-%C3%AE%C2%B5-viniferin-quantification-in-mouse-plasma-and-its-application-to-a-pharmacokinetic-study-in-mice
#10
Jiseon Kim, Jee Sun Min, Doyun Kim, Yu Fen Zheng, Karabasappa Mailar, Won Jun Choi, Choongho Lee, Soo Kyung Bae
In this study, a simple and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of trans-ε-viniferin in small volumes (10μl) of mouse plasma using chlorpropamide as an internal standard was developed and validated. Plasma samples were precipitated with acetonitrile and separated using an Eclipse Plus C18 column (100×4.6mm, 1.8-μm) with a mobile phase consisting of 0.1% formic acid in acetonitrile and 0.1% formic acid in water (60:40v/v) at a flow rate of 0.5ml/min...
November 24, 2016: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/27902449/is-n-n-dimethylglycine-n-oxide-a-choline-and-betaine-metabolite
#11
Michael Lever, Christopher J McEntyre, Peter M George, Stephen T Chambers
Choline metabolism is by oxidation to betaine, which is demethylated to N,N-dimethylglycine; dimethylglycine is oxidatively demethylated to sarcosine. This pathway is important for osmoregulation and as a source of methyl groups. We asked whether another metabolite was involved. We synthesized the N-oxide of dimethylglycine (DMGO) by oxidizing dimethylglycine with peracetic acid, and measured DMGO in human plasma and urine by HPLC-MS/MS with positive ion detection, using two chromatography procedures, based on ion exchange and HILIC separations...
November 30, 2016: Biological Chemistry
https://www.readbyqxmd.com/read/27900236/identification-of-two-sulfated-cholesterol-metabolites-found-in-the-urine-of-a-patient-with-niemann-pick-disease-type-c-as-novel-candidate-diagnostic-markers
#12
Masamitsu Maekawa, Kaoru Omura, Shoutaro Sekiguchi, Takashi Iida, Daisuke Saigusa, Hiroaki Yamaguchi, Nariyasu Mano
In the urine of a Niemann-Pick disease type C (NPC) patient, we have identified three characteristic intense peaks that have not been observed in the urine of a 3β-hydroxysteroid-Δ(5)-C27-steroid dehydrogenase deficiency patient or a healthy infant and adult. Based on accurate masses of the protonated molecules, we focused on two of them as candidate NPC diagnostic markers. Two synthesized authentic preparations agreed with the two compounds found in NPC patient urine in regard to both chromatographic behavior and accurate masses of the deprotonated molecules...
2016: Mass Spectrometry
https://www.readbyqxmd.com/read/27898784/effect-of-metal-ions-on-the-formation-of-trichloronitromethane-during-chlorination-of-catechol-and-nitrite
#13
Guojuan Gan, Rongwu Mei, Lin Qiu, Huachang Hong, Qingjun Wang, Asit Mazumder, Shikai Wu, Xiangliang Pan, Yan Liang
Catechol, nitrite, and dissolved metals are ubiquitous in source drinking water. Catechol and nitrite have been identified as precursors for halonitromethanes (HNMs), but the effect of metal ions on HNM formation during chlorination remains unclear. The main objective of this study was to investigate the effect of metal ions (Fe, Ti, Al) on the formation of trichloronitromethane (TCNM) (the most representative HNM species in disinfected water) on chlorinating catechol and nitrite. Trichloronitromethane was extracted by methyl tert-butyl ether and detected by gas chromatography...
November 2016: Journal of Environmental Quality
https://www.readbyqxmd.com/read/27896757/lc-ms-e-multiplex-ms-ms-ion-mobility-and-label-free-quantitation-in-clinical-proteomics
#14
Gustavo Henrique Martins Ferreira Souza, Paul C Guest, Daniel Martins-de-Souza
Proteomic tools can only be implemented in clinical settings if high-throughput, automated, sensitive, and accurate methods are developed. This has driven researchers to the edge of mass spectrometry (MS)-based proteomics capacity. Here we provide an overview of recent achievements in mass spectrometric technologies and instruments. This includes development of high and ultra definition-MS(E) (HDMS(E) and UDMS(E)) through implementation of ion mobility (IM) MS towards sensitive and accurate label-free proteomics using ultra performance liquid chromatography (UPLC)...
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/27894769/identification-of-molecular-species-of-monoalkyldiacylglycerol-from-the-squid-berryteuthis-magister-using-liquid-chromatography-apci-high-resolution-mass-spectrometry
#15
Viacheslav G Rybin, Andrey B Imbs, Darja A Demidkova, Ekaterina V Ermolenko
Monoalkyldiacylglycerol (MADAG) is an important lipid class in mollusks, corals, starfishes, and some species of zooplankton. Up to 80% of liver oils of squids and sharks are comprised of MADAG. Except for one fish species, there are no data on the composition of MADAG molecular species of marine organisms. The molecular species of MADAG obtained from digestive glands of the deep-sea squid Berryteuthis magister were identified. High-performance liquid chromatography (HPLC) and tandem high-resolution mass spectrometry (HRMS) with atmospheric pressure chemical ionization (APCI) were applied...
November 25, 2016: Chemistry and Physics of Lipids
https://www.readbyqxmd.com/read/27894695/the-performance-of-atmospheric-pressure-gas-chromatography-tandem-mass-spectrometry-compared-to-gas-chromatography-high-resolution-mass-spectrometry-for-the-analysis-of-polychlorinated-dioxins-and-pcbs-in-food-and-feed-samples
#16
Guillaume Ten Dam, Igor Cabreira Pussente, Georges Scholl, Gauthier Eppe, Alexander Schaechtele, Stefan van Leeuwen
Recently, gas chromatography tandem mass spectrometry (GC-MS/MS) has been added in European Union (EU) legislation as an alternative to magnetic sector high resolution mass spectrometry (HRMS) for the analysis of dioxins and dioxin like polychlorinated biphenyls (dl-PCB) in food and feed. In this study the performance of APGC-MS/MS compared to GC-HRMS is investigated and compared with EU legislation. The study includes the legislative parameters, relative intermediate precision standard deviation (SRw,rel), trueness, sensitivity, linear range and ion ratio tolerance...
November 22, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27891771/simultaneous-determination-of-trimethylamine-and-trimethylamine-n-oxide-in-mouse-plasma-samples-by-hydrophilic-interaction-liquid-chromatography-coupled-to-tandem-mass-spectrometry
#17
Si Mi, Yuan-Yuan Zhao, René L Jacobs, Jonathan M Curtis
A method was developed that applies hydrophilic interaction liquid chromatography with tandem mass spectrometry in the multiple-reaction monitoring mode to separate and accurately quantify trimethylamine and trimethylamine N-oxide in a single chromatographic run. This was achieved by converting trimethylamine to ethyl betaine, which is less volatile and hence results in greatly improved quantitation. Ethyl betaine also gives a similar response to trimethylamine N-oxide using positive ion electrospray ionization mass spectrometry...
November 28, 2016: Journal of Separation Science
https://www.readbyqxmd.com/read/27891187/mass-spectrometry-of-analytical-derivatives-2-ortho-and-para-effects-in-electron-ionization-mass-spectra-of-derivatives-of-hydroxy-mercapto-and-amino-benzoic-acids
#18
Nino G Todua, Anzor I Mikaia
Derivatives requiring either anhydrous or aqueous reaction conditions were prepared for robust and reliable gas chromatography/mass spectrometry (GC/MS) characterization of hydroxyl, mercapto, and amino benzoic acids Methylation and trialkylsilytation are employed for blocking the acidic function. Alkyl, trimethylsilyl, acetyl, perfluoroacyl and alkoxycarbonyl derivatization groups are introduced to hydroxyl, mercapto and amino functions. The electron ionization induced fragmentation characteristics of corresponding derivatives are explained by comparing the MS(1) spectra of unlabeled compounds to their (2)H and (13)C labeled analogs, and analysis of collision-induced dissociation data from MS(2) spectra...
2016: Mass Spektrom
https://www.readbyqxmd.com/read/27889756/liquid-chromatography-mass-spectrometry-reveals-the-effect-of-lactobacillus-treatment-on-the-faecal-metabolite-profile-of-rats-with-chronic-renal-failure
#19
Bin Wu, Hongli Jiang, Quan He, Meng Wang, Jinhong Xue, Hua Liu, Kehui Shi, Meng Wei, Shanshan Liang, Liwen Zhang
BACKGROUND/AIM: Chronic kidney disease is accompanied by changes in the gut microbiome and by an increase in the number of gut pathogenic bacteria. The aim of this study was to investigate the difference of the faecal metabolic profiles in rats with uremia, and to determine whether the altered metabolites in the rats with uremia can be restored by Lactobacillus. METHODS: Thirty rats were randomly divided into 3 groups: sham, uremia and uremia + probiotic (UP) groups...
November 26, 2016: Nephron
https://www.readbyqxmd.com/read/27889340/purification-and-characterization-of-an-antibacterial-and-anti-inflammatory-polypeptide-from-arca-subcrenata
#20
Yuyan Chen, Chunlei Li, Jianhua Zhu, Wangshi Xie, Xianjing Hu, Liyan Song, Jiachen Zi, Rongmin Yu
A polypeptide coded as PGC was isolated from Arca subcrenata muscle using ion exchange, Sephadex G-50 gel chromatography and RP-HPLC. PGC was identified to be a homogeneous compound by Native-PAGE and the purity was more than 98.9% measured by HPLC. The isoelectric point of PGC was determined to be 9.76 by IEF-PAGE. The molecular weight was determined to be 15973.0Da by ESI-MS/MS. The conformational structure of PGC was characterized by UV-vis, FT-IR and CD spectroscopy. N terminal amino acid sequence of PGC was shown as PSVYDAAAQLTADVKKDLRDSWKVIGGDKKGNGVA by Edman degradation...
November 23, 2016: International Journal of Biological Macromolecules
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