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Rapid Communications in Mass Spectrometry: RCM

Justin G Coughlin, Zhongjie Yu, Emily M Elliott
RATIONALE: Nitrogen oxides or NOx (NOx  = NO + NO2 ) play an important role in air quality, atmospheric chemistry, and climate. The isotopic compositions of anthropogenic and natural NO2 sources are wide-ranging, and they can be used to constrain sources of ambient NO2 and associated atmospheric deposition of nitrogen compounds. While passive sample collection of NO2 isotopes has been used in field studies to determine NOx source influences on atmospheric deposition, this approach has not been evaluated for accuracy or precision under different environmental conditions...
April 20, 2017: Rapid Communications in Mass Spectrometry: RCM
Mary Hayden, Ruchika Bhawal, John Escobedo, Clinton Harmon, Todd O'Hara, David Klein, Susan San-Francisco, Masoud Zabet-Moghaddam, Céline A J Godard-Codding
RATIONALE: Analysis of steroids from precious blubber biopsies obtained from marine mammals, especially endangered species, can provide valuable information on their endocrine status. Challenges with currently used ELISA methodology include lack of absolute quantitation and incompatibility with multiple steroids analysis due to limited biopsy mass. Development of a sensitive, accurate analytical method for this purpose is critical. METHODS: A nanoLC/MS/MS method was validated for sensitive, specific and quantitative analysis of three steroid hormones, without derivatization, extracted from 50 mg blubber samples...
April 19, 2017: Rapid Communications in Mass Spectrometry: RCM
Lilan Wu, Yunshan Wu, Weiying Chen, Wen Zhou, Lipeng Tang, Ben Li, Bo Liu
RATIONALE: Artemisitene showed a wide variety of pharmacological activities, such as antioxidant protection in vitro and in vivo. It has been identified as a novel Nrf2 inducer. However, there is no report on an UPLC-MS/MS method to quantitate artemisitene in rat plasma and its application on pharmacokinetic profile study. METHODS: An ACQUITY UPLC(TM) BEH Symmetry ShieldRP18 column (1.7 µm, 2.1 mm × 100 mm) was used with a flow rate of 0.3 mL · min(-1) ...
April 12, 2017: Rapid Communications in Mass Spectrometry: RCM
Xinming Huo, Jin Chen, Fei Tang, Tongtong Yao, Shiyun Piao, Kai Ni, Xiaohao Wang
RATIONALE: Secular frequency scanning is a mass spectrometry (MS) analysis method in which the frequency of the auxiliary alternating current (AC) signal is scanned. It has low requirements for radio frequency (RF) power, which is beneficial for the miniaturization of the mass spectrometer. In this study, the MS performance in the reverse secular frequency scanning (RSFS) mode is optimized for a rectilinear ion trap (RIT), and a method for rapid MS analysis using continuous secular frequency scanning (CSFS) is proposed...
April 12, 2017: Rapid Communications in Mass Spectrometry: RCM
Chunhui Liu, Hongyan Si, Peilin Han, Mingsheng Tang
The geometries and stabilities of BeBn(+) (up to n = 8) clusters, have been systematically investigated by using the B3LYP and CCSD(T) method. All the possible geometrical structures of BeBn(+) clusters were optimized at B3LYP/6-311 + G(d) level. The single point energies of all the structures were computed at CCSD(T)/aug-cc-pVDZ level. The calculated results showed the most stable structures of the BeBn(+) clusters are planar; the B atoms tend to aggregate to form the boron ring and the Be atoms as coordination atoms are in the periphery of the clusters...
April 12, 2017: Rapid Communications in Mass Spectrometry: RCM
Tomasz Pieńkos, Stanisław Halas
RATIONALE: The goal of this research was to construct an effective gas ion source for isotope ratio mass spectrometry, which generates sufficiently strong and stable ion beams for multiple isotope ratio analysis of sulfur and oxygen from readily available gases such as SO2 , CO2 , CO, O2 and chlorine from CH3 Cl gas. METHODS: By means of a 60° sector mass spectrometer equipped with a new type of sensitive ion source and with a dual inlet system and triple collector assembly, we have measured (34) S/(32) S and challenging (36) S/(32) S isotope ratios using positive sulfur ions generated from SO2 gas...
April 12, 2017: Rapid Communications in Mass Spectrometry: RCM
Vítor S Pinto, Susana C R Marques, Paula Rodrigues, M Teresa Barros, M Lourdes Costa, G John Langley, M Tereza Fernandez, Benedito J C Cabral, M Filomena Duarte, Narciso Couto
RATIONALE: The complexation behavior of transition metals with organic azides by electrospray ionization (ESI) tandem mass spectrometry (MS/MS) is not completely understood. In this study, fragmentation patterns of complex ions having azidoacetic acid coordinated to Ni/Co/Fe were elucidated. The role of transition metals in the mediation of ligand rearrangements in gas phase is experimentally supported. METHODS: The complexation of some transition metals, nickel, cobalt and iron, by azidoacetic acid was studied by means of ESI and MS/MS...
April 12, 2017: Rapid Communications in Mass Spectrometry: RCM
Inigo A Müller, Alvaro Fernandez, Jens Radke, Joep van Dijk, Devon Bowen, Johannes Schwieters, Stefano M Bernasconi
RATIONALE: Clumped isotope analyses (Δ47 ) of carbonates by dual inlet (DI) mass spectrometry require long integration times to reach the necessary high precision due to the low abundance of the rare isotopologue (13) C(18) O(16) O. Traditional DI protocols reach this only with large amounts of sample and/or a large number of replicates as a large portion of the analyte gas is wasted. We tested an improved analytical workflow that significantly reduces the sample sizes and total analysis time per sample while preserving precision and accuracy...
April 12, 2017: Rapid Communications in Mass Spectrometry: RCM
Jingwei Yin, Zhongjun Zhao, Xuefang Zhan, Yixiang Duan
RATIONALE: Microwave-induced plasma (MIP) with different discharge gases of argon or helium provides significant plasma-based ambient desorption/ionization sources, which have potential applicability in direct analysis of complex samples without any sample pre-treatment. In this study, experiments were conducted to better understand microwave-induced plasma desorption/ionization (MIPDI) sources and the corresponding ionization mechanisms. METHODS: Emission spectra of microwave-induced argon (MIP-Ar) and helium (MIP-He) plasmas were obtained from the plasma tail flame of a MIP source...
April 12, 2017: Rapid Communications in Mass Spectrometry: RCM
Arif Ahmed, Dongwon Lim, Cheol Ho Choi, Sunghwan Kim
RATIONALE: The theoretical enthalpy calculated from the overall protonation reaction (electron transfer plus hydrogen transfer) in positive-mode (+) atmospheric-pressure photoionization (APPI) was compared with experimental results for 49 aromatic compounds. A linear relationship was observed between the calculated ΔH and the relative abundance of the protonated peak. The parameter gives reasonable predictions for all the aromatic hydrocarbon compounds used in this study. METHODS: A parameter is devised by combining experimental MS data and high-level theoretical calculations...
April 12, 2017: Rapid Communications in Mass Spectrometry: RCM
Mark Maric, Lauren Harvey, Maren Tomcsak, Angelique Solano, Candice Bridge
RATIONALE: In comparison to other violent crimes, sexual assaults suffer from very low prosecution and conviction rates especially in the absence of DNA evidence. As a result, the forensic community needs to utilize other forms of trace contact evidence, like lubricant evidence, in order to provide a link between the victim and the assailant. METHODS: In this study, 90 personal bottled and condom lubricants from the three main marketing types, silicone-based, water-based and condoms, were characterized by direct analysis in real time-time of flight mass spectrometry (DART-TOFMS)...
April 12, 2017: Rapid Communications in Mass Spectrometry: RCM
Will J Backe
RATIONALE: New legislation in the state of Minnesota prohibits the sale of children's personal-care products (PCPs) that contain more than 500 ng/mg formaldehyde. Previous attempts to quantify formaldehyde in PCPs use nonspecific derivatization procedures that employ harsh reagents and/or nonspecific detection. Derivatization of formaldehyde by acetylacetone occurs under mild conditions and is specific for formaldehyde but it has not been investigated using high-performance liquid-chromatography tandem mass-spectrometry (HPLC-MS/MS)...
April 7, 2017: Rapid Communications in Mass Spectrometry: RCM
Michael J Radke, Nathan S Jacobson, Evan H Copland
RATIONALE: Knudsen effusion mass spectrometry (KEMS) shows improved performance with the "restricted collimation" method of Chatillon and colleagues, which consists of two apertures between the Knudsen cell orifice and the ionizer. These apertures define the shape and position of the molecular beam independently of the sample and effusion orifice and as a result reduces background and improves sampling from the Knudsen cell. Modeling of the molecular beam in restricted collimation allows optimization of the apertures' diameters and spacing...
April 6, 2017: Rapid Communications in Mass Spectrometry: RCM
Feng Zhou, Shu Liu, Junpeng Xing, Zhiqiang Liu, Fengrui Song
In order to analyze benzodiazepine in different matrices, the thermal-assisted gasification (TAG) injector was used to separate the analytes from the matrices by additional heat. Metastable argon molecules from direct analysis in real time (DART) was applied to ionize samples via a series of molecule-ion reactions by introducing methanol and alcohol as proton donor. The research result showed this method is effective and rapid in quantification and semi-quantification analysis of benzodiazepines in inorganic salt solution matrix...
April 6, 2017: Rapid Communications in Mass Spectrometry: RCM
Ioana Nuta, Christian Chatillon
We correct an error made in a recent paper in this journal.([1]) In our original paper, the distance between the vaporizing surface of the sample and the first collimating aperture in Knudsen Cell Mass Spectrometry (KCMS), which is noted as H1 , was not correctly taken into account during calculations when using equation (12) in that paper. It was shown that the results, let us suppose the transmission yield of the studied "restricted collimation device", was dependent on this distance. This erratum shows that the molecular transmission yield does not depend on the distance of the vaporizing surface from the restricted collimation device...
April 5, 2017: Rapid Communications in Mass Spectrometry: RCM
Julian Renpenning, Arndt Schimmelmann, Matthias Gehre
RATIONALE: The conventional high-temperature conversion (HTC) approach towards hydrogen compound-specific isotope analysis (CSIA) of halogen-bearing (F, Cl, Br, I) organics suffers from incomplete H2 yields and associated hydrogen isotope fractionation due to generation of HF, HCl, HBr, and HI byproducts. Moreover, the traditional off-line combustion of highly halogenated compounds results in incomplete recovery of water as an intermediary compound for hydrogen isotope ratio mass-spectrometry (IRMS), and hence also leads to isotope fractionation...
April 3, 2017: Rapid Communications in Mass Spectrometry: RCM
Na Wei, Zhenjia Zheng, Yuhua Wang, Yanduo Tao, Yun Shao, Shuyun Zhu, Jinmao You, Xian-En Zhao
RATIONALE: Endocrine disrupting chemicals (EDCs) in environment samples and food stuffs are an increasing serious public health issue due to their potency to interfere and deregulate several aspects of the endocrine system. Because of their extremely low abundance, it remains a challenging task to develop a sensitive detection method. METHODS: 4'-Carbonyl chloride rosamine (CCR) was used as a derivatization reagent for EDCs for the first time. A new ultrasound-assisted in situ derivatization-dispersive liquid-liquid microextraction (UA-DLLME with in situ derivatization) method for multiple EDCs including five estrogens, two alkylphenols, eight bisphenols, seven parabens and triclosan coupled with ultra high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) has been developed and validated...
March 31, 2017: Rapid Communications in Mass Spectrometry: RCM
O J R Gustafsson, T M Guinan, D Rudd, H Kobus, K Benkendorff, N H Voelcker
RATIONALE: Nanostructure-based mass spectrometry imaging (MSI) is a promising technology for molecular imaging of small molecules, without the complex chemical background typically encountered in matrix-assisted molecular imaging approaches.Here, we have enhanced these surfaces with silver (Ag) to provide a second tier of MSI data from a single sample. METHODS: MSI data was acquired through the application of laser desorption/ionization mass spectrometry to biological samples imprinted onto desorption/ionisation on silicon (DIOS) substrates...
March 31, 2017: Rapid Communications in Mass Spectrometry: RCM
Leonidas Mavroudakis, Emmanouil Mavrakis, Antonis Kouvarakis, Spiros A Pergantis
RATIONALE: Sonic-spray ionization mass spectrometry (SSI-MS) has recently been shown to provide similar mass spectra to those generated by electrospray ionization mass spectrometry for a wide range of compounds, i.e. from small inorganic species to peptides, proteins and numerous other biomolecules. However, limited information about this new ionization technique's sensitivity, limit of detection and quantification accuracy has been reported. Especially, its coupling to liquid chromatography needs further development and assessment, along with the introduction of a broad range of applications...
March 31, 2017: Rapid Communications in Mass Spectrometry: RCM
Tingting Gao, Haiping Xue, Lu Lu, Tong Zhang, Han Han
RATIONALE: Piperine is a major constituent of Piper nigrum L. and is a naturally bio-active alkaloid. Piperine structural changes have been shown to result in different biological effects. The present study aims to investigate piperine metabolites in rat plasma, bile, urine, and feces after oral administration. METHODS: The metabolic pathway of piperine in vivo was carried out using ultra-high-performance liquid chromatography (UHLPC) combined with electrospray ionization quadruple time-of-flight tandem mass spectrometry (Q-TOF-MS)...
March 31, 2017: Rapid Communications in Mass Spectrometry: RCM
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