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https://www.readbyqxmd.com/read/29145156/the-potential-of-ion-mobility-mass-spectrometry-for-high-throughput-and-high-resolution-lipidomics
#1
REVIEW
Christine Hinz, Sonia Liggi, Julian L Griffin
Lipids are a large and highly diverse family of biomolecules, which play essential structural, storage and signalling roles in cells and tissues. Although traditional mass spectrometry (MS) approaches used in lipidomics are highly sensitive and selective, lipid analysis remains challenging due to the chemical diversity of lipid structures, multiple isobaric species and incomplete separation using many forms of chromatography. Ion mobility (IM) separates ions in the gas phase based on their physicochemical properties...
November 13, 2017: Current Opinion in Chemical Biology
https://www.readbyqxmd.com/read/29145024/direct-analysis-of-ethylene-glycol-in-human-serum-on-the-basis-of-analyte-adduct-formation-and-liquid-chromatography-tandem-mass-spectrometry
#2
Marek Dziadosz
The aim of this work was to develop a fast, cost-effective and time-saving liquid chromatography-tandem mass spectrometry (LC-MS/MS) analytical method for the analysis of ethylene glycol (EG) in human serum. For these purposes, the formation/fragmentation of an EG adduct ion with sodium and sodium acetate was applied in the positive electrospray mode for signal detection. Adduct identification was performed with appropriate infusion experiments based on analyte solutions prepared in different concentrations...
November 12, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29144740/identification-synthesis-and-safety-assessment-of-thidiazuron-1-phenyl-3-1-2-3-thidiazol-5-yl-urea-and-its-metabolites-in-kiwifruits
#3
Zhiwei Zhang, Haihua Yang, Zhenhong Gao, Yahong Yuan, Jing Dong, Yuan Wang, Tianli Yue
Quality of kiwifruit became worse due to the abuse of plant growth regulators (PGRs). The safety of the fruits treated with PGRs are also worried by consumers. Therefore, the present study analysed the structure of thidiazuron (TDZ, (1-phenyl-3-(1,2,3-thidiazol-5-yl)urea)) (1) and its metabolites of bio-transformation in kiwifruits by using liquid chromatography hybrid ion trap time-of-flight mass spectrometry (LC-IT-TOF-MS). Standard compounds were also synthesized and used for structural identification of those metabolites...
November 16, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/29144587/characterization-of-complex-heterogeneous-lipid-a-samples-using-hplc-ms-ms-technique-iii-positive-ion-mode-tandem-mass-spectrometry-to-reveal-phosphorylation-and-acylation-patterns-of-lipid-a
#4
Viktor Sándor, Anikó Kilár, Ferenc Kilár, Béla Kocsis, Ágnes Dörnyei
In this study, we report the detailed analysis of the fragmentation patterns of positively charged lipid A species based on their tandem mass spectra obtained under low-energy collision-induced dissociation conditions of an electrospray quadrupole time-of-flight mass spectrometers. The tandem mass spectrometry experiments were performed after the separation of the compounds with a reversed-phase high performance liquid chromatography method. We found that both, phosphorylated and nonphosphorylated lipid A molecules can be readily ionized in the positive-ion mode by adduct formation with triethylamine added to the eluent...
November 16, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/29142408/correlation-between-polyphenol-oxidase-ppo-activity-and-total-phenolic-contents-in-crocus-sativus-l-corms-during-dormancy-and-sprouting-stages
#5
Nardana Esmaeili, Hassan Ebrahimzadeh, Khosrou Abdi
Purification and characterization of polyphenol oxidase (PPO) enzyme and determination of total phenolic contents during dormancy and sprouting stages in Crocus sativus corms were performed. PPO enzyme was purified by ammonium sulfate precipitation and ion-exchange chromatography using DEAE-Sephadex A25 and two isoenzymes were obtained on the SDS-PAGE, which corresponded to molecular weights of 70 and 54 kDa. The Km values of the enzyme were 4.87 and 2.12 mM for l-DOPA in dormancy and waking stages, respectively...
October 2017: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/29142394/antioxidant-phytochemicals-of-opuntia-ficus-indica-l-mill-cladodes-with-potential-anti-spasmodic-activity
#6
Francesco Lanuzza, Francesco Occhiuto, Maria Teresa Monforte, Maria Marcella Tripodo, Valeria D'Angelo, Enza Maria Galati
Background: Opuntia ficus-indica (OFI) (L.) Mill. (Cactaceae), a plant widespread in dry regions of the world, shows interesting biological activities (cicatrizant, antiulcer, anti-inflammatory, and hypolipidemic) and is widely used in traditional medicine. Objectives: Phytochemical analysis and antispasmodic effect of wild OFI cladodes were carried out. Material and Methods: Polyphenols and Vitamin E occurrence, in antioxidant pool of OFI cladodes, were quantified by high-performance liquid chromatography...
October 2017: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/29141721/coupling-ion-chromatography-to-q-orbitrap-for-the-fast-and-robust-analysis-of-anionic-pesticides-in-fruits-and-vegetables
#7
Łukasz Rajski, Francisco José Díaz Galiano, Víctor Cutillas, Amadeo R Fernández-Alba
Ion chromatography coupled to a quadrupole Orbitrap mass analyzer was used to develop a multiresidue method for the determination of highly polar pesticides and their metabolites (chlorate, perchlorate, fosetyl-aluminum, glyphosate, aminomethylphosphonic acid (AMPA), phosphonic acid, N-acetyl AMPA, and N-acetyl glyphosate) in fruits and vegetables. After extraction with methanol, samples were diluted 5× with water. No derivatization was applied. Pesticides were separated in an anion-exchange column. Water was used as the ion chromatography mobile phase...
November 15, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/29141711/application-of-gas-chromatography-coupled-to-quadrupole-orbitrap-mass-spectrometry-for-pesticide-residue-analysis-in-cereals-and-feed-ingredients
#8
Marc Tienstra, Hans G J Mol
A method for residue analysis of pesticides and polychlorinated biphenyls in cereals and feed ingredients based on QuEChERS extraction, programmed temperature vaporizer large-volume injection, and GC with electron ionization (EI) quadrupole Orbitrap full-scan high-resolution MS (60 000 full width at half-maximum at m/z 200) has been developed. In addition to full-scan acquisition, simultaneous full-scan and selected-ion monitoring acquisition was used to improve detectability in incidental cases in which analytes coeluted with intense signals from coextractants...
November 16, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/29141708/sensitive-detection-of-neonicotinoid-insecticides-and-other-selected-pesticides-in-pollen-and-nectar-using-nanoflow-liquid-chromatography-orbitrap-tandem-mass-spectrometry
#9
David Moreno-González, Jaime Alcántara-Durán, Bienvenida Gilbert-López, Miriam Beneito-Cambra, Víctor M Cutillas, Łukasz Rajski, Antonio Molina-Díaz, Juan F García-Reyes
In this work, a new method based on nanoflow LC with high-resolution MS was developed for the determination ofeight pesticides in pollen and nectar samples, including neonicotinoid insecticides and other selected pesticides commonly found in bees and beeswax. Detection was undertaken with a hybrid quadrupole-Orbitrap mass spectrometer (Q Exactive™) equipped with a commercial nanospray ion source. The extraction of pesticides from pollen samples was performed by a modified micro-QuEChERS method scaled down to Eppendorf tubes, whereas nectar samples were simply diluted with a water–methanol (95 + 5, v/v) solution...
November 15, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/29140480/the-intrinsically-disordered-n-terminal-arm-of-the-brome-mosaic-virus-coat-protein-specifically-recognizes-the-rna-motif-that-directs-the-initiation-of-viral-rna-replication
#10
Alexander Jacobs, Haley Hoover, Edward Smith, David E Clemmer, Chul-Hyun Kim, C Cheng Kao
In the brome mosaic virus (BMV) virion, the coat protein (CP) selectively contacts the RNA motifs that regulate translation and RNA replication (Hoover et al., 2016. J. Virol. 90, 7748). We hypothesize that the unstructured N-terminal arm (NTA) of the BMV CP can specifically recognize RNA motifs. Using ion mobility spectrometry-mass spectrometry, we demonstrate that peptides containing the NTA of the CP were found to preferentially bind to an RNA hairpin motif that directs the initiation of BMV RNA synthesis...
November 11, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/29140413/comparison-of-chemical-constituents-in-scrophulariae-radix-processed-by-different-methods-based-on-uflc-ms-combined-with-multivariate-statistical-analysis
#11
Shengnan Wang, Yujiao Hua, Lisi Zou, Xunhong Liu, Ying Yan, Hui Zhao, Yiyuan Luo, Juanxiu Liu
Scrophulariae Radix is one of the most popular traditional Chinese medicines (TCMs). Primary processing of Scrophulariae Radix is an important link which closely related to the quality of products in this TCM. The aim of this study is to explore the influence of different processing methods on chemical constituents in Scrophulariae Radix. The difference of chemical constituents in Scrophulariae Radix processed by different methods was analyzed by using ultra fast liquid chromatography-triple quadrupole-time of flight mass spectrometry coupled with principal component analysis and orthogonal partial least squares discriminant analysis...
November 13, 2017: Journal of Chromatographic Science
https://www.readbyqxmd.com/read/29140143/sweat-sodium-potassium-and-chloride-concentrations-analyzed-same-day-as-collection-versus-after-seven-days-storage-in-a-range-of-temperatures
#12
Lindsay B Baker, Kelly A Barnes, Bridget C Sopeña, Ryan P Nuccio, Adam J Reimel, Corey T Ungaro
The purpose of this study was to determine the effect of storage temperature on sodium ([Na(+)]), potassium ([K(+)]), and chloride ([Cl(-)]) concentrations of sweat samples analyzed seven days after collection. Using the absorbent patch technique, 845 sweat samples were collected from 39 subjects (32±7 y, 72.9±10.5 kg) during exercise. On the same day as collection (PRE-STORAGE), 609 samples were analyzed for [Na(+)], [Cl(-)], and [K(+)] via ion chromatography (IC) and 236 samples were analyzed for [Na(+)] using a compact ion-selective electrode (ISE)...
November 15, 2017: International Journal of Sport Nutrition and Exercise Metabolism
https://www.readbyqxmd.com/read/29136899/characterization-of-mercury-binding-proteins-in-human-neuroblastoma-sk-n-sh-cells-with-immobilized-metal-affinity-chromatography
#13
Yiling Li, Bin He, Ligang Hu, Xiu Huang, Zhaojun Yun, Runzeng Liu, Qunfang Zhou, Guibin Jiang
Metal-binding proteins play important roles in biological functions of metals. However, only very limited mercury-binding proteins with high abundance were characterized in cells or organisms. Characterization of mercury-binding proteins in proteome-wide is important for elucidating mechanisms of mercury toxicity comprehensively. In this study, a method based on immobilized mercury ion affinity chromatography was developed for identification of putative mercury-binding proteins. The method was then successfully applied to profile mercury-binding proteins in human neuroblastoma SK-N-SH cells...
February 1, 2018: Talanta
https://www.readbyqxmd.com/read/29136864/suspect-screening-of-halogenated-carboxylic-acids-in-drinking-water-using-ion-exchange-chromatography-high-resolution-orbitrap-mass-spectrometry-ic-hrms
#14
Matteo D Gallidabino, Laurence Hamdan, Bronagh Murphy, Leon P Barron
Retrospective in silico screening of analytical data for the identification of new or emerging disinfection by-products in drinking waters could be useful to assess quality and potential hazards, as well as help implement mitigation procedures more rapidly. Herein, the first study coupling ion exchange chromatography (IC) with high resolution mass spectrometry (HRMS) for the determination of halogenated carboxylic acid disinfectant by-products is reported. Separation was achieved using a Metrohm A Supp 5 column and a Na2CO3/NaHCO3 gradient eluent from 1/0...
February 1, 2018: Talanta
https://www.readbyqxmd.com/read/29136836/detection-of-new-emerging-type-a-trichothecenes-by-untargeted-mass-spectrometry
#15
Jesús M González-Jartín, Amparo Alfonso, María J Sainz, Mercedes R Vieytes, Luis M Botana
Mycotoxins occur naturally as agricultural contaminants all over the world. The toxic effects of some of their metabolites are known and their presence regulated in food and feed. This paper describes two methods for the detection of toxins of type-A trichothecenes group, and their modified forms, using mass spectrometry. Ultra-performance liquid chromatography coupled to mass spectrometry-ion trap-time of flight (UPLC-MS-IT-TOF) was employed to characterize the fragmentation pathways of 10 type-A trichothecenes, and characteristic ions were tentatively identified in scan mode through their accurate masses...
February 1, 2018: Talanta
https://www.readbyqxmd.com/read/29136813/isolation-of-236-u-and-239-240-pu-from-seawater-samples-and-its-determination-by-accelerator-mass-spectrometry
#16
Mercedes López-Lora, Elena Chamizo, María Villa-Alfageme, Santiago Hurtado-Bermúdez, Núria Casacuberta, Manuel García-León
In this work we present and evaluate a radiochemical procedure optimised for the analysis of (236)U and (239,240)Pu in seawater samples by Accelerator Mass Spectrometry (AMS). The method is based on Fe(OH)3 co-precipitation of actinides and uses TEVA® and UTEVA® extraction chromatography resins in a simplified way for the final U and Pu purification. In order to improve the performance of the method, the radiochemical yields are analysed in 1 to 10L seawater volumes using alpha spectrometry (AS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS)...
February 1, 2018: Talanta
https://www.readbyqxmd.com/read/29136812/silica-based-click-dibenzo-18-crown-6-ether-high-performance-liquid-chromatography-stationary-phase-and-its-application-in-separation-of-fullerenes
#17
Yanzhe Li, Zhe Sheng, Chuanlei Zhu, Wei Yin, Changhu Chu
Crown ether is a type of typical macrocyclic polyether compounds, which can produce strong interactions with cationic species, such as metal ions and protonated amines due to its cavity structure and the strong electronegative effect of heteroatoms on the crown ether ring. In this paper, a type of silica based crown ether stationary phase was prepared by covalently bonding dibenzo-18-crown 6-ether (DBCE) on silica gel via copper (I) catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC). The tetraazido DBCE was rapidly prepared by bromomethylation and subsequent azido substitution of DBCE...
February 1, 2018: Talanta
https://www.readbyqxmd.com/read/29135039/a-novel-fast-method-for-aqueous-derivatization-of-thc-oh-thc-and-thc-cooh-in-human-whole-blood-and-urine-samples-for-routine-forensic-analyses
#18
Fabio Stefanelli, Federica Giorgia Pesci, Mario Giusiani, Silvio Chericoni
A novel aqueous in situ derivatization procedure with propyl chloroformate (PCF) for the simultaneous, quantitative analysis of Δ(9) -tetrahydrocannabinol (THC), 11-hydroxy-Δ(9) -tetrahydrocannabinol (OH-THC) and 11-nor-Δ(9) -tetrahydrocannabinol-carboxylic acid (THC-COOH) in human blood and urine is proposed. Unlike current methods based on the silylating agent (BSTFA) added in an anhydrous environment, this new proposed method allows to add the derivatizing agent (propyl chloroformate, PCF) directly to the deproteinized blood and recover the derivatives by liquid-liquid extraction...
November 14, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/29134782/determination-of-the-clean-up-efficiency-of-the-solid-phase-extraction-of-rosemary-extracts-application-of-full-factorial-design-in-hyphenation-with-gaussian-peak-fit-function
#19
Florian Meischl, Christian G Kirchler, Michael A Jäger, Christian W Huck, Matthias Rainer
We present a novel method for the quantitative determination of the clean-up efficiency to provide a calculated parameter for peak purity through iterative fitting in conjunction with design of experiments. Rosemary extracts were used and analyzed before and after solid-phase extraction using a self-fabricated mixed-mode sorbent based on poly(N-vinylimidazole/ethylene glycol dimethacrylate). Optimization was performed by variation of washing steps using a full three-level factorial design and response surface methodology...
November 14, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/29134743/rapid-determination-of-ginkgolic-acids-in-ginkgo-biloba-kernels-and-leaves-by-direct-analysis-in-real-time-mass-spectrometry
#20
Zhongping Huang, Yueting Xu, Yilei Huang, Charles Liu, Kezhi Jiang, Lili Wang
A novel method on basis of direct analysis in real time integrated with mass spectrometry was established and applied into rapid determination of ginkgolic acids in Ginkgo biloba kernels and leaves. Instrument parameter settings were optimized to obtain the sensitive and accurate determination of ginkgolic acids. At the sample introduction speed of 0.2 mm/s, high intensity of [M-H](-) ions for ginkgolic acids were observed in the negative ion mode by utilization of high purity helium gas at 450°C. 2 μL methanol extract of Ginkgo biloba kernels or leaves dropped on the surface of Quick-Strip module was analyzed after solvent evaporated to dryness...
November 14, 2017: Journal of Separation Science
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