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Secondary ion mass spectrometry

Giulia Zanni, Wojciech Michno, Elena Di Martino, Anna Tjärnlund-Wolf, Jean Pettersson, Charlotte Elizabeth Mason, Gustaf Hellspong, Klas Blomgren, Jörg Hanrieder
Lithium (Li) is a potent mood stabilizer and displays neuroprotective and neurogenic properties. Despite extensive investigations, the mechanisms of action have not been fully elucidated, especially in the juvenile, developing brain. Here we characterized lithium distribution in the juvenile mouse brain during 28 days of continuous treatment that result in clinically relevant serum concentrations. By using Time-of-Flight Secondary Ion Mass Spectrometry- (ToF-SIMS) based imaging we were able to delineate temporospatial lithium profile throughout the brain and concurrent distribution of endogenous lipids with high chemical specificity and spatial resolution...
January 18, 2017: Scientific Reports
Michael Landreh, Erik G Marklund, Povilas Uzdavinys, Matteo T Degiacomi, Mathieu Coincon, Joseph Gault, Kallol Gupta, Idlir Liko, Justin L P Benesch, David Drew, Carol V Robinson
Na(+)/H(+) antiporters are found in all kingdoms of life and exhibit catalysis rates that are among the fastest of all known secondary-active transporters. Here we combine ion mobility mass spectrometry and molecular dynamics simulations to study the conformational stability and lipid-binding properties of the Na(+)/H(+) exchanger NapA from Thermus thermophilus and compare this to the prototypical antiporter NhaA from Escherichia coli and the human homologue NHA2. We find that NapA and NHA2, but not NhaA, form stable dimers and do not selectively retain membrane lipids...
January 10, 2017: Nature Communications
Byung-Man Kim, Hyun-Gyu Han, Jeong Soo Kim, HyeonOh Shin, Tae-Hyuk Kwon
Dye distribution in a mesoporous TiO2 film is a key factor in the performance of dye-sensitized solar cells, but there has been little research on it. Here we report even dye distribution within the porous TiO2 film achieved by a physical driving force of gas flow. Gas-assisted dye arrangement, gas bubbling soaking (GBS), significantly accelerates the dye infiltration compared to conventional overnight soaking (OS). As a demonstration, we investigated the time-dependent dye infiltration using plasmon sensors...
January 12, 2017: ACS Applied Materials & Interfaces
Ryutaro Souda
Methanol is known as a strong inhibitor of hydrate formation, but clathrate hydrates of ethanol and 1-propanol can be formed in the presence of help gases. To elucidate the hydrophilic and hydrophobic effects of alcohols, their interactions with simple solute species are investigated in glassy, liquid, and crystalline water using temperature-programmed desorption and time-of-flight secondary ion mass spectrometry. Nonpolar solute species embedded underneath amorphous solid water films are released during crystallization, but they tend to withstand water crystallization under the coexistence of methanol additives...
January 18, 2017: Physical Chemistry Chemical Physics: PCCP
Dan Aoki, Kazuhiko Fukushima
Time-of-flight secondary ion mass spectrometry (TOF-SIMS) is a recently developing analytical tool and a type of imaging mass spectrometry. TOF-SIMS provides mass spectral information with a lateral resolution on the order of submicrons, with widespread applicability. Sometimes, it is described as a surface analysis method without the requirement for sample pretreatment; however, several points need to be taken into account for the complete utilization of the capabilities of TOF-SIMS. In this chapter, we introduce methods for TOF-SIMS sample treatments, as well as basic knowledge of wood samples TOF-SIMS spectral and image data analysis...
2017: Methods in Molecular Biology
Yu-Hsien Chiang, Ming-Hsien Li, Hsin-Min Cheng, Po-Shen Shen, Peter Chen
Novel organic-inorganic hybrid perovskite compounds composed of mixed A-site cation (Formamidinium and Cesium) and pseudohalides (SCN and I) ions are successfully synthesized. These new classes of hybrid perovskites photovoltaics exhibited remarkable power conversion efficiency of more than 16% with excellent stability against moisture in ambient environment and under low-light storage condition. The existence of SCN(-) ion inclusion is confirmed by secondary ion mass spectrometry and Fourier transform infrared spectroscopy...
January 12, 2017: ACS Applied Materials & Interfaces
Minji Kang, Hansu Hwang, Won-Tae Park, Dongyoon Khim, Jun-Seok Yeo, Yunseul Kim, Yeon-Ju Kim, Yong-Young Noh, Dong-Yu Kim
We report on the fabrication of an organic thin-film semiconductor formed using a blend solution of soluble ambipolar small molecules and an insulating polymer binder that exhibits vertical phase separation and uniform film formation. The semiconductor thin films are produced in a single step from a mixture containing a small molecular semiconductor, namely, quinoidal biselenophene (QBS), and a binder polymer, namely, poly(2-vinylnaphthalene) (PVN). Organic field-effect transistors (OFETs) based on QBS/PVN blend semiconductor are then assembled using top-gate/bottom-contact device configuration, which achieve almost four times higher mobility than the neat QBS semiconductor...
January 13, 2017: ACS Applied Materials & Interfaces
Jun-Gang Wang, Xin Hua, Meng Li, Yi-Tao Long
Polydopamine functionalized plasmonic nanocomposites with well distributed catalytically active small gold nanoislands around large gold core were fabricated without using any chemical reductant or surfactant. The optical properties, surface molecular structures and ensemble catalytic activity of the gold nanocomposites were investigated by time-of-flight secondary ion mass spectrometry and UV-Vis spectroscopy, respectively. Moreover, the considerable catalytic activity of the nanocomposites toward 4-nitrophenol reduction was real time monitored by dark-field spectroscopy techniques at single-nanoparticle level avoiding averaging effects in bulk systems...
December 27, 2016: ACS Applied Materials & Interfaces
Sandra L Blair, Amanda C MacMillan, Greg T Drozd, Allen H Goldstein, Rosalie K Chu, Ljiljana Paša-Tolić, Jared B Shaw, Nikola Tolić, Peng Lin, Julia Laskin, Alexander Laskin, Sergey A Nizkorodov
Secondary organic aerosol (SOA), formed in the photooxidation of diesel fuel, biodiesel fuel, and 20% biodiesel fuel/80% diesel fuel mixture, are prepared under high-NOx conditions in the presence and absence of sulfur dioxide (SO2), ammonia (NH3), and relative humidity (RH). The composition of condensed-phase organic compounds in SOA is measured using several complementary techniques including aerosol mass spectrometry (AMS), high-resolution nanospray desorption electrospray ionization mass spectrometry (nano-DESI/HRMS), and ultrahigh resolution and mass accuracy 21T Fourier transform ion cyclotron resonance mass spectrometry (21T FT-ICR MS)...
January 3, 2017: Environmental Science & Technology
Agnieszka Priebe, Pierre Bleuet, Gael Goret, Jerome Laurencin, Dario Montinaro, Jean-Paul Barnes
In this paper the potential of time-of-flight secondary ion mass spectroscopy combined with focused ion beam technology to characterize the composition of a solid oxide fuel cell (SOFC) in three-dimension is demonstrated. The very high sensitivity of this method allows even very small amounts of elements/compounds to be detected and localized. Therefore, interlayer diffusion of elements between porous electrodes and presence of pollutants can be analyzed with a spatial resolution of the order of 100 nm. However, proper element recognition and mass interference still remain important issues...
December 2016: Microscopy and Microanalysis
Jelena Lovrić, Johan Dunevall, Anna Larsson, Lin Ren, Shalini Andersson, Anders Meibom, Per Malmberg, Michael E Kurczy, Andrew G Ewing
We report an approach to spatially resolve the content across nanometer neuroendocrine vesicles in nerve-like cells by correlating super high-resolution mass spectrometry imaging, NanoSIMS, with transmission electron microscopy (TEM). Furthermore, intracellular electrochemical cytometry at nanotip electrodes is used to count the number of molecules in individual vesicles to compare to imaged amounts in vesicles. Correlation between the NanoSIMS and TEM provides nanometer resolution of the inner structure of these organelles...
December 27, 2016: ACS Nano
Jae-Il Jung, Daekyeom Kim, Hyojin Kim, Yong Nam Jo, Jung Sik Park, Youngsik Kim
The successful analysis on the microstructure of Hong-type Na superionic conducting (NASICON) ceramics revealed that it consists of several heterogeneous phases: NASICON grains with rectangular shapes, monoclinic round ZrO2 particles, grain boundaries, a SiO2-rich vitrified phase, Na-rich amorphous particles, and pores. A dramatic microstructural evolution of NASICON ceramics was demonstrated via an in situ analysis, which showed that NASICON grains sequentially lost their original morphology and were transformed into comminuted particles (as indicated by the immersion of bulk NASICON samples into seawater at a temperature of 80 °C)...
December 27, 2016: ACS Applied Materials & Interfaces
Jongcheol Seo, Waldemar Hoffmann, Stephan Warnke, Xing Huang, Sandy Gewinner, Wieland Schöllkopf, Michael T Bowers, Gert von Helden, Kevin Pagel
Amyloidogenic peptides and proteins play a crucial role in a variety of neurodegenerative disorders such as Alzheimer's and Parkinson's disease. These proteins undergo a spontaneous transition from a soluble, often partially folded form, into insoluble amyloid fibrils that are rich in β-sheets. Increasing evidence suggests that highly dynamic, polydisperse folding intermediates, which occur during fibril formation, are the toxic species in the amyloid-related diseases. Traditional condensed-phase methods are of limited use for characterizing these states because they typically only provide ensemble averages rather than information about individual oligomers...
January 2017: Nature Chemistry
Mehrnoosh Azodi, Yasir Sultan, Subhasis Ghoshal
Ag nanoparticles (nAg) are used in various consumer products and a significant fraction is eventually discharged with municipal wastewater (WW). In this study we assessed the release of Ag from polyvinylpyrrolidone (PVP)- and citrate-coated 80 nm nAg in aerobic WW effluent and mixed liquor and the related changes in nAg size, using single particle ICP-MS (spICP-MS). The concentration of dissolved (nonparticulate) Ag in WW effluent was 0.89 ± 0.05 ppb at 168 h and was 71% lower than in deionized (DI) water, in batch reactors spiked with 5 × 10(6) PVP-nAg particles/mL (10 μg/L), an environmentally relevant concentration...
December 20, 2016: Environmental Science & Technology
Ivan J Hall Barrientos, Eleonora Paladino, Sarah Brozio, Melissa K Passarelli, Susan Moug, Richard A Black, Clive G Wilson, Dimitrios A Lamprou
The chemical distribution and mechanical effects of drug compounds in loaded electrospun scaffolds, a potential material for hernia repair mesh, were characterised and the efficacy of the material was evaluated. Polycaprolactone electrospun fibres were loaded with either the antibacterial agent, irgasan, or the broad-spectrum antibiotic, levofloxacin. The samples were subsequently characterised by rheological studies, scanning electron microscopy (SEM), atomic force microscopy (AFM), contact angle goniometry (CAG), in vitro drug release studies, antibacterial studies and time-of-flight secondary ion mass spectrometry (ToF-SIMS)...
December 14, 2016: International Journal of Pharmaceutics
Latifa Rbah-Vidal, Aurélien Vidal, Emilie M F Billaud, Sophie Besse, Isabelle Ranchon-Cole, Florence Mishellany, Yann Perrot, Lydia Maigne, Nicole Moins, Jean-Luc Guerquin-Kern, Françoise Degoul, Jean-Michel Chezal, Philippe Auzeloux, Elisabeth Miot-Noirault
PURPOSE: This work reports, in melanoma models, the theranostic potential of ICF15002 as a single fluorinated and iodinated melanin-targeting compound. METHODS: Studies were conducted in the murine syngeneic B16BL6 model and in the A375 and SK-MEL-3 human xenografts. ICF15002 was radiolabeled with fluorine-18 for positron emission tomography (PET) imaging and biodistribution, with iodine-125 for metabolism study, and iodine-131 for targeted radionuclide therapy (TRT)...
December 14, 2016: Neoplasia: An International Journal for Oncology Research
Young-Lai Cho, Young-Pil Kim, Jin Gyeong Son, Miyoung Son, Tae Geol Lee
Protein kinases are enzymes that are important targets for drug discovery because of their involvement in regulating the essential cellular processes. For this reason, the changes in protein kinase activity induced by each drug candidate (the inhibitor in this case) need to be accurately determined. Here, an on-chip secondary ion mass spectrometry (SIMS) imaging technique of the peptides was developed for determining protein kinase activity and inhibitor screening without a matrix. In our method, cysteine-tethered peptides adsorbed onto a gold surface produced changes in the relative peak intensities of the phosphorylated and unphosphorylated substrate peptides, which were quantitatively dependent on protein kinase activity...
December 16, 2016: Analytical Chemistry
Damoon Sohrabi Baba Heidary, Clive A Randall
In previous work, it was demonstrated that using Li2CO3-coated Ni particles in the manufacturing of multilayer ceramic capacitor (MLCC) devices could improve both the permittivity and dissipation factors. However, adding Li(+) ions to the system gave rise to the concern that ions could migrate under sustained electrical fields and thereby increase the degradation rates of the insulation resistance in MLCCs. In this paper, thermally stimulated depolarization current and highly accelerated lifetime testing were both utilized to evaluate the oxygen vacancy space-charge regions and migration in MLCCs...
December 28, 2016: ACS Applied Materials & Interfaces
Frank R Moss, Steven G Boxer
The lateral organization of biological membranes is thought to take place on the nanometer length scale. However, this length scale and the dynamic nature of small lipid and protein domains have made characterization of such organization in biological membranes and model systems difficult. Here we introduce a new method for measuring the colocalization of lipids in monolayers and bilayers using stable isotope labeling. We take advantage of a process that occurs in dynamic SIMS called atomic recombination, in which atoms on different molecules combine to form diatomic ions that are detected with a NanoSIMS instrument...
December 28, 2016: Journal of the American Chemical Society
Torsten Berndt, Hartmut Herrmann, Mikko Sipilä, Markku Kulmala
The gas-phase reaction of OH radicals with isoprene has been investigated in an atmospheric pressure flow tube at 293 ± 0.5 K with special attention to the second-generation products. Reaction conditions were optimized to achieve a predominant reaction of RO2 radicals with HO2 radicals. Chemical ionization-atmospheric pressure interface-time-of-flight mass spectrometry served as the analytical technique in order to follow the formation of RO2 radicals and closed-shell products containing at least four O atoms in the molecule...
December 29, 2016: Journal of Physical Chemistry. A
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