3,345 results match your criteria Journal of Mass Spectrometry[Journal]


Comparison of the fragmentation behavior of DNA and LNA single strands and duplexes.

J Mass Spectrom 2019 Feb 16. Epub 2019 Feb 16.

Department of Chemistry, Humboldt-Universitaet zu Berlin, Berlin, Germany.

DNA and locked nucleic acid (LNA) were characterized as single strands, as well as double stranded DNA-DNA duplexes and DNA-LNA hybrids using tandem mass spectrometry with collision-induced dissociation. Additionally, ion mobility spectrometry was carried out on selected species. Oligonucleotide duplexes of different sequences - bearing mismatch positions and abasic sites of complementary DNA 15-mers - were investigated to unravel general trends in their stability in the gas phase. Read More

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http://dx.doi.org/10.1002/jms.4344DOI Listing
February 2019

Reactivity of 4-thiothymidine with Fenton's reagent investigated by UV-Visible Spectroscopy and ElectroSpray Ionization Mass Spectrometry.

J Mass Spectrom 2019 Feb 15. Epub 2019 Feb 15.

Dipartimento di Chimica, Università degli Studi di Bari "Aldo Moro", Via Orabona, 4-70126, Bari, Italy.

The reactivity of the sulfur-containing nucleoside 4-thio-(2'-deoxy)-thymidine (S -TdR) under Fenton conditions, i.e. in the presence of H O and catalytic amounts of Fe (II), was investigated by UV-Vis spectroscopy and ElectroSpray Ionization Single and Tandem Mass Spectrometry (ESI-MS and MS/MS). Read More

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http://dx.doi.org/10.1002/jms.4343DOI Listing
February 2019
1 Read

Fabrication of homogenous three-dimensional biomimetic tissue for mass spectrometry imaging.

J Mass Spectrom 2019 Feb 11. Epub 2019 Feb 11.

State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China.

Reference samples are essential for mass spectrometric method optimization, data quality control, and target analyte quantitation. However, it is highly challenging to prepare an ideal homogeneous, standard-spiked tissue sample for mass spectrometry imaging (MSI) research. Herein, we present a standard-spiked 3D biomimetic tissue model fabricated with native cells, homogenate matrix, and biocompatible polymer. Read More

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http://dx.doi.org/10.1002/jms.4342DOI Listing
February 2019

Effects of aprotic solvents on the stability of metal-free superoxide dismutase probed by native electrospray ionization-ion mobility-mass spectrometry.

J Mass Spectrom 2019 Feb 8. Epub 2019 Feb 8.

National Center of Mass Spectrometry in Changchun & Jilin Province Key Laboratory of Chinese Medicine Chemistry and Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China.

Considering aprotic solvents are often used as cosolvents in investigating the interactions between small molecules and proteins, we assessed the effects of five aprotic solvents represented by dimethyl-formamide (DMF) on the structure stabilities of metal-free SOD1 (apo-SOD1) by native electrospray ionization-ion mobility-mass spectrometry (ESI-IM-MS). These aprotic solvents include DMF, 1,3-dimethyl-2-imidazolidinone (DMI), dimethyl-sulfoxide (DMSO), acetonitrile (ACN) and tetrahydrofuran (THF). Results indicated that DMI, DMSO and DMF at low percentage concentration could reduce the average charge and the dimer dissociation of apo-SOD1. Read More

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http://dx.doi.org/10.1002/jms.4341DOI Listing
February 2019

The pre-separation of oxygen containing compounds in oxidised heavy paraffinic fractions and their identification by GC-MS with Supersonic Molecular Beams.

J Mass Spectrom 2019 Feb 5. Epub 2019 Feb 5.

School of Chemistry, Tel Aviv University, Tel Aviv, 69978, Israel.

The heavy petroleum fractions produced during refining processes need to be upgraded to useable products to increase their value. Hydrogenated heavy paraffinic fractions can be oxidised to produce high value products that contain a variety of oxygenates. These heavy oxygenated paraffinic fractions need to be characterised to enable the control of oxidation processes and to understand product properties. Read More

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http://dx.doi.org/10.1002/jms.4340DOI Listing
February 2019

Top-down characterization of mouse core histones.

J Mass Spectrom 2019 Jan 30. Epub 2019 Jan 30.

School of Chemical Science & Engineering and Shanghai Key Laboratory of Chemical Assessment and Sustainability, Tongji University, Shanghai, 200092, China.

Histone post-translational modifications (PTMs) play various roles in chromatin-related cellular processes, and comprehensive analysis of these combinatorial PTMs at the intact protein level by top-down proteomics is the method of choice to reveal their crosstalk and biological functions. Here we report our top-down characterization of the core histones from mouse fibroblasts cells NIH/3T3, which is a classic model used in many kinds of research. With nanoRPLC-MS/MS analysis and ProteinGoggle database search, 547 protein species were identified with spectrum-level FDR ≤ 1%, where PTMs in 51 protein species were unambiguously localized with PTM scores ≥ 1. Read More

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http://dx.doi.org/10.1002/jms.4339DOI Listing
January 2019

Intellectual Property - The Foundation of Innovation.

J Mass Spectrom 2019 Jan 24. Epub 2019 Jan 24.

Current Address: Target Discovery, Inc., 4030 Fabian Way, Palo Alto, CA, 94303-4607.

Increasingly, the activities of the practicing scientist inextricably intersect with the business world. Science is central to the development and delivery of many goods or services, and scientific discovery can directly, or indirectly, lead to substantial revenue generation. Scientists, however, have little training in the complex issues of Intellectual Property (IP), and often little understanding of their rights and obligations. Read More

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http://dx.doi.org/10.1002/jms.4331DOI Listing
January 2019
1 Read

Deep-ultraviolet Laser Ablation Electrospray Ionization Mass Spectrometry.

J Mass Spectrom 2019 Jan 24. Epub 2019 Jan 24.

Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana, 70803, USA.

A 193 nm wavelength deep ultraviolet laser was used for ambient laser ablation electrospray ionization mass spectrometry of biological samples. A pulsed ArF excimer laser was used to ablate solid samples and the resulting plume of desorbed material merged with charged electrospray droplets to form ions that were detected with a quadrupole time-of-flight mass spectrometer. Solutions containing peptide and protein standards up to 66 kDa molecular weight were deposited on a metal target, dried, and analyzed. Read More

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http://dx.doi.org/10.1002/jms.4338DOI Listing
January 2019

Is the placental proteome impaired in well-controlled gestational diabetes?

J Mass Spectrom 2019 Jan 24. Epub 2019 Jan 24.

Department of Medicine - DIMED, University of Padova, Italy.

In pregnancy complicated by gestational diabetes (GDM), the human placenta shows several pathological functional and structural changes, but the extent to which maternal glycemic control contributes to placental abnormalities remains unclear. The aim of this study was to profile and compare the proteome of placentas from healthy pregnant women and those with GDM, to investigate the placenta-specific protein composition and possible changes of its function in presence of GDM. Quantitative proteomic analysis, based on LC-MS approach, revealed that higher (~15% increase) levels of galectin 1 and collagen alpha-1 XIV chain (although the difference regarding the latter was at the limit of significance) were present in GDM samples, while heat shock 70 kDa protein 1A/1B was less abundant in GDM placental tissue. Read More

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http://dx.doi.org/10.1002/jms.4336DOI Listing
January 2019
1 Read

Comparison of ESI-MS/MS and APCI-MS methods for the quantification of folic acid analogs in C. elegans.

J Mass Spectrom 2019 Jan 24. Epub 2019 Jan 24.

Max Planck Institute for Biology of Ageing, Cologne, Germany.

Folic acid (FA) plays a vital role in central metabolism, including the one carbon cycle, nucleotide and amino acid biosynthesis. The development of sensitive, accurate analytical methods to measure FA intermediates in tissues is critical to understand their biological roles in diverse physiological and pathological contexts. Here, we developed a highly sensitive method for the simultaneous quantification of FA intermediates in the nematode C. Read More

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http://doi.wiley.com/10.1002/jms.4337
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http://dx.doi.org/10.1002/jms.4337DOI Listing
January 2019
6 Reads

Combining MALDI-2 and Transmission Geometry Laser Optics to Achieve High Sensitivity for Ultra-High Spatial Resolution Surface Analysis.

J Mass Spectrom 2019 Jan 24. Epub 2019 Jan 24.

Mass Spectrometry Research Center, Vanderbilt University, 465 21st Ave S #9160, Nashville, TN, 37235, USA.

A transmission geometry optical configuration allows for smaller laser spot size to facilitate high resolution MALDI mass spectrometry. This increase in spatial resolution (i.e. Read More

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http://doi.wiley.com/10.1002/jms.4335
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http://dx.doi.org/10.1002/jms.4335DOI Listing
January 2019
4 Reads

Quantification of enantiomers by mass spectrometry based on chemical derivatization and spectral shape deformation quantitative theory.

J Mass Spectrom 2019 Jan 22. Epub 2019 Jan 22.

State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan, 410082, PR China.

A facile mass spectrometric kinetic method for quantitative analysis of chiral compounds was developed by integrating mass spectrometry based on chemical derivatization and the spectral shape deformation quantitative theory. Chemical derivatization was employed to introduce diastereomeric environments to the chrial compounds of interest, resulting in different abundance distribution patterns of fragment ions of the derivatization products of enantiomers in mass spectrometry. The quantitative information of the chrial compounds of interest was extracted from complex mass spectral data by an advanced calibration model derived based on the spectral shape deformation quantitative theory. Read More

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http://dx.doi.org/10.1002/jms.4334DOI Listing
January 2019
1 Read
2.379 Impact Factor

Ion manipulation and enrichment mass spectrometer for cleavage of disulfide bond via ion/ion reaction.

J Mass Spectrom 2019 Jan 22. Epub 2019 Jan 22.

Division of Chemical Metrology and Analytical Science, National Institute of Metrology, Beijing, 100029, P. R. China.

A novel mass spectrometer with the capability of ion manipulation and enrichment was developed to perform gas-phase ion/ion reactions followed by product ions accumulation. The development of this apparatus opens opportunities for more complex sequences of ion manipulations, thus offers the potential on extensive application involving ion/ion reaction. Here, cleavage of disulfide bond in peptide was demonstrated based upon this ion manipulation and enrichment mass spectrometer. Read More

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http://dx.doi.org/10.1002/jms.4333DOI Listing
January 2019

Identification of G-nerve agents at picogram levels from complex organic samples containing hydrocarbon interferences by aqueous extraction, followed by derivatization and liquid chromatography-mass spectrometry analysis.

J Mass Spectrom 2019 Jan 21. Epub 2019 Jan 21.

Department of Analytical Chemistry, Israel Institute for Biological Research (IIBR) P.O.B. 19, Ness Ziona, ISRAEL.

The chromatograms obtained from the gas chromatography-electron ionization mass spectrometric (GC-EI-MS) analysis of extracts containing G-nerve agents in the presence of diesel, gasoline, etc., are dominated by hydrocarbon backgrounds that "mask" the G-nerve agents, leading to severe difficulties in identification. This paper presents a practical solution for this challenge by transferring the G-nerve agents from the organic phase into the aqueous phase using liquid-liquid extraction (LLE), followed by derivatization with 2-[(dimethylamino)methyl]phenol (2-DMAMP), allowing ultrasensitive LC-ESI-MS/MS analysis of the G-derivatives. Read More

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http://dx.doi.org/10.1002/jms.4332DOI Listing
January 2019
1 Read

Hydralazine derivative of aldehyde: A new type of [M-H] ion formed in electrospray ionization mass spectrometry.

J Mass Spectrom 2019 Jan 16. Epub 2019 Jan 16.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan, 430072, People's Republic of China.

Hydralazine has been widely employed in the development of drugs, derivatization reagents and ligands. In the present work, we reported a new type of dehydrogenated ion [M-H] that was produced from the hydralazine derivative of hexanal in electrospray ionization mass spectrometry (ESI-MS). The formation of [M-H] ions in the ESI-MS was found to be independent on the mobile phase composition of the liquid chromatography and ESI source parameters. Read More

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http://dx.doi.org/10.1002/jms.4330DOI Listing
January 2019
2.379 Impact Factor

Dissociation pathways of protic ionic liquid clusters: Alkylammonium nitrates.

J Mass Spectrom 2019 Jan 16. Epub 2019 Jan 16.

Space Vehicles Directorate, Air Force Research Laboratory, Kirtland AFB, New Mexico, United States, 87117.

Protic ionic liquids are promising candidates for many applications, including as spacecraft propellants. For both fundamental interest and understanding clustering and dissociation during electrospray-based propulsion, it is useful to explore the dissociation pathways of protic ionic liquid clusters, as well as the factors affecting the relative contributions of each pathway to the observed MS/MS spectra. With that said, most of the published reports on ionic liquid cluster dissociation have focused on aprotic ionic liquids. Read More

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http://dx.doi.org/10.1002/jms.4329DOI Listing
January 2019

Improved Online Hydrogen Isotope Analysis of Halite Aqueous Inclusions.

J Mass Spectrom 2019 Jan 4. Epub 2019 Jan 4.

Elementar Analysensysteme GmbH - Elementar, Straße 1, 63505, Langenselbold, Germany.

We demonstrate an improved method based on Continuous Flow Elemental Analyser PYrolysis Isotopic Ratio Mass Spectrometry (CF-EA-PY-IRMS) to measure the H/ H ratios of water trapped in halite crystals. Two challenges to overcome are the low hydrogen concentration of samples (10 to 50 μmoles H .g ) and the high chloride concentration released when reacting halite in an elemental analyser. Read More

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http://dx.doi.org/10.1002/jms.4323DOI Listing
January 2019

Study of the cyanoacrylate fuming mechanism by matrix assister laser desorption/ionization mass spectrometry.

J Mass Spectrom 2019 Jan 2. Epub 2019 Jan 2.

Department of Chemistry, Iowa State University, Ames, IA, 50011.

Despite cyanoacrylate fuming being widely used in the forensic science field, its mechanism is not well understood. In this study, matrix assisted laser desorption/ionization (MALDI) mass spectrometry is used to study latent fingerprints that have been cyanoacrylate fumed in an attempt to gain insight into the fuming mechanism. In the negative mode mass spectrometry data, four compounds related to the polymerization of cyanoacrylate are identified and their structures are determined from accurate mass and MS/MS. Read More

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http://dx.doi.org/10.1002/jms.4325DOI Listing
January 2019
1 Read

Signal enhancement in laser diode thermal desorption-triple quadrupole mass spectrometry analysis using microwell surface coatings.

J Mass Spectrom 2019 Jan 2. Epub 2019 Jan 2.

Department of Chemistry, Université de Sherbrooke, Sherbrooke, QC, J1K 2R1.

Laser diode thermal desorption (LDTD) is an ionization source usually coupled to triple quadrupole mass spectrometry (QqQMS) and specifically designed for laboratories requiring high-throughput analysis. It has been observed that surface coatings on LDTD microwell plates can improve the sensitivity of the analysis of small polar molecules. The objective of the present study is to understand and quantify the effect of microwell surface coatings on signal intensity of small organic molecules of clinical, environmental and forensic interest. Read More

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http://dx.doi.org/10.1002/jms.4328DOI Listing
January 2019
1 Read

High-throughput polymer tip-electrospray ionization mass spectrometry for enhanced detection of neopterin and biopterin in clinical urine samples.

J Mass Spectrom 2018 Dec 29. Epub 2018 Dec 29.

Jiangxi Provincial Maternal and Child Health Hospital, Nanchang, 330006, China.

Urinary biopterin (Bio) and neopterin (Neo) are important markers for clinical diagnosis of hyperphenylalaninemia. Herein, we developed a high-throughput analysis method based on electrospray ionization mass spectrometry (ESI-MS) with polymer tips for the rapid quantitative detection of Bio and Neo in clinical urine samples. Different polymer tips were investigated. Read More

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http://doi.wiley.com/10.1002/jms.4322
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http://dx.doi.org/10.1002/jms.4322DOI Listing
December 2018
16 Reads

Challenges in the identification process of phenidate analogues in LC-ESI-MS/MS analysis: Information enhancement by derivatization with isobutyl chloroformate.

J Mass Spectrom 2018 Dec 29. Epub 2018 Dec 29.

Department of Analytical Chemistry, Israel Institute for Biological Research (IIBR), Ness Ziona, Israel.

A new analytical technique for the structural elucidation of four representative phenidate analogues possessing a secondary amine residue, which leads to a major/single amine-representative fragment/product ion at m/z 84 both in their GC-EI-MS and LC-ESI-MS/MS spectra, making their identification ambiguous, was developed. The method is based on "in vial" chemical derivatization with isobutyl chloroformate in both aqueous and organic solutions, followed by liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS/MS). The resulting carbamate derivatives promote rich fragmentation patterns with full coverage of all substructures of the molecule, enabling detailed structural elucidation and unambiguous identification of the original compounds at low ng/ml levels. Read More

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http://doi.wiley.com/10.1002/jms.4327
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http://dx.doi.org/10.1002/jms.4327DOI Listing
December 2018
2 Reads

Electrospray multistage mass spectrometry in the negative ion mode for the unambiguous molecular and structural characterization of acidic hydrolysates from 4-O-methylglucuronoxylan generated by endoxylanases.

J Mass Spectrom 2018 Dec 29. Epub 2018 Dec 29.

Bioconversion Group, Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashi-Hiroshima, Hiroshima, 739-0046, Japan.

A rapid analytical methodology is proposed to answer the two questions about the molecular and structural features of the acidic xylo-oligosaccharides (XOS) formed upon the enzymatic hydrolysis of 4-O-methylglucuronoxylan. The shortest acidic XOS carrying a methylglucuronic acid moiety and the possible distribution of larger products (molecular feature) are instantly found by ESI-MS in the negative ion mode which filters the unwanted neutral XOS. The acidic moiety is then unambiguously positioned along the xylose backbone (structural feature) by ESI-MS in the negative ion mode via the selection /activation/dissociation of the product ions formed upon the one-way and stepwise glycosidic bond cleavage at the reducing end. Read More

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http://dx.doi.org/10.1002/jms.4321DOI Listing
December 2018
2 Reads

LC-DAD-ESI-MS/MS-based phenolic profiling and antioxidant activity in Turkish cv. Nizip Yaglik olive oils from different maturity olives.

J Mass Spectrom 2018 Dec 28. Epub 2018 Dec 28.

Department of Biotechnology, Institute of Natural and Applied Sciences, Cukurova University, 01330, Adana, Turkey.

The current study was designed to find out how olive maturity indices (MI: 2.5, 3.5 and 4. Read More

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http://doi.wiley.com/10.1002/jms.4326
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http://dx.doi.org/10.1002/jms.4326DOI Listing
December 2018
10 Reads
2.379 Impact Factor

MALDI- and LDI-MS saponin fingerprint of leaves and sticks components of commercial yerba mate (Ilex paraguariensis).

J Mass Spectrom 2018 Dec 26. Epub 2018 Dec 26.

Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica. Pabellón II, 3er P., Ciudad Universitaria, 1428, Buenos Aires, Argentina.

Yerba mate (YM) is massively produced and consumed as an infusion in South America and spreading all over the world. This product is obtained from dried leaves of Ilex paraguariensis Saint Hilaire, mixed with fragments of dried branches (sticks). For its commercialization YM must have a minimum percentage of leaves because its presence determines YMs quality and price. Read More

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http://doi.wiley.com/10.1002/jms.4324
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http://dx.doi.org/10.1002/jms.4324DOI Listing
December 2018
5 Reads

A high-throughput glutathione trapping assay with combined high sensitivity and specificity in high resolution mass spectrometry by applying product ion extraction and data-dependent neutral loss.

J Mass Spectrom 2018 Dec 10. Epub 2018 Dec 10.

Department of Drug Metabolism and Pharmacokinetics, Sanofi, 153 2nd Avenue, Waltham, MA, 02451, USA.

Reactive metabolites are thought to play a pivotal role in the pathogenesis of some drug induced liver injury (DILI) and idiosyncratic adverse drug reactions (IADRs), which is of concern to patient safety and has been a cause of drugs being withdrawn from the market place. To identify drugs with a lower propensity for causing DILI and /or IADRs, high-throughput assays to capture reactive metabolites are required in pharmaceutical industry for early drug discovery risk assessment. We describe the development of an assay to detect glutathione adducts with combined high sensitivity, enhanced specificity and rapid data analysis. Read More

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http://dx.doi.org/10.1002/jms.4320DOI Listing
December 2018
7 Reads

Compositional elucidation of heavy petroleum base oil by GC×GC-EI/PI/CI/FI-TOFMS.

J Mass Spectrom 2018 Dec 7. Epub 2018 Dec 7.

University of Liège, Department of Chemistry, Organic & Biological Analytical Chemistry Group, Allée du 6 aout, B6c, B-4000, Liège (Sart Tilman), Belgium.

Comprehensive two-dimensional gas chromatography (GC×GC) coupled to time-of-flight mass spectrometry is a powerful separation tool for complex petroleum product analysis. However, the most commonly used electron ionization (EI) technique often makes the identification of the majority of hydrocarbons impossible due to the exhaustive fragmentation and lack of molecular ion preservation, prompting the need of soft-ionization energies. In this study, three different soft-ionization techniques including photo ionization (PI), chemical ionization (CI), and field ionization (FI) were compared against EI to elucidate their relative capabilities to reveal different base oil hydrocarbon classes. Read More

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http://dx.doi.org/10.1002/jms.4319DOI Listing
December 2018
1 Read

Reagent-free and pH-independent Degradation of N-nitrosamines Using Electrons Generated via Corona Discharge at Ambient Pressure.

J Mass Spectrom 2018 Dec 7. Epub 2018 Dec 7.

Hefei National Laboratory for Physical Sciences at the Microscale, School of Chemistry and Materials Science, University of Science and Technology of China (USTC), Hefei, 230026, P. R. China.

Traditional degradation methods for N-nitrosamines are either confined with acid solution or required for additional chemical reagents to guarantee high reaction efficiency. Herein, we demonstrate a facile and effective way for reagent-free and pH-independent degradation of N-nitrosamines, which was induced by free electrons generated via corona discharge at ambient pressure. The highly reactive free electron is produced in situ and responsible for degradation of three N-nitrosamines, which was also theoretically confirmed. Read More

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http://dx.doi.org/10.1002/jms.4318DOI Listing
December 2018
1 Read

How to avoid interfering electrochemical reactions in ESI-MS analysis.

J Mass Spectrom 2018 Dec 3. Epub 2018 Dec 3.

Institute of Particle Technology, FAU Erlangen-Nurnberg, Germany.

The presence of electrochemical reactions occurring in an electrospray processes at the point where the current enters the liquid is discussed since the early 1990’s. This current transfer to the liquid requires in general oxidation or reduction of either electrolyte species in the liquid sprayed or of the electrode material in contact with the liquid. As a result new chemical species are generated. Read More

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http://doi.wiley.com/10.1002/jms.4315
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http://dx.doi.org/10.1002/jms.4315DOI Listing
December 2018
7 Reads

Volatile compounds profiling by using proton transfer reaction-time of flight-mass spectrometry (PTR-ToF-MS). The case study of dark chocolates organoleptic differences.

J Mass Spectrom 2019 Jan;54(1):92-119

Centre des Sciences du Goût et de l'Alimentation (CSGA), AgroSup Dijon, CNRS, INRA, Université Bourgogne Franche-Comté, F-21000, Dijon, France.

Direct-injection mass spectrometry (DIMS) techniques have evolved into powerful methods to analyse volatile organic compounds (VOCs) without the need of chromatographic separation. Combined to chemometrics, they have been used in many domains to solve sample categorization issues based on volatilome determination. In this paper, different DIMS methods that have largely outperformed conventional electronic noses (e-noses) in classification tasks are briefly reviewed, with an emphasis on food-related applications. Read More

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http://dx.doi.org/10.1002/jms.4317DOI Listing
January 2019
4 Reads

Energy-resolved mass spectrometry for differentiation of the fluorine substitution position on the phenyl ring of fluoromethcathinones.

J Mass Spectrom 2018 Nov 24. Epub 2018 Nov 24.

Institute of Science and Engineering, Kanazawa University, Kanazawa, Japan.

A reliable method for structural analysis is crucial for the forensic investigation of new psychoactive substances (NPSs). Towards this end, mass spectrometry is one of the most efficient and facile methods for the identification of NPSs. However, the differentiation among 2-, 3-, and 4-fluoromethcathinones (o-, m-, and p-FMCs), which are ring-fluorinated positional isomers part of the major class of NPSs referred to as synthetic cathinones, remains a challenge. Read More

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http://doi.wiley.com/10.1002/jms.4316
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http://dx.doi.org/10.1002/jms.4316DOI Listing
November 2018
2 Reads

Newborn screening for 3-hydroxy-3-methylglutaric aciduria using direct analysis in real-time mass spectrometry.

J Mass Spectrom 2018 Nov 23. Epub 2018 Nov 23.

National Center for Food Safety Risk Assessment Application Technology Cooperation Center, Yangtze Delta Region Institute of Tsinghua University, Jiaxing, 314006, China.

A novel method utilizing ambient thermal desorption ionization with a direct analysis in real-time source integrated with mass spectrometry (DART-MS) was established and applied to the rapid analysis of 3-hydroxy-3-methylglutaric (3-HMG) acid in the neonatal urine. Instrument parameter settings were optimized to obtain high sensitive and accurate determination of 3-HMG acid. The use of helium gas heated to temperature of 400 C was observed to permit deprotonation, 3-HMG acid producing a abundant [M-H] (m/z 161) in the negative ion mode. Read More

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http://dx.doi.org/10.1002/jms.4314DOI Listing
November 2018

Substitution reactions of gaseous ions in a three-dimensional quadrupole ion trap.

J Mass Spectrom 2019 Jan;54(1):81-87

Institut für Organische und Biomolekulare Chemie, Universität Göttingen, Tammannstraße 2, 37077, Göttingen, Germany.

Substitution reactions between gaseous ions and neutral substrate molecules are of ongoing high interest. To investigate these processes in a qualitative and quantitative manner, we have constructed a device, with which a defined amount of a volatile substrate can be mixed with a defined amount of helium gas and added into a three-dimensional quadrupole ion trap. From the known inner volume of the device, the known ratio n :n of the mixture, and the determined absolute partial pressure of helium in the ion trap, we can derive the partial pressure of the substrate in the ion trap and, thus, convert the directly observable pseudo-first-order rate constants of the substitution reactions into absolute bimolecular rate constants. Read More

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http://dx.doi.org/10.1002/jms.4313DOI Listing
January 2019

Geographical traceability of wheat and its products using multielement light stable Isotopes coupled with chemometrics.

J Mass Spectrom 2018 Nov 15. Epub 2018 Nov 15.

Institute of Food Science and Technology, Key Laboratory of Agro-Products Processing, CAAS/, Ministry of Agriculture, Beijing, 100193, PR China.

The present study was aimed to investigate the variation of stable isotopic ratios of carbon, nitrogen, hydrogen, and oxygen in wheat kernel along with different processed fractions from three geographical origins across five years using isotope ratio mass spectrometry (IRMS). Multiway ANOVA revealed significant differences among region, harvest year, processing and their interactions for all isotopes. The region contributed the major variability in the δ C ‰, δ H ‰, δ N ‰, and δ O‰ values of wheat. Read More

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http://doi.wiley.com/10.1002/jms.4312
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http://dx.doi.org/10.1002/jms.4312DOI Listing
November 2018
10 Reads

Energetic switch of the proline effect in collision-induced dissociation of singly and doubly protonated peptide Ala-Ala-Arg-Pro-Ala-Ala.

J Mass Spectrom 2019 Jan;54(1):55-65

College of Chemistry, Beijing Normal University, Beijing, China.

Suppression of the selective cleavage at N-terminal of proline is observed in the peptide cleavage by proteolytic enzyme trypsin and in the fragment ion mass spectra of peptides containing Arg-Pro sequence. An insight into the fragmentation mechanism of the influence of arginine residue on the proline effect can help in prediction of mass spectra and in protein structure analysis. In this work, collision-induced dissociation spectra of singly and doubly charged peptide AARPAA were studied by ESI MS/MS and theoretical calculation methods. Read More

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http://doi.wiley.com/10.1002/jms.4311
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http://dx.doi.org/10.1002/jms.4311DOI Listing
January 2019
9 Reads

Electrostatic field-induced tip-electrospray ionization mass spectrometry for direct analysis of raw food materials.

Authors:
Lei Li Wen Li Bin Hu

J Mass Spectrom 2019 Jan;54(1):73-80

Institute of Mass Spectrometer and Atmospheric Environment, Guangdong Provincial Engineering Research Center for On-line Source Apportionment System of Air Pollution, Jinan University, Guangzhou, 510632, China.

Rapid characterization of metabolites and risk compounds such as chemical residues and natural toxins in raw food materials such as vegetables, meats, and edible living plants and animals plays an important part in ensuing food quality and safety. To rapidly characterize the analytes in raw food materials, it is essential to develop in situ method for directly analyzing raw food materials. In this work, raw food materials including biological tissues and living samples were placed between an electrode and mass spectrometric (MS) inlet under a strong electrostatic field; analytes were rapidly induced to generate electrospray ionization (ESI) from the sample tip by adding a drop of solvent onto the sample. Read More

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http://dx.doi.org/10.1002/jms.4309DOI Listing
January 2019
3 Reads
2.379 Impact Factor

Gas phase hydration of polyethylene glycol-metal cation complexes.

Authors:
Rafał Frański

J Mass Spectrom 2019 Jan;54(1):88-91

Faculty of Chemistry, Adam Mickiewicz University, Poznań, Poland.

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http://dx.doi.org/10.1002/jms.4310DOI Listing
January 2019
2 Reads

Phytochemical analysis of Ononis arvensis L. by liquid chromatography coupled with mass spectrometry.

J Mass Spectrom 2018 Nov 8. Epub 2018 Nov 8.

Department of Pharmacognosy, Semmelweis University, Üllői út 26, Budapest, 1085, Hungary.

Ononis arvensis L. can be found overall in Europe and is used to treat infections of the urinary tract and skin diseases in ethnopharmacology. Flavonoids, hydroxycinnamic acids, oxycoumarin scopoletin and scopolin, phytosterols, lectins and some selected isoflavonoids were identified in O. Read More

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http://doi.wiley.com/10.1002/jms.4308
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http://dx.doi.org/10.1002/jms.4308DOI Listing
November 2018
11 Reads

Ultrasonication-assisted spray ionization-based micro-reactors for online monitoring of fast chemical reactions by mass spectrometry.

J Mass Spectrom 2019 Jan;54(1):26-34

Department of Applied Chemistry, National Chiao Tung University, Hsinchu, 300, Taiwan.

Microfluidics can be used to handle relatively small volumes of samples and to conduct reactions in microliter-sized volumes. Electrospray ionization can couple microfluidics with mass spectrometry (MS) to monitor chemical reactions online. However, fabricating microfluidic chips is time-consuming. Read More

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http://doi.wiley.com/10.1002/jms.4307
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http://dx.doi.org/10.1002/jms.4307DOI Listing
January 2019
10 Reads

Gas phase reaction between chromones and solvent in an electrospray ionization source.

J Mass Spectrom 2019 Jan;54(1):66-72

Department of Chemistry and Chemical Engineering, Beijing University of Technology, Beijing, China.

Chromones were measured by using electrospray ionization mass spectrometry in negative mode. Interestingly, in addition to the deprotonated ion ([M - H] ), unexpected [M + 17] and [M + 31] ions were observed in high intensity when water and methanol were used as the solvent. Chromones with different substitutes were tested. Read More

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http://dx.doi.org/10.1002/jms.4305DOI Listing
January 2019
1 Read

High-resolution GC/MS studies of a light crude oil fraction.

J Mass Spectrom 2019 Jan;54(1):47-54

Max-Planck Institut für Kohlenforschung, Mass Spectrometry Group, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany.

The continuous development in analytical instrumentation has brought the newly developed Orbitrap-based gas chromatography / mass spectrometry (GC/MS) instrument into the forefront for the analysis of complex mixtures such as crude oil. Traditional instrumentation usually requires a choice to be made between mass resolving power or an efficient chromatographic separation, which ideally enables the distinction of structural isomers that is not possible by mass spectrometry alone. Now, these features can be combined, thus enabling a deeper understanding of the constituents of volatile samples on a molecular level. Read More

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http://dx.doi.org/10.1002/jms.4306DOI Listing
January 2019
2 Reads

Gas-phase fragmentation reactions of protonated benzofuran- and dihydrobenzofuran-type neolignans investigated by accurate-mass electrospray ionization tandem mass spectrometry.

J Mass Spectrom 2019 Jan;54(1):35-46

Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil.

We have investigated gas-phase fragmentation reactions of protonated benzofuran neolignans (BNs) and dihydrobenzofuran neolignans (DBNs) by accurate-mass electrospray ionization tandem and multiple-stage (MS ) mass spectrometry combined with thermochemical data estimated by Computational Chemistry. Most of the protonated compounds fragment into product ions B ([M + H-MeOH] ), C ([B-MeOH] ), D ([C-CO] ), and E ([D-CO] ) upon collision-induced dissociation (CID). However, we identified a series of diagnostic ions and associated them with specific structural features. Read More

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http://dx.doi.org/10.1002/jms.4304DOI Listing
January 2019
1 Read

Top-down analysis of novel synthetic branched proteins.

J Mass Spectrom 2019 Jan;54(1):19-25

Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20742, USA.

A strategy for top-down analysis of branched proteins has been reported earlier, which relies on electron transfer dissociation assisted by collisional activation, and software designed for graphic interpretation of tandem mass spectra and adapted for branched proteins. In the present study, the strategy is applied to identify unknown and novel products of reactions in which rationally mutated proteoforms of Rub1 are used to probe the selectivity of E1 and E2 enzymes normally active in ubiquitination. To test and demonstrate this application, components and attachment sites of three branched dimers are deduced and the mutations are confirmed. Read More

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http://dx.doi.org/10.1002/jms.4303DOI Listing
January 2019
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Comprehensive lipid profiling of early stage oocytes and embryos by MRM profiling.

J Mass Spectrom 2018 Dec;53(12):1247-1252

Center for Analytical Instrumentation Development, Department of Chemistry, Purdue University, West Lafayette, Indiana.

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http://doi.wiley.com/10.1002/jms.4301
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http://dx.doi.org/10.1002/jms.4301DOI Listing
December 2018
8 Reads

Isolation and characterization of kurstakin and surfactin isoforms produced by Enterobacter cloacae C3 strain.

J Mass Spectrom 2019 Jan;54(1):7-18

Laboratoire de Génie Enzymatique et de Microbiologie, Université de Sfax, Ecole Nationale d'Ingénieurs de Sfax, Sfax, Tunisia.

In this work, the extraction, structural analysis, and identification as well as antimicrobial, anti-adhesive, and antibiofilm activities of lipopeptides produced by Enterobacter cloacae C3 strain were studied. A combination of chromatographic and spectroscopic techniques offers opportunities for a better characterization of the biosurfactant structure. Thin layer chromatography (TLC) and HPLC for amino acid composition determination are used. Read More

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http://doi.wiley.com/10.1002/jms.4302
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http://dx.doi.org/10.1002/jms.4302DOI Listing
January 2019
25 Reads

Multivariate calibration method for mass spectrometry of interfering gases such as mixtures of CO, N , and CO.

J Mass Spectrom 2018 Dec;53(12):1214-1221

Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland.

A multivariate calibration method for mass spectrometry is presented that enables a quantitative analysis of gas mixtures containing interfering gases that contribute to the same mass-to-charge ratios at nominal resolution. Multiple calibration gas mixtures with linearly independent compositions are used in order to obtain the calibration constants for the contribution of each gas to each of the mass-to-charge ratio peaks. The method was successfully applied to the quantitative detection of CO in a mixture with CO and N , which represents a difficulty commonly encountered in heterogeneous catalysis and electrocatalysis research. Read More

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http://doi.wiley.com/10.1002/jms.4299
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http://dx.doi.org/10.1002/jms.4299DOI Listing
December 2018
2 Reads

Analyte-substrate interactions at functionalized tip electrospray ionization mass spectrometry: Molecular mechanisms and applications.

Authors:
Ya-Nan Yao Bin Hu

J Mass Spectrom 2018 Dec;53(12):1222-1229

Institute of Mass Spectrometer and Atmospheric Environment, Jinan University, Guangzhou, 510632, China.

Conventional electrospray ionization mass spectrometry (ESI-MS) commonly uses capillary tip for sample introduction and ionization. In recent years, ESI-MS using noncapillary substrate tips has attracted growing interest as it allows separation and enrichment of analytes from complex samples due to analytes-substrate interactions. In this work, model mixtures and functionalized tips were employed to investigate the molecular mechanism of the analyte-substrate interactions. Read More

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http://doi.wiley.com/10.1002/jms.4300
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http://dx.doi.org/10.1002/jms.4300DOI Listing
December 2018
12 Reads

Anthocyanidins structural study using positive electrospray ionization triple quadrupole mass spectrometry and H/D exchange.

J Mass Spectrom 2018 Dec;53(12):1230-1237

Fenn Mass Spectrometry Laboratory, Federal University of Parana (UFPR), Brazil.

We report herein a detailed structural study by collision-induced dissociation (CID) of nonglycosylated anthocyanins (anthocyanidins) using electrospray ionization triple quadrupole mass spectrometry (ESI-QqQ) and isotope labeling experiments to understand the fragmentation process often used in mass spectrometry analysis of this class of compounds. Tandem mass spectrometric product ion spectra for three anthocyanidins (cyanidin, delphynidin, and pelargonin) were evaluated to propose fragmentation mechanisms to this natural colorant class of organic compounds. The proposed rearrangements, retro Diels-Alder reaction, water loss, CO losses, and stable acylium ion formation, were evaluated based on tandem mass spectrometric experiments of normal and labeled precursor ions together to computational thermochemistry. Read More

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http://doi.wiley.com/10.1002/jms.4293
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http://dx.doi.org/10.1002/jms.4293DOI Listing
December 2018
5 Reads

w-Type ions formed by electron transfer dissociation of Cys-containing peptides investigated by infrared ion spectroscopy.

J Mass Spectrom 2018 Dec;53(12):1207-1213

Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Nijmegen, The Netherlands.

In mass spectrometry-based peptide sequencing, electron transfer dissociation (ETD) and electron capture dissociation (ECD) have become well-established fragmentation methods complementary to collision-induced dissociation. The dominant fragmentation pathways during ETD and ECD primarily involve the formation of c- and z -type ions by cleavage of the peptide backbone at the N─C bond, although neutral losses from amino acid side chains have also been observed. Residue-specific neutral side chain losses provide useful information when conducting database searching and de novo sequencing. Read More

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http://dx.doi.org/10.1002/jms.4298DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6283004PMC
December 2018
3 Reads

The use of chromium(III) complexes to enhance peptide protonation by electrospray ionization mass spectrometry.

J Mass Spectrom 2018 Dec;53(12):1198-1206

Department of Chemistry and Biochemistry, The University of Alabama, Tuscaloosa, Alabama.

The addition of trivalent chromium, Cr(III), reagents to peptide solutions can increase the intensity of doubly protonated peptides, [M + 2H] , through electrospray ionization (ESI). Three model heptapeptides were studied: neutral (AAAAAAA), acidic (AAEEEAA), and basic (AAAKAAA). The neutral and acidic peptides form almost no 2+ ions in the absence of Cr(III). Read More

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http://doi.wiley.com/10.1002/jms.4297
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http://dx.doi.org/10.1002/jms.4297DOI Listing
December 2018
3 Reads

Direct differentiation of stereoisomers of ezetimibe/ambrisentan/atorvastatin and their mechanism study by electrospray ionization quadrupole time-of-flight mass spectrometry.

J Mass Spectrom 2018 Dec;53(12):1238-1246

Institute of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Sciences, Hangzhou, PR China.

A mass spectrometric method is introduced for rapid and accurate chiral quantification by examining a trimeric metal complex into which a chiral reference is incorporated with the analyte. Several metal ions (Cu , Ni , Mg , Mn , Co , and Zn ) were selected as the central metal ion, and chiral drugs ezetimibe (EZM) and ambrisentan (AMB) were used as the reference to each other for isomeric differentiation by using electrospray ionization quadrupole time-of-flight mass spectrometry. Doubly charged trimeric cluster ions instead of the singly charged clusters were applied in this study. Read More

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http://dx.doi.org/10.1002/jms.4296DOI Listing
December 2018
8 Reads