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Secondary ion mass spectrometry

Canan Turgut, Godhuli Sinha, Jouko Lahtinen, Kai Nordlund, Mohammed Belmahi, Patrick Philipp
Quantitative analyses in secondary ion mass spectrometry (SIMS) become possible only if ionization processes are controlled. The Storing Matter technique has been developed to circumvent this so-called matrix effect, primarily for inorganic samples, but has also been extended to organic samples. For the latter, it has been applied to polystyrene in order to investigate the extent of damage in the polymer, its fragmentation during the sputter deposition process and the effect of the deposition process on the spectra taken by Time-of-Flight SIMS (ToF-SIMS)...
October 2016: Journal of Mass Spectrometry: JMS
Veronika Metlenko, WooChul Jung, Sean R Bishop, Harry L Tuller, Roger A De Souza
Oxygen transport in the mixed ionic-electronic conducting perovskite-oxides SrTi1-yFeyO3-δ (with y = 0.5 and y = 1.0) was studied by oxygen isotope exchange measurements. Experiments were performed on thin-film samples that were grown by Pulsed Laser Deposition (PLD) on MgO substrates. Isotope penetration profiles were introduced by (18)O2/(16)O2 exchanges into the plane of the films at various temperatures in the range 773 < T/K < 973 at an oxygen activity aO2 = 0.5. Isotope profiles were determined subsequently by Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS), and their analysis yielded tracer diffusion coefficients D* and oxygen surface exchange coefficients k*...
October 17, 2016: Physical Chemistry Chemical Physics: PCCP
Jabadurai Jayapaul, Susanne Arns, Matt Bunker, Marek Weiler, Sandra Rutherford, Peter Comba, Fabian Kiessling
: Riboflavin (Rf) receptors bind and translocate Rf and its phosphorylated forms (e.g. flavin mononucleotide, FMN) into cells where they mediate various cellular metabolic pathways. Previously, we showed that FMN-coated ultrasmall superparamagnetic iron oxide (FLUSPIO) nanoparticles are suitable for labeling metabolically active cancer and endothelial cells in vitro. In this study, we focused on the in vivo application of FLUSPIO using prostate cancer xenografts. Size, charge, and chemical composition of FLUSPIO were evaluated...
2016: Nano Research
Cosima Damiana Calvano, Giovanni Ventura, Massimo Trotta, Giuliana Bianco, Tommaso R I Cataldi, Francesco Palmisano
Bacteriochlorophyll a (BChl a), a photosynthetic pigment performing the same functions of chlorophylls in plants, features a bacteriochlorin macrocycle ring (18 π electrons) with two reduced pyrrole rings along with a hydrophobic terpenoid side chain (i.e., the phytol residue). Chlorophylls analysis by matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) is not so straightforward since pheophytinization (i.e., release of the central metal ion) and cleavage of the phytol-ester linkage are invariably observed by employing protonating matrices such as 2,5-dihydroxybenzoic acid, sinapinic acid, and α-cyano-4-hydroxycinnamic acid...
October 11, 2016: Journal of the American Society for Mass Spectrometry
Jean-Luc Vorng, Anna M Kotowska, Melissa K Passarelli, Andrew West, Peter S Marshall, Rasmus Havelund, Martin P Seah, Colin T Dollery, Paulina D Rakowska, Ian S Gilmore
There is an increasing need in the pharmaceutical industry to reduce drug failure at late stage and so reduce the cost of developing a new medicine. Since most drug targets are intracellular this requires a better understanding of the drug disposition within a cell. Secondary ion mass spectrometry has been identified as a potentially important technique to do this as it is label-free and allows imaging in 3D with sub-cellular resolution and recent studies have shown promise for amiodarone. An important analytical parameter is sensitivity and we measure this in a bovine liver homogenate reference sample for twenty drugs representing important class-types relevant to the pharmaceutical industry...
October 11, 2016: Analytical Chemistry
Anton V Ievlev, Petro Maksymovych, Morgan Trassin, Jan Seidel, Ramamoorthy Ramesh, Sergei V Kalinin, Olga S Ovchinnikova
Domain formation and ferroelectric switching is fundamentally inseparable from polarization screening, which on free surfaces can be realized via band bending and ionic adsorption. In the latter case, polarization switching is intrinsically coupled to the surface electrochemical phenomena, and the electrochemical stage can control kinetics and induce long-range interactions. However, despite extensive evidence towards the critical role of surface electrochemistry, little is known about the nature of the associated processes...
October 11, 2016: ACS Applied Materials & Interfaces
Nicholas G Welch, Robert M T Madiona, Judith A Scoble, Benjamin W Muir, Paul J Pigram
Antibody denaturation at surface-liquid interfaces plays an important role in the sensitivity of protein assays such as enzyme-linked immunosorbent assays (ELISAs). Surface immobilized antibodies must maintain their native state, with their antigen binding (Fab) region intact, to capture antigens from biological samples and permit disease detection. In this work, two identical sample sets were prepared with whole antibody IgG, F(ab')2 and Fc fragments, immobilized to either a silicon wafer, or a diethylene glycol dimethyl ether plasma polymer surface...
October 7, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
Yuanzhao Ding, Yufan Zhou, Juan Yao, Craig Szymanski, James K Fredrickson, Liang Shi, Bin Cao, Zihua Zhu, Xiao-Ying Yu
Molecular mapping of live biofilms at submicron resolution presents a grand challenge. Here, we present the first chemical mapping results of biofilm extracellular polymeric substance (EPS) components in biofilms using correlative imaging be-tween super resolution florescence microscopy and liquid time-of-flight secondary ion mass spectrometry (ToF-SIMS). She-wanella oneidensis is used as a model organism. Heavy metal anions chromate (Cr2O72-) consisting of chromium Cr (VI) was a model environmental stressor used to treat the biofilms...
October 6, 2016: Analytical Chemistry
Jeannine Hess, Malay Patra, Loganathan Rangasamy, Sandro Konatschnig, Olivier Blacque, Abdul Jabbar, Patrick Mac, Erik M Jorgensen, Robin B Gasser, Gilles Gasser
The discovery of novel drugs against animal parasites is in high demand due to drug-resistance problems encountered around the world. Herein, the synthesis and characterization of 27 organic and organometallic derivatives of the recently launched nematocidal drug monepantel (Zolvix(®) ) are described. The compounds were isolated as racemates and were characterized by (1) H, (13) C, and (19) F NMR spectroscopy, mass spectrometry, and IR spectroscopy, and their purity was verified by microanalysis. The molecular structures of nine compounds were confirmed by X-ray crystallography...
October 5, 2016: Chemistry: a European Journal
J Bobrowska, J Moffat, K Awsiuk, J Pabijan, J Rysz, A Budkowski, M Reading, M Lekka
Various techniques have been already reported to differentiate between normal (non-malignant) and cancerous cells based on their physico-chemical properties. This is relatively simple when studied cancerous cells originate from distant stages of cancer progression. Here, studies on chemical properties of two closely related human melanoma cell lines are presented: WM115 melanoma cells were taken from the vertical growth phase while WM266-4 from the skin metastatic site of the same patient. Their chemical properties were studied by two techniques, namely time-of-flight secondary ion mass spectra (ToF SIMS) and photothermal microspectroscopy (PTMS), used to record mass and photothermal spectra of cells, respectively...
September 16, 2016: Analyst
I Klawonn, N Nahar, J Walve, B Andersson, M Olofsson, B J Svedén, S Littmann, M J Whitehouse, Mmm Kuypers, H Ploug
We analysed N2 - and carbon (C) fixation in individual cells of Baltic Sea cyanobacteria by combining stable isotope incubations with secondary ion mass spectrometry (SIMS). Specific growth rates based on N2 - and C-fixation were higher for cells of Dolichospermum spp. than for Aphanizomenon sp. and Nodularia spumigena. The cyanobacterial biomass, however, was dominated by Aphanizomenon sp., which contributed most to total N2 -fixation in surface waters of the Northern Baltic Proper. N2 -fixation by Pseudanabaena sp...
October 1, 2016: Environmental Microbiology
Pierre Le Pogam, Anne-Cécile Le Lamer, Béatrice Legouin, Joël Boustie, David Rondeau
INTRODUCTION: Lichens widely occur all over the world and are known to produce unique secondary metabolites with various biological activities. OBJECTIVE: To develop high-throughput screening approaches requiring little to no sample preparation to alleviate the dereplication holdup and accelerate the discovery workflow of new structures from lichens. METHODOLOGY: The extracellular distribution of lichen metabolites is incentive for in situ chemical profiling of lichens using the ambient mass spectrometry DART-MS...
November 2016: Phytochemical Analysis: PCA
Mai Yamamoto, Ritchie Ly, Biban Gill, Yujie Zhu, Jose Moran-Mirabal, Philip Britz-McKibbin
Capillary electrophoresis-mass spectrometry (CE-MS) represents a high efficiency microscale separation platform for untargeted profiling of polar/ionic metabolites that is ideal for volume-restricted biological specimens with minimal sample workup. Despite these advantages, the long-term stability of CE-MS remains a major obstacle hampering its widespread application in metabolomics notably for routine analysis of anionic metabolites under negative ion mode conditions. Herein, we report for the first time that commonly used ammonia containing buffers compatible with electrospray ionization (ESI)-MS can compromise the integrity of fused-silica capillaries via aminolysis of their outer polyimide coating...
October 10, 2016: Analytical Chemistry
Katarzyna Gajos, Vitaliy A Guzenko, Matthias Dübner, Jakub Haberko, Andrzej Budkowski, Celestino Padeste
Well-defined submicrometer structures of poly(dimethylaminoethyl methacrylate) (PDMAEMA) were grafted from 100 μm thick films of poly(ethene-alt-tetrafluoroethene) after electron-beam lithographic exposure. To explore the possibilities and limits of the method under different exposure conditions, two different acceleration voltages (2.5 and 100 keV) were employed. First, the influence of electron energy and dose on the extent of grafting and on the structure's morphology was determined via atomic force microscopy...
October 7, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
Andreas Pelster, Martin Körsgen, Takako Kurosawa, Hiromi Morita, Heinrich F Arlinghaus
Heterogeneous polymer coatings, such as those used in organic electronics and medical devices, are of increasing industrial importance. In order to advance the development of these types of systems, analytical techniques are required which are able to determine the elemental and molecular spatial distributions, on a nanometer scale, with very high detection efficiency and sensitivity. The goal of this study was to investigate the suitability of laser postionization secondary neutral mass spectrometry (Laser-SNMS) with a 157 nm postionization laser beam to image structured polymer mixtures and compare the results with time-of-flight secondary ion mass spectrometry (ToF-SIMS) measurements using Bi3(+) primary ions...
October 4, 2016: Analytical Chemistry
Lara J Gamble, Christopher R Anderton
Secondary ion mass spectrometry (SIMS) is a technique capable of imaging tissues, single cells, and microbes revealing chemical species with sub-micrometer spatial resolution. The recently developed Fourier transform ion cyclotron resonance (FTICR) SIMS instrument provides high mass resolving power and mass accuracy, ToF-SIMS can generate chemical maps with an order of magnitude better lateral resolution than the FTICR-SIMS, and the NanoSIMS instrument offers sub-100 nm spatial resolution in chemical imaging...
March 2016: Microscopy Today
Kendra J Adams, John Daniel DeBord, Francisco Fernandez-Lima
In the present work, the emission characteristics of lipids as a function of the primary ion cluster size and energy were studied using time-of-flight secondary ion mass spectrometry (TOF-SIMS). Characteristic fragmentation patterns for common lipids are described, and changes in secondary ion (SI) yields using various primary ion beams are reported. In particular, emission characteristics were studied for pairs of small polyatomic and nanoparticle primary ion beams (e.g., Bi3 (+) versus Ar1000 (+) and Au3 (+) versus Au400 (+4)) based on the secondary ion yield of characteristic fragment and intact molecular ions as a function of the lipid class...
September 2016: Journal of Vacuum Science and Technology. B, Nanotechnology & Microelectronics: Materials, Processing, Measurement, & Phenomena: JVST B
Babak Basiri, Hilde van Hattum, William D van Dongen, Mandi M Murph, Michael G Bartlett
Hexafluoroisopropanol (HFIP) has been widely used as an acidic modifier for mobile phases for liquid chromatography-mass spectrometry (LC-MS) analysis of oligonucleotides ever since the first report of its use for this purpose. This is not surprising, considering the exceptional performance of HFIP compared with carboxylic acids, which cause significant MS signal suppression in electrospray ionization. However, we have found that other fluorinated alcohols can also be utilized for mobile phase preparation and the choice of optimal fluorinated alcohol is determined by the ion-pairing (IP) agent...
September 19, 2016: Journal of the American Society for Mass Spectrometry
Kamil Awsiuk, Andrzej Budkowski, Panagiota Petrou, Mateusz M Marzec, Monika Biernat, Teresa Jaworska-Gołąb, Jakub Rysz
Many of bioelectronic and biosensor applications are based on poly(3-alkylthiophenes), conducting and solution-processable polymers. The most facile approach for the fabrication of such devices relies on biofunctionalization of P3AT surfaces with antibodies through adsorption. The success of this approach depends critically on antibody orientation that affects its biorecognition. As demonstrated here both these features are controlled by the surface structure of spin-cast P3ATs. In particular, a multi-technique and multivariate study that involved Atomic Force Microscopy, Grazing Incidence X-ray Diffraction, Angle-Resolved X-ray Photoelectron Spectroscopy, Enzyme-Linked ImmunoSorbent Assay, and Time-of-Flight Secondary Ion Mass Spectrometry combined with Principal Component Analysis is conducted in order to deduce the crystalline texture of three P3AT polymers as well as its effect on orientation of adsorbed rabbit immunoglobulin (IgG) molecules...
August 20, 2016: Colloids and Surfaces. B, Biointerfaces
Shigeto Okuji, Hideaki Kitazawa, Yoshihiko Takeda
We investigated the effects of nanoscopic surface modification of polyvinylidene difluoride (PVDF) and low-density polyethylene (LDPE) by plasma-based ion implantation on protein adsorption with time of flight-secondary ion mass spectrometry (ToF-SIMS) analysis. The chemical composition of the LDPE and PVDF surfaces was changed by ion irradiation. In particular, irradiation substantially decreased the number of CH and CF bonds on the PVDF surface, but only slightly decreased that of CH bonds for LDPE. These decreases may reflect a higher hydrogen recombination rate of the LDPE than the PVDF surface...
August 20, 2016: Colloids and Surfaces. B, Biointerfaces
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