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Ion mobility spectrometry

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https://www.readbyqxmd.com/read/28531844/development-of-an-uplc-ms-ms-method-for-simultaneous-quantitation-of-11-d-amino-acids-in-different-regions-of-rat-brain-application-to-a-study-on-the-associations-of-d-amino-acid-concentration-changes-and-alzheimer-s-disease
#1
Zhe Li, Yuping Xing, Xingjie Guo, Yan Cui
There are significant differences in d-amino acid concentrations between healthy people and Alzheimer's disease patients. In order to investigate the potential correlation between d-amino acids and Alzheimer's disease, a simple and sensitive ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method has been developed. The method was applied to simultaneous determination of 11 d-amino acids in different regions of rat brain. Rat brain homogenates were firstly pretreated with protein precipitation procedure and then derivatized with (S)-N-(4-nitrophenoxycarbonyl) phenylalanine methoxyethyl ester [(S)-NIFE]...
May 11, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28530810/seleniranium-ions-undergo-%C3%AF-ligand-exchange-via-an-associative-mechanism-in-the-gas-phase
#2
Shea Fern Lim, Benjamin Leigh Harris, George N Khairallah, Evan John Bieske, Philippe Maître, Gabriel da Silva, Brian D Adamson, Michael S Scholz, Neville J A Coughlan, Richard A J O'Hair, Michael Rathjen, Daniel Stares, Jonathan M White
Collision-induced dissociation mass spectrometry of the ammonium ions 4a and 4b results in the formation of the seleniranium ion 5, the structure and purity of which was verified using gas phase infra-red spectroscopy coupled to mass spectrometry, and gas phase ion-mobility measurements. Ion-molecule reactions between the ion 5 (m/z = 261) and cyclopentene, cyclohexene, cycloheptene and cyclooctene, resulted in the formation of the seleniranium ions 7 (m/z = 225), 6 (m/z = 239), 8 (m/z = 253), and 9 (m/z = 267) respectively...
May 22, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28528542/performance-of-a-high-pressure-liquid-chromatography-ion-mobility-mass-spectrometry-system-for-metabolic-profiling
#3
Xing Zhang, Kimberly Kew, Richard Reisdorph, Mark Sartain, Roger Powell, Michael L Armstrong, Kevin Quinn, Charmion Cruickshank-Quinn, Scott Walmsley, Samantha S Bokatzian, Ed Darland, Matthew Rain, Kenneth Imatani, Nichole Reisdorph
A commercial liquid chromatography/drift tube ion mobility-mass spectrometer (LC/IM-MS) was evaluated for its utility in global metabolomics analysis. Performance was assessed using twelve targeted metabolite standards where the limit of detection (LOD), linear dynamic range, resolving power, and collision cross section (Ω), is reported for each standard. Data was collected in three different instrument operation modes: flow injection analysis with IM-MS (FIA/IM-MS), LC/MS and LC/IM-MS. Metabolomics analyses of human plasma and HaCaT cells were used to compare the above three operation modes...
May 22, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28521538/correction-to-raninen-lappi-kolehmainen-kolehmainen-mykk%C3%A3-nen-poutanen-and-raatikainen-diet-derived-changes-by-sourdough-fermented-rye-bread-in-exhaled-breath-aspiration-ion-mobility-spectrometry-profiles-in-individuals-with-mild-gastrointestinal-symptoms
#4
https://www.readbyqxmd.com/read/28521276/an-atmospheric-pressure-ionization-source-using-a-high-voltage-target-compared-to-electrospray-ionization-for-the-lc-ms-analysis-of-pharmaceutical-compounds
#5
Arnaud Lubin, Ronald De Vries, Deirdre Cabooter, Patrick Augustijns, Filip Cuyckens
The type and design of an ionization source can have a significant influence on the performances of a bioanalytical method. It is, therefore, of high interest to evaluate the performances of newly introduced sources to highlight their benefits and limitations in comparison to other well established sources. In this paper, liquid chromatography - mass spectrometry (LC/MS) performances of a new atmospheric pressure ionization (API) source, commercialized as UniSpray, is evaluated. The dynamic range of 24 pharmaceutical and biological compounds is compared between the new API source and electrospray ionization (ESI) for 3 different mobile phase conditions...
May 4, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28513924/glycan-fingerprinting-using-cold-ion-infrared-spectroscopy
#6
Eike Mucha, Ana Isabel González Flórez, Mateusz Marianski, Daniel A Thomas, Waldemar Hoffmann, Weston B Struwe, Heung S Hahm, Sandy Gewinner, Wieland Schöllkopf, Peter H Seeberger, Gert von Helden, Kevin Pagel
The diversity of stereochemical isomers present in glycans and glycoconjugates poses a formidable challenge for comprehensive structural analysis. Typically, sophisticated mass spectrometry (MS)-based techniques are used in combination with chromatography or ion mobility separation. However, coexisting structurally similar isomers often render an unambiguous identification impossible. Other powerful techniques such as gas-phase infrared (IR) spectroscopy have been limited to smaller glycans, as conformational flexibility and thermal activation during the measurement result in poor spectral resolution...
May 17, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28511118/simultaneous-determination-of-selective-serotonin-reuptake-inhibitors-and-their-main-metabolites-in-human-breast-milk-by-liquid-chromatography-electrospray-mass-spectrometry
#7
Etienne Weisskopf, Alice Panchaud, Kim An Nguyen, Delphine Grosjean, Jean-Michel Hascoët, Chantal Csajka, Chin B Eap, Nicolas Ansermot
A bioanalytical method by high performance liquid chromatography coupled to electrospray mass spectrometry (HPLC-ESI-MS), adapted from a previously published method in plasma, was validated in breast milk for the simultaneous quantification of all antidepressants belonging to the class of selective serotonin reuptake inhibitors (citalopram, fluoxetine, fluvoxamine, paroxetine and sertraline) and their major metabolites (desmethylcitalopram and norfluoxetine). Milk samples (250μl) first underwent protein precipitation followed by solid-phase extraction on a reversed phase/cation exchange sorbent...
July 1, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28505408/ion-mobility-hydrogen-deuterium-exchange-and-isotope-scrambling-tools-to-aid-compound-identification-in-omics-mixtures
#8
Hossein Maleki, Megan M Maurer, Nima Ronaghi, Stephen J Valentine
Liquid chromatography tandem mass spectrometry (LC-MS/MS), a widely used method for comparative 'omics analysis, experiences challenges with compound identification due to matrix effects, difficulty in separating isomer and isobaric ions, and long analysis times. Ion mobility spectrometry (IMS) has proven to be useful in separating isomer and isobar ions, however IMS-MS suffers from decreased peak capacity duet to the correlation in ion size and mass. In proof-of-principle experiments, the use of gas-phase hydrogen/deuterium exchange (HDX) combined with IMS-MS/MS techniques is demonstrated to offer advantages for compound identification...
May 15, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28505286/pixie-an-algorithm-for-automated-ion-mobility-arrival-time-extraction-and-collision-cross-section-calculation-using-global-data-association
#9
Jian Ma, Cameron P Casey, Xueyun Zheng, Yehia M Ibrahim, Christopher S Wilkins, Ryan S Renslow, Dennis G Thomas, Samuel H Payne, Matthew E Monroe, Richard D Smith, Justin G Teeguarden, Erin S Baker, Thomas O Metz
Motivation: Drift tube ion mobility spectrometry coupled with mass spectrometry (DTIMS-MS) is increasingly implemented in high throughput omics workflows, and new informatics approaches are necessary for processing the associated data. To automatically extract arrival times for molecules measured by DTIMS at multiple electric fields and compute their associated collisional cross sections (CCS), we created the PNNL Ion Mobility Cross Section Extractor (PIXiE). The primary application presented for this algorithm is the extraction of data that can then be used to create a reference library of experimental CCS values for use in high throughput omics analyses...
May 15, 2017: Bioinformatics
https://www.readbyqxmd.com/read/28502166/grouping-of-petroleum-substances-as-example-uvcbs-by-ion-mobility-mass-spectrometry-to-enable-chemical-composition-based-read-across
#10
Fabian Alexander Grimm, William K Russell, Yu-Syuan Luo, Yasuhiro Iwata, Weihsueh A Chiu, Tim Roy, Peter J Boogaard, Hans B Ketelslegers, Ivan Rusyn
Substances of Unknown or Variable composition, Complex reaction products, and Biological materials (UVCBs), including many refined petroleum products, present a major challenge in regulatory submissions under the EU Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) and US High Production Volume regulatory regimes. The inherent complexity of these substances, as well as variability in composition obfuscates detailed chemical characterization of each individual substance and their grouping for human and environmental health evaluation through read-across...
May 14, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28500372/ion-mobility-mass-spectrometry-as-a-tool-to-investigate-protein-ligand-interactions
#11
REVIEW
Melanie Göth, Kevin Pagel
Ion mobility-mass spectrometry (IM-MS) is a powerful tool for the simultaneous analysis of mass, charge, size, and shape of ionic species. It allows the characterization of even low-abundant species in complex samples and is therefore particularly suitable for the analysis of proteins and their assemblies. In the last few years even complex and intractable species have been investigated successfully with IM-MS and the number of publications in this field is steadily growing. This trend article highlights recent advances in which IM-MS was used to study protein-ligand complexes and in particular focuses on the catch and release (CaR) strategy and collision-induced unfolding (CIU)...
May 13, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28495090/separation-of-ten-phosphorylated-mono-and-disaccharides-using-hilic-and-ion-pairing-interactions
#12
Caroline Mathon, Gregory A Barding, Cynthia K Larive
Phosphorylated carbohydrates are indispensable cogs in several key metabolic wheels for all forms of life. Here, a straightforward liquid chromatography method coupled to mass spectrometry detection was developed for phosphorylated sugars. For separation of the targeted compounds, hydrophilic interaction chromatography (HILIC) was used with a bridged-ethylene hybrid amide column under alkaline conditions using triethylamine as a mobile phase modifier. Methylphosphonic acid was added to the aqueous mobile phase to reduce the tailing of compounds containing phosphate groups, which are known to interact with stainless steel components of the separation system...
June 15, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28495020/uplc-ms-ms-method-for-determination-of-sofosbuvir-in-human-plasma
#13
B M Gandhi, A L Rao, J V Rao
INTRODUCTION: A sensitive and rapid method for quantitation of Sofosbuvir in human plasma has been established using ultra performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS). MATERIALS AND METHODS: Sofosbuvir d3 was used as an internal standard. Sofosbuvir and internal standard in plasma sample were extracted using ethyl acetate (liquid liquid extraction). A centrifuged upper layer was then evaporated and reconstituted with the mobile phase of 0...
May 8, 2017: Annales Pharmaceutiques Françaises
https://www.readbyqxmd.com/read/28493423/development-and-validation-of-a-sensitive-uhplc-ms-ms-method-for-quantitative-analysis-of-farrerol-in-rat-plasma-application-to-pharmacokinetic-and-bioavailability-studies
#14
Li Piao, Mingcui Zang, Yue Gu, Baohua Liu
Farrerol is a 2,3-dihydro-flavonoid isolated from rhododendron. In this study, a sensitive and selective ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for the determination of farrerol in rat plasma. Liquid-liquid extraction by ethyl ether was used for sample preparation. Chromatographic separation was achieved on an Agilent UHPLC XDB-C18 column (2.1 mm × 100 mm, 1.8 µm) with water and methanol (30:70, v/v) as the mobile phase. An electrospray source was applied and operated in negative ion mode; selection reaction monitoring was used for quantification using target fragment ions m/z 299 → 179 for farrerol and m/z 267 → 252 for internal standard...
May 10, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/28487120/surface-anchored-counterions-on-weak-chiral-anion-exchangers-accelerate-separations-and-improve-their-compatibility-for-mass-spectrometry-hyphenation
#15
Ulrich Woiwode, Adrian Sievers-Engler, Aleksandra Zimmermann, Wolfgang Lindner, Orlando L Sánchez-Muñoz, Michael Lämmerhofer
In the present work we propose new variants of chiral stationary phases (CSP) with tert-butylcarbamoylquinine (tBuCQN) as chiral selector molecule. Four tBuCQN-CSPs with distinct bonding chemistries are compared in terms of their pH-dependent surface charge by ζ-potential determinations, by achiral and chiral liquid chromatographic tests and LC-ESI-MS hyphenation. In one embodiment tBuCQN was immobilized on 3-mercaptopropylmethylsilyl-modified silica by thiol-ene click reaction (brush type CSP with selector coverage of 0...
April 28, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28485775/determination-of-phloroglucinol-by-hplc-ms-ms-and-its-application-to-a-bioequivalence-study-in-healthy-volunteers
#16
X-Q Li, R-T Wang, Q-H Wang, X-L Tang, C-T Lu, H-G Gong, A-D Wen
OBJECTIVE: The aim of this study was to compare the pharmacokinetic characteristics of phloroglucinol between an orally disintegrating tablet and an orally lyophilized tablet of phloroglucinol in healthy volunteers under fasting condition. PATIENTS AND METHODS: A rapid and simple method based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method has been developed and validated for the determination of phloroglucinol in human plasma...
April 2017: European Review for Medical and Pharmacological Sciences
https://www.readbyqxmd.com/read/28484973/investigating-the-structural-compaction-of-biomolecules-upon-transition-to-the-gas-phase-using-esi-twims-ms
#17
Paul W A Devine, Henry C Fisher, Antonio N Calabrese, Fiona Whelan, Daniel R Higazi, Jennifer R Potts, David C Lowe, Sheena E Radford, Alison E Ashcroft
Collision cross-section (CCS) measurements obtained from ion mobility spectrometry-mass spectrometry (IMS-MS) analyses often provide useful information concerning a protein's size and shape and can be complemented by modeling procedures. However, there have been some concerns about the extent to which certain proteins maintain a native-like conformation during the gas-phase analysis, especially proteins with dynamic or extended regions. Here we have measured the CCSs of a range of biomolecules including non-globular proteins and RNAs of different sequence, size, and stability...
May 8, 2017: Journal of the American Society for Mass Spectrometry
https://www.readbyqxmd.com/read/28484808/analysis-of-listeria-using-exogenous-volatile-organic-compound-metabolites-and-their-detection-by-static-headspace-multi-capillary-column-gas-chromatography-ion-mobility-spectrometry-shs-mcc-gc-ims
#18
Carl Taylor, Fraser Lough, Stephen P Stanforth, Edward C Schwalbe, Ian A Fowlis, John R Dean
Listeria monocytogenes is a Gram-positive bacterium and an opportunistic food-borne pathogen which poses significant risk to the immune-compromised and pregnant due to the increased likelihood of acquiring infection and potential transmission of infection to the unborn child. Conventional methods of analysis suffer from either long turn-around times or lack the ability to discriminate between Listeria spp. reliably. This paper investigates an alternative method of detecting Listeria spp. using two novel enzyme substrates that liberate exogenous volatile organic compounds in the presence of α-mannosidase and D-alanyl aminopeptidase...
May 8, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28484776/isomerisation-of-an-intramolecular-hydrogen-bonded-photoswitch-protonated-azobis-2-imidazole
#19
James N Bull, Michael S Scholz, Neville J A Coughlan, Evan J Bieske
Photoisomerisation of protonated azobis(2-imidazole), an intramolecular hydrogen-bonded azoheteroarene photoswitch molecule, is investigated in the gas phase using tandem ion mobility mass spectrometry. The E and Z isomers exhibit distinct spectral responses, with E-Z photoisomerisation occurring over the 360-520 nm range (peak at 460 nm), and Z-E photoisomerisation taking place over the 320-420 nm range (peak at 390 nm). A minor photodissociation channel involving loss of N2 is observed for the E-isomer with a maximum efficiency at 390 nm, blue-shifted by ≈70 nm relative to the wavelength for maximum photoisomerisation response...
May 9, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28484399/biochemical-benefits-diagnosis-and-clinical-risks-evaluation-of-kratom
#20
REVIEW
Dimy Fluyau, Neelambika Revadigar
BACKGROUND: Kratom (Mitragyna speciosa) is a tropical tree with a long history of traditional use in parts of Africa and Southeast Asia. Kratom is also known as Thom, Thang, and Biak. Its leaves and the teas brewed from them have long been used by people in that region to manage pain and opioid withdrawal and to stave off fatigue. Kratom is actually consumed throughout the world for its stimulant effects and as an opioid substitute (in form of tea, chewed, smoked, or ingested in capsules)...
2017: Frontiers in Psychiatry
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