83,930 results match your criteria ions mass

Assessment of the Cytoprotective Effects of High-Dose Valproic Acid Compared to a Clinically Used Lower Dose.

J Surg Res 2021 May 11;266:125-141. Epub 2021 May 11.

Department of Surgery, University of Michigan Health System, Ann Arbor, Michigan; Department of Surgery, Feinberg School of Medicine/Northwestern University, Chicago, Illinois. Electronic address:

Objective: Valproic acid (VPA) treatment improves survival in animal models of injuries on doses higher than those allowed by Food and Drug Administration (FDA). We investigated the proteomic alterations induced by a single high-dose (140mg/kg) of VPA (VPA140) compared to the FDA-approved dose of 30mg/kg (VPA30) in healthy humans. We also describe the proteomic and transcriptomic changes induced by VPA140 in an injured patient. Read More

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A novel dispersive magnetic solid phase microextraction using ionic liquid-coated amino silanized magnetic graphene oxide nanocomposite for high efficient separation/preconcentration of toxic ions from shellfish samples.

Food Chem 2021 May 6;360:130023. Epub 2021 May 6.

School of Pharmacy, Shenyang Key Laboratory of Functional Drug Carrier Materials, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang 110016, PR China. Electronic address:

A novel dispersive magnetic solid phase microextraction (d-MSPE) method using ionic liquid-coated amino silanized magnetic graphene oxide (MGO@SiO-APTES-IL) as adsorbent has been established for enriching and extracting lead(II), copper(II) and cadmium(II) in shellfish samples. The novel nanocomposite was proved synthesized successfully by various characterization technologies. Parameters that could affect the recoveries of target ions were investigated and optimized focusing on adsorption and desorption using Box-Behnken design of response surface methodology (BBD-RSM). Read More

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Discrimination of CBD-, THC- and CBC-type acid cannabinoids through diagnostic ions by UHPLC-HR-MS/MS in negative ion mode.

J Pharm Biomed Anal 2021 May 5;201:114125. Epub 2021 May 5.

Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania "Luigi Vanvitelli", Via Vivaldi 43, I-81100, Caserta, Italy. Electronic address:

The interest in industrial hemp-based products and by-products to be utilized in food and nutraceutical sector is strictly linked to the demand for improved analytical methods to rapidly discriminate acid phytocannabinoid isomers. Indeed, the differentiation of acid phytocannabinoids, also named pre-cannabinoids, is not properly exploited and valued until now, and it is challenging. Herein, using high-resolution MS/MS, the most common pre-cannabinoids with the resorcinol core linked to the alkyl five carbons chain were deeply investigated in terms of their reactivity to collision-induced dissociation, gaining key data on the integrated energy framework of their dissociation pathway. Read More

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Physical-mathematical Model of Substance Redistribution between the Cell and its Hypertonic Solution Environment of Penetrating Cryoprotectants with Relevance to Membrane Potential.

Cryo Letters 2020 Jul-Aug;41(4):209-215

Institute for Problems of Cryobiology and Cryomedicine, The National Academy of Sciences of Ukraine, Kharkiv, Ukraine.

Background: The redistribution of basic ions between the cell cytoplasm and its surrounding medium due to osmotic action affects transmembrane potential and plasma membrane integrity at all stages of low temperature preservation.

Objective: To develop a physical-mathematical model describing the redistribution of osmotically active solutes between the cell and its hypertonic solutions of penetrating cryoprotectants that enables the calculation of kinetic changes in cell volume, cryoprotectant and ion concentrations, as well as the cell transmembrane potential during cell equilibration with cryoprotectant solutions.

Materials And Methods: The study has modeled the mass transfer process of mouse oocytes upon exposure to 1. Read More

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Probing Polyester Branching by Hybrid Trapped Ion-Mobility Spectrometry-Tandem Mass Spectrometry.

J Am Soc Mass Spectrom 2021 May 14. Epub 2021 May 14.

Division of BioAnalytical Chemistry, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, de Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.

Trapped ion-mobility spectrometry combined with quadrupole time-of-flight mass spectrometry (TIMS-QTOFMS) was evaluated as a tool for resolving linear and branched isomeric polyester oligomers. Solutions of polyester samples were infused directly into the ion source employing electrospray ionization (ESI). TIMS-MS provides both mobility and / data on the formed ions, allowing construction of extracted-ion mobilograms (EIMs). Read More

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[Trend of atmosphreic PM_(2. 5) and their components in two districts of Lanzhou City from 2015 to 2019].

Wei Sheng Yan Jiu 2021 Mar;50(2):274-283

Gansu Provincial Center for Disease Control and Prevention, Lanzhou 730000, China.

Objective: To analyse the variation of the fine particulate matter(PM_(2. 5)) concentration and its chemical composition in two districts of Lanzhou City from 2015 to 2019.

Methods: From January 2015 to December 2019, two sampling points, namely residential district(Chengguan District) and industrial district(Xigu District) were selected in Lanzhou City, to collect PM_(2. Read More

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Selective Cadmium Fluorescence Probe Based on Bis-heterocyclic Molecule and its Imaging in Cells.

J Fluoresc 2021 May 13. Epub 2021 May 13.

Department of Biophysical Chemistry, Kobe Pharmaceutical University, 4-19-1 Motoyamakita Machi, Higashinada-Ku, Kobe, 658-8558, Japan.

Fluorescence probes that selectively image cadmium are useful for detecting and tracking the amount of Cd in cells and tissues. In this study, we designed and synthesized a novel Cd fluorescence probe based on the pyridine-pyrimidine structure, 4-(methylsulfanyl)-6-(pyridin-2-yl)pyrimidin-2-amine (3), as a low-molecular-weight fluorescence probe for Cd. Compound 3 could successfully discriminate between Cd and Zn and exhibited a highly selective turn-on response toward Cd over biologically related metal ions. Read More

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[Analysis of water-soluble nutrients in Lycium barbarum leaves and differences between different producing areas].

Zhongguo Zhong Yao Za Zhi 2021 Apr;46(8):2084-2093

Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, State Administration of Traditional Chinese Medicine Key Laboratory of Chinese Medicinal Resources Recycling Utilization, Nanjing University of Chinese Medicine Nanjing 210023, China.

This study is to clarify the composition and content differences of water-soluble nutrients in Lycium barbarum leaves(LBLs) from different areas. The total polysaccharides, free monosaccharides and oligosaccharides, nucleosides and amino acids in 35 batches of LBLs were analyzed with use of spectrophotometry, HPLC-ELSD and UPLC-MS/MS. The results showed that LBLs contained abundant polysaccharides, fructose, glucose, sucrose and maltose, with an average contents of 39. Read More

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Biochemical markers for pregnancy in the spent culture medium of in vitro produced bovine embryos.

Biol Reprod 2021 May 12. Epub 2021 May 12.

School of Agriculture and Veterinary Medicine, University of Brasilia, Brasília, DF, Brazil.

The present study aimed to identify biomarkers to assess the quality of in vitro produced (IVP) bovine embryos in the culture media. IVP embryos on Day (D) 5 of development were transferred to individual drops, where they were maintained for the last 48 h of culture. Thereafter, the medium was collected and the embryos were transferred to the recipients. Read More

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Nanoparticles Determination by Laser Ablation Inductively Coupled Plasma Mass Spectrometry.

J Nanosci Nanotechnol 2021 Nov;21(11):5436-5442

CAS Key Lab for Biomedical Effects of Nanomaterials and Nanosafety, CAS-HKU Joint Laboratory of Metallomics on Health & Environment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.

Quantitatively studying the biodistribution and transformation of nanomaterials is of great importance for nanotoxicological evaluation. Recently, laser ablation inductively coupled plasma mass spectrometry has been employed to distinguish nanoparticles (NPs) with their dissolved ions in biological samples. The principle of the proposal is based on a hypothesis that the intact NPs sampled by laser ablation will generate discrete sharp pulses of signals in ICP-MS measurement, being totally different from the continuous, relatively lower signals generated by ions. Read More

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November 2021

Sampling Efficiency Improvement to an Electrospray Ionization Mass Spectrometer and Its Implications for Liquid Chromatography Based Inlet Systems in the Nanoliter to Milliliter per Minute Flow Range.

J Am Soc Mass Spectrom 2021 May 12. Epub 2021 May 12.

SCIEX, 71 Four Valley Drive, Concord, Ontario L4K 4 V8, Canada.

This paper describes electrospray sampling efficiency measurements obtained on a triple quadrupole mass spectrometer equipped with a large atmosphere to vacuum sampling aperture and modified ion optics designed to confine the ions traveling in the intense expanding gas beam and prevent scattering losses in the entrance optics of the mass analyzer. Sampling efficiency, defined as the ratio of the number of ions captured in the first vacuum stage of the entrance optics to the number of analyte molecules entering the ion source, is a measure of sensitivity that takes into account both ionization efficiency at atmospheric pressure, the efficiency of transporting the ions from atmosphere to vacuum, and the efficiency of confining them in the subsequent gas expansion before mass analysis. Sampling efficiency measurements were conducted under high-performance liquid chromatography sample introduction conditions using columns and flow rates spanning the nanoflow (300 nL/min), microflow (3-60 μL/min), and milliflow (100-500 μL/min) ranges. Read More

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Nickel-Cobalt Hydroxides with Tunable Thin-Layer Nanosheets for High-Performance Supercapacitor Electrode.

Nanoscale Res Lett 2021 May 12;16(1):83. Epub 2021 May 12.

School of Physics and Electronics, Central South University, Changsha, 410083, China.

Layered double hydroxides as typical supercapacitor electrode materials can exhibit superior energy storage performance if their structures are well regulated. In this work, a simple one-step hydrothermal method is used to prepare diverse nickel-cobalt layered double hydroxides (NiCo-LDHs), in which the different contents of urea are used to regulate the different nanostructures of NiCo-LDHs. The results show that the decrease in urea content can effectively improve the dispersibility, adjust the thickness and optimize the internal pore structures of NiCo-LDHs, thereby enhancing their capacitance performance. Read More

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Proanthocyanidins isolated from the leaves of × block the cell cycle and induce apoptosis by inhibiting tyrosinase activity in melanoma cells.

Food Funct 2021 May;12(9):3978-3991

School of Life Science and Engineering, Henan University of Urban Construction, Pingdingshan, Henan 467044, China. and Forestry College, Henan Agricultural University, Zhengzhou, Henan 450000, China.

Tyrosinase is considered a molecular marker of melanoma, and few natural antitumor drugs targeting tyrosinase have been identified. In this study, proanthocyanidins (PAs) were isolated from the leaves of Photinia × fraseri and their structures were characterized by high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS), and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and the effects of antityrosinase activity were investigated. The results showed that the basic structural units of PAs are composed of catechin and epicatechin and that oligomer is the main component. Read More

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Determination of ultra-trace levels of titanium in human serum using inductively coupled plasma tandem mass spectrometry based on O/H reaction gas.

Anal Chim Acta 2021 Jun 24;1165:338564. Epub 2021 Apr 24.

Hunan Academy of Chinese Medicine, Hunan University of Chinese Medicine, Changsha, 410013, PR China.

This study proposes a new strategy to determine ultra-trace Ti in human serum using inductively coupled plasma tandem mass spectrometry (ICP-MS/MS). The human serum samples were diluted with 1% (v/v) HNO, followed by the determination of ultra-trace Ti using ICP-MS/MS. In the MS/MS mode, a small amount of H was mixed with O (the reaction gas) in a collision reaction cell (CRC) to form an O/H reaction mixture, and then, the conversion of Ti to TiO was determined by the O mass shift method. Read More

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Qualitative screening and quantitative determination of multiclass water-soluble synthetic dyes in foodstuffs by liquid chromatography coupled to quadrupole Orbitrap mass spectrometry.

Food Chem 2021 Apr 24;360:129948. Epub 2021 Apr 24.

Lehn Institute of Functional Materials, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China. Electronic address:

A LC-Q-Orbitrap HRMS analytical method for both qualitative screening and quantitative determination of 90 synthetic dyes including ten groups of isomers in foods has been established. An in-house synthetic dyes database and characteristic ions were also developed. Based on Q-Orbitrap HRMS, mass spectrum and fragmentation patterns of synthetic dyes were studied, which indicated that double charged ions were usually the main precursor ions. Read More

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Antimicrobial activities of Bacillus velezensis strains isolated from stingless bee products against methicillin-resistant Staphylococcus aureus.

PLoS One 2021 11;16(5):e0251514. Epub 2021 May 11.

Enzyme and Microbial Technology Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.

Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) have reached epidemic proportions globally. Therefore, there is an urgent need for a continuous supply of antibiotics to combat the problem. In this study, bacteria initially identified as species belonging to the Bacillus amyloliquefaciens operational group were re-identified based on the housekeeping gene, gyrB. Read More

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Visualizing Lithiation of Graphite Composite Anodes in All-Solid-State Batteries Using Time-of-Flight Secondary Ion Mass Spectrometry.

J Phys Chem Lett 2021 May 11:4623-4627. Epub 2021 May 11.

Applied Materials Technology Center, Technology Division, Panasonic Corporation, 3-1-1 Yagumo-nakamachi, Moriguchi, Osaka 570-8501, Japan.

A fundamental understanding of lithiation dynamics in composite electrodes is essential for the development of all-solid-state batteries with high capacity and rate capability. However, a comprehensive methodology to monitor the time evolution of lithiation in a composite electrode has not been fully established because of the limitations of the characterization techniques currently employed. In this study, we demonstrate the visualization of the transient distribution of Li in composite graphite anodes during cell operation using time-of-flight secondary ion mass spectrometry. Read More

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Determination of phytic acid in wheat products by complete methyl esterification and liquid chromatography-mass spectrometry analysis.

J Sep Sci 2021 May 11. Epub 2021 May 11.

Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, 311121.

Phytic acid, the principal storage form of phosphorus in wheat, plays both beneficial and anti-nutrient functions for human-being, and its analytical method still needs further development. In this work, we have developed a new method for the determination of phytic acid in wheat products based on derivatization with (trimethylsilyl)diazomethane in combination with liquid chromatography-mass spectrometry analysis. Methyl esterification greatly decreased the polarity and the acidity of phytic acid, and thus the corresponding derivative can be easily analyzed by liquid chromatography-mass spectrometry under common conditions. Read More

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Bond dissociation energies of low-valent lanthanide hydroxides: lower limits from ion-molecule reactions and comparisons with fluorides.

Phys Chem Chem Phys 2021 May 11. Epub 2021 May 11.

Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.

Despite that bond dissociation energies (BDEs) are among the most fundamental and relevant chemical properties they remain poorly characterized for most elementary lanthanide hydroxides and halides. Lanthanide ions Ln+ = Eu+, Tm+ and Yb+ are here shown to react with H2O to yield hydroxides LnOH+. Under low-energy conditions such reactions must be exothermic, which implies a lower limit of 499 kJ mol-1 for the Ln+-OH BDEs. Read More

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Ultra-high mechanical property and multi-layer porous structure of amidoximation ethylene-acrylic acid copolymer balls for efficient and selective uranium adsorption from radioactive wastewater.

Chemosphere 2021 Apr 30;280:130722. Epub 2021 Apr 30.

Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin, 150001, China; Institute of Advanced Marine Materials, Harbin Engineering University, 150001, China. Electronic address:

Adsorption uranium [U(VI)] from U-containing radioactive wastewater (URW) is a critical strategy for solving the resource shortage and environmental pollution in pace with the sustainable development of nuclear energy. However, the URW universally exhibits acidity and contains co-existing metal ions with high concentration. Herein, the amidoximation ethylene-acrylic acid copolymer balls (EAA-AO) with aciduric and super-high mechanical property were successfully synthesized through grafting diaminomaleonitrile and further treatment of amidoximation. Read More

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growth of ZIF-8 on gold nanoparticles/magnetic carbon nanotubes for the electrochemical detection of bisphenol A.

Anal Methods 2021 May 10. Epub 2021 May 10.

College of Chemistry and Chemical Engineering, Key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety, Central South University, Changsha 410083, China.

We herein report a facile and scalable strategy for the fabrication of a metal-organic framework (MOF) based composite by in situ growing ZIF-8 on gold nanoparticle (AuNP) loaded magnetic carbon nanotubes (mCNTs). AuNPs were firstly loaded on PEI (polyethylenimine) modified mCNTs by electrostatic forces, and then AuNPs/mCNTs were encapsulated into the ZIF-8 frame through in situ self-assembling of zinc ions and 2-methylimidazole. The morphology, spectroscopy and structural properties of the AuNP/mCNT@ZIF-8 nanocomposites were systematically characterized. Read More

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The physiology of fish in acidic waters rich in dissolved organic carbon, with specific reference to the Amazon basin: Ionoregulation, acid-base regulation, ammonia excretion, and metal toxicity.

J Exp Zool A Ecol Integr Physiol 2021 May 10. Epub 2021 May 10.

Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada.

Although blackwaters, named for their rich content of dissolved organic carbon (DOC), are often very poor in ions and very acidic, they support great fish biodiversity. Indeed, about 8% of all freshwater fish species live in the blackwaters of the Rio Negro watershed in the Amazon basin. We review how native fish survive these harsh conditions that would kill most freshwater fish, with a particular focus on the role of DOC, a water quality parameter that has been relatively understudied. Read More

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Enabling LIFDI-MS measurements of highly air sensitive organometallic compounds: a combined MS/glovebox technique.

Dalton Trans 2021 May 10. Epub 2021 May 10.

Department of Chemistry, Technical University of Munich, Lichtenbergstraße 4, D-85748 Garching, Germany. and Catalysis Research Center, Technical University of Munich, Ernst-Otto-Fischer-Straße 1, D-85748 Garching, Germany.

A new setup combining a ThermoFisher Exactive Plus Orbitrap Mass Spectrometer with a liquid injection field desorption ionization (LIFDI) source directly connected to an inert atmosphere glovebox is presented. The described setup allows for the analysis of very air- and moisture sensitive samples. Furthermore, the soft nature of LIFDI ionization gives access to the molecular ions of fragile molecules. Read More

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Electrostatic Self-Assembly Synthesis of Three-Dimensional Mesoporous Lepidocrocite-Type Layered Sodium Titanate as a Superior Adsorbent for Selective Removal of Cationic Dyes via an Ion-Exchange Mechanism.

Langmuir 2021 May 9. Epub 2021 May 9.

Department of Advanced Materials Science, Faculty of Engineering and Design, Kagawa University, 2217-20 Hayashi-cho, Takamatsu 761-0396, Japan.

Three-dimensional mesoporous lepidocrocite-type layered sodium titanate (LST) was constructed at room temperature by the electrostatic interaction between TiO nanosheets and Na ions. The results of a systematic X-ray diffraction investigation manifested the transition from the TiO nanosheets phase to the titanate/titania phase, which determined a phase diagram as a function of the temperature and NaCl concentration. In addition, scanning electron microscopy, inductively coupled plasma-mass spectrometry, thermogravimetric and differential thermal, N adsorption-desorption, Raman spectroscopy, Fourier transform infrared spectroscopy, as well as ζ-potential analyses were utilized for adequate characterization of the LST physical and chemical properties. Read More

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Green Synthesized Silver Nanoparticles: Antibacterial and Anticancer Activities, Biocompatibility, and Analyses of Surface-Attached Proteins.

Front Microbiol 2021 22;12:632505. Epub 2021 Apr 22.

Department of Microbiology, Nicolaus Copernicus University, Toruń, Poland.

The increasing number of multi-drug-resistant bacteria and cancer cases, that are a real threat to humankind, forces research world to develop new weapons to deal with it. Biogenic silver nanoparticles (AgNPs) are considered as a solution to this problem. Biosynthesis of AgNPs is regarded as a green, eco-friendly, low-priced process that provides small and biocompatible nanostructures with antimicrobial and anticancer activities and potential application in medicine. Read More

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Transcriptional and metabolite analysis reveal a shift in fruit quality in response to calcium chloride treatment on "Kyoho" grapevine.

J Food Sci Technol 2021 Jun 19;58(6):2246-2257. Epub 2020 Aug 19.

Key Laboratory of Genetics and Fruit Development, College of Horticulture, Nanjing Agricultural University, Nanjing, 210018 PR China.

'Kyoho' grapevine () treated by calcium ions solution has been proved as an effective treatment to extend grape quality during storage to reduce disease, but its molecular mechanism was not clear yet. In the current work, grape berries were treated with different concentration of Calcium chloride (CaCl) solution, and their effects on antioxidant enzyme activity and transcriptome and metabolome in fruit were investigated. CaCl treatments reduced weight loss and inhibited the decrement of flesh firmness. Read More

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Label-free microRNA detection through analyzing the length distribution pattern of the residual fragments of probe DNA produced during exonuclease III assisted signal amplification by mass spectrometry.

Talanta 2021 Aug 16;231:122414. Epub 2021 Apr 16.

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

Biosensors based on various spectroscopic techniques discriminate the target microRNA (miRNA) from non-target ones with single nucleotide polymorphisms (SNPs) according to the differences in signal intensities which can be caused by other factors besides SNPs. As a result, they are liable to produce false positive results. Herein, we report an attempt to develop a false-positive resistance, sensitive and reliable mass spectrometric platform for miRNA detection. Read More

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Low-molecular-mass labile metal pools in Escherichia coli: advances using chromatography and mass spectrometry.

J Biol Inorg Chem 2021 May 8. Epub 2021 May 8.

Department of Chemistry, Texas A&M University, College Station, TX, 77843-3255, USA.

Labile low-molecular-mass (LMM) transition metal complexes play essential roles in metal ion trafficking, regulation, and signalling in biological systems, yet their chemical identities remain largely unknown due to their rapid ligand-exchange rates and weak M-L bonds. Here, an Escherichia coli cytosol isolation procedure was developed that was devoid of detergents, strongly coordinating buffers, and EDTA. The interaction of the metal ions from these complexes with a SEC column was minimized by pre-loading the column with ZnSO and then monitoring Zn and other metals by inductively coupled plasma mass spectrometry (ICP-MS) when investigating cytosolic ultrafiltration flow-through-solutions (FTSs). Read More

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Comparison of analyte identification criteria and other aspects in triple quadrupole tandem mass spectrometry: Case study using UHPLC-MS/MS for regulatory analysis of veterinary drug residues in liquid and powdered eggs.

Steven J Lehotay

Anal Bioanal Chem 2021 May 7. Epub 2021 May 7.

U.S. Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, 600 East Mermaid Lane, Wyndmoor, PA, 19038, USA.

Ultrahigh-performance liquid chromatography (UHPLC) coupled with triple quadrupole tandem mass spectrometry (MS/MS) is one of the most powerful tools for the multiclass, multiresidue analysis of veterinary drugs, pesticides, mycotoxins, and other chemical contaminants in foods and other sample types. Until approximately 2010, commercial MS/MS instruments using multiple reaction monitoring (MRM) were generally limited to minimum dwell (and inter-dwell) times of 10 ms per ion transition. To achieve the needed accuracy and detection limits for hundreds of targeted analytes, older UHPLC-MS/MS methods typically acquired only two ion transitions per analyte (yielding only one ion ratio for qualitative identification purposes), which is still the norm despite technological advancements. Read More

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High-Yielding Flow Synthesis of a Macrocyclic Molecular Hinge.

J Am Chem Soc 2021 May 7. Epub 2021 May 7.

Department of Chemistry and Materials Innovation Factory, University of Liverpool, Crown Street, Liverpool L69 7ZD, U.K.

Many molecular machines are built from modular components with well-defined motile capabilities, such as axles and wheels. Hinges are particularly useful, as they provide the minimum flexibility needed for a simple and pronounced conformational change. Compounds with multiple stable conformers are common, but molecular hinges almost exclusively operate via dihedral rotations rather than truly hinge-like clamping mechanisms. Read More

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