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Secondary ion mass spectrometry

Agnieszka Priebe, Guillaume Audoit, Jean-Paul Barnes
We present a novel sample preparation method that allows correlative 3D X-ray Computed Nano-Tomography (CNT) and Focused Ion Beam Time-Of-Flight Secondary Ion Mass Spectrometry (FIB-TOF-SIMS) tomography to be performed on the same sample. In addition, our invention ensures that samples stay unmodified structurally and chemically between the subsequent experiments. The main principle is based on modifying the topography of the X-ray CNT experimental setup before FIB-TOF-SIMS measurements by incorporating a square washer around the sample...
November 19, 2016: Ultramicroscopy
Olga J G M Goor, Henk M Keizer, Anne L Bruinen, Moniek G J Schmitz, Ron M Versteegen, Henk M Janssen, Ron M A Heeren, Patricia Y W Dankers
Selective surface modification reactions can be performed on additives that are supramolecularly incorporated into supramolecular materials. Hereby, processing of the material, that regularly requires harsh processing conditions (i.e., the use of organic solvents and/or high temperatures), and functionalization can be decoupled. Moreover, high-resolution depth profiling by time-of-flight (ToF) secondary-ion mass spectrometry clearly shows distinct differences in surface and bulk material composition.
November 29, 2016: Advanced Materials
Katarzyna Gajos, Andrzej Budkowski, Varvara Pagkali, Panagiota Petrou, Monika Biernat, Kamil Awsiuk, Jakub Rysz, Andrzej Bernasik, Konstantinos Misiakos, Ioannis Raptis, Sotirios Kakabakos
The arrangement, composition and orientation of immunoreagents employed in an indirect immunoassay for determination of mycotoxin OchraToxin A (OTA) are specified for Si3N4 substrate, aiming to imitate biosensor transducers made of the same material. Si3N4 surfaces are examined after modification with (3-aminopropyl)triethoxysilane, spotting with OTA-ovalbumin conjugate (probe), blocking with bovine serum albumin, reaction with a mouse monoclonal antibody against OTA and, finally, reaction with a goat anti-mouse secondary antibody...
November 5, 2016: Colloids and Surfaces. B, Biointerfaces
Yelko Rodríguez-Carrasco, Jordi Mañes, Houda Berrada, Cristina Juan
Alternaria species are capable of producing several secondary toxic metabolites in infected plants and in agricultural commodities, which play important roles in food safety. Alternaria alternata turn out to be the most frequent fungal species invading tomatoes. Alternariol (AOH), alternariol monomethyl ether (AME), and tentoxin (TEN) are some of the main Alternaria mycotoxins that can be found as contaminants in food. In this work, an analytical method based on liquid chromatography (LC) tandem mass spectrometry (MS/MS) detection for the simultaneous quantification of AOH, AME, and TEN in tomato and tomato-based products was developed...
November 11, 2016: Toxins
Nicholas G Welch, Robert M T Madiona, Christopher D Easton, Judith A Scoble, Robert T Jones, Benjamin W Muir, Paul J Pigram
Ensuring the optimum orientation, conformation, and density of substrate-bound antibodies is critical for the success of sandwich enzyme-linked immunosorbent assays (ELISAs). In this work, the authors utilize a diethylene glycol dimethyl ether plasma polymer (DGpp) coating, functionalized with chromium within a 96 well plate for the enhanced immobilization of a capture antibody. For an equivalent amount of bound antibody, a tenfold improvement in the ELISA signal intensity is obtained on the DGpp after incubation with chromium, indicative of improved orientation on this surface...
November 10, 2016: Biointerphases
Piotr Kachlicki, Anna Piasecka, Maciej Stobiecki, Łukasz Marczak
Mass spectrometry is currently one of the most versatile and sensitive instrumental methods applied to structural characterization of plant secondary metabolite mixtures isolated from biological material including flavonoid glycoconjugates. Resolution of the applied mass spectrometers plays an important role in structural studies of mixtures of the target compounds isolated from biological material. High-resolution analyzers allow obtaining information about elemental composition of the analyzed compounds. Application of various mass spectrometric techniques, including different systems of ionization, analysis of both positive and negative ions of flavonoids, fragmentation of the protonated/deprotonated molecules and in some cases addition of metal ions to the studied compounds before ionization and fragmentation, may improve structural characterization of natural products...
November 8, 2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Elena Barbaro, Sara Padoan, Torben Kirchgeorg, Roberta Zangrando, Giuseppa Toscano, Carlo Barbante, Andrea Gambaro
The concentration and particle-size distribution of ionic species in Antarctic aerosol samples were determined to investigate their potential sources, chemical evolution, and transport. We analyzed aerosol samples collected at two different Antarctic sites: a coastal site near Victoria Land close to the Italian Research Base "Mario Zucchelli", and another site located on the Antarctic plateau, close to Italian-French Concordia Research Station. We investigated anionic compounds using ion-chromatography coupled to mass spectrometry, and cationic species through capillary ion chromatography with conductometry...
November 10, 2016: Environmental Science and Pollution Research International
Ali Rafati, Alexander G Shard, David G Castner
Gold nanoparticles (AuNPs) with average diameters of ∼14 and ∼40 nm, as well as flat gold coated silicon wafers, were functionalized with oligo ethylene glycol (OEG) terminated 1-undecanethiol (HS-CH2)11 self-assembled monolayers (SAMs). Both hydroxyl [(OEG)4OH] and methoxy [(OEG)4OMe] terminated SAMs were prepared. The AuNPs were characterized with transmission electron microscopy (TEM), time of flight secondary ion mass spectrometry (ToF-SIMS), x-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier infrared spectroscopy (ATR-FTIR), and low-energy ion scattering (LEIS)...
November 9, 2016: Biointerphases
Katarzyna Gajos, Agnieszka Kamińska, Kamil Awsiuk, Adrianna Bajor, Krzysztof Gruszczyński, Anna Pawlak, Andrzej Żądło, Artur Kowalik, Andrzej Budkowski, Ewa Stępień
Among the various biomarkers that are used to diagnose or monitor disease, extracellular vesicles (EVs) represent one of the most promising targets in the development of new therapeutic strategies and the application of new diagnostic methods. The detection of circulating platelet-derived microvesicles (PMVs) is a considerable challenge for laboratory diagnostics, especially in the preliminary phase of a disease. In this study, we present a multistep approach to immobilizing and detecting PMVs in biological samples (microvesicles generated from activated platelets and human platelet-poor plasma) on functionalized silicon substrate...
November 7, 2016: Analytical and Bioanalytical Chemistry
Fei Gao, Andrew V Teplyakov
Formation of stable organic-inorganic contacts with silicon often requires oxygen- and carbon-free interfaces. Some of the general approaches to create such interfaces rely on the formation of a Si-N bond. A reaction of dehydrohalogenation condensation of Cl-terminated Si(111) surface with phenylhydrazine is investigated as a means to introduce a simple function to the surface using a -NH-NH2 moiety as opposed to previously investigated approaches. The use of substituted hydrazine allows for the formation of a stable structure that is less strained compared to the previously investigated primary amines and leads to minimal surface oxidation...
May 17, 2016: Journal of Physical Chemistry. C, Nanomaterials and Interfaces
Gibson Gomes de Oliveira, Fausto Carnevale Neto, Daniel Pecoraro Demarque, José Antônio de Sousa Pereira-Junior, Rômulo César Sampaio Peixoto Filho, Sebastião José de Melo, Jackson Roberto Guedes da Silva Almeida, João Luiz Callegari Lopes, Norberto Peporine Lopes
The interpretation of large datasets acquired using high performance liquid chromatography coupled with tandem mass spectrometry represents one of the major challenges in natural products research. Here we propose the use of molecular networking to rapid identify the known secondary metabolites from untargeted MS/MS analysis of Adenocalymma imperatoris-maximilianii plant extracts. The leaves, stems and roots of A. imperatoris-maximilianii were extracted using different solvents according to Snyder selectivity triangle...
November 2, 2016: Planta Medica
Jeremy Bourgalais, Michael Spencer, David L Osborn, Fabien Goulay, Sebastien D Le Picard
Product detection studies of C(3P) atom reactions with butene (C4H8) isomers (but-1-ene, cis-but-2-ene, trans-but-2-ene) are carried out in a flow tube reactor at 353 K and 4 Torr under multiple collision conditions. Ground state carbon atoms are generated by 248 nm laser photolysis of tetrabromomethane, CBr4, in a buffer of helium. Thermalized reaction products are detected using synchrotron tunable VUV photoionization and time of flight mass spectrometry. The temporal profiles of the detected ions are used to discriminate products from side or secondary reactions...
October 31, 2016: Journal of Physical Chemistry. A
Bin Li, Dhaka Ram Bhandari, Andreas Römpp, Bernhard Spengler
High-resolution atmospheric-pressure scanning microprobe matrix-assisted laser desorption/ionization mass spectrometry imaging (AP-SMALDI MSI) at 10 μm pixel size was performed to unravel the spatio-chemical distribution of major secondary metabolites in the root of Paeonia lactiflora. The spatial distributions of two major classes of bioactive components, gallotannins and monoterpene glucosides, were investigated and visualized at the cellular level in tissue sections of P. lactiflora roots. Accordingly, other primary and secondary metabolites were imaged, including amino acids, carbohydrates, lipids and monoterpenes, indicating the capability of untargeted localization of metabolites by using high-resolution MSI platform...
October 31, 2016: Scientific Reports
Oscar Branson, Elisa A Bonnin, Daniel E Perea, Howard J Spero, Zihua Zhu, Maria Winters, Bärbel Hönisch, Ann D Russell, Jennifer S Fehrenbacher, Alexander C Gagnon
Plankton, corals, and other organisms produce calcium carbonate skeletons that are integral to their survival, form a key component of the global carbon cycle, and record an archive of past oceanographic conditions in their geochemistry. A key aspect of the formation of these biominerals is the interaction between organic templating structures and mineral precipitation processes. Laboratory-based studies have shown that these atomic-scale processes can profoundly influence the architecture and composition of minerals, but their importance in calcifying organisms is poorly understood because it is difficult to measure the chemistry of in vivo biomineral interfaces at spatially relevant scales...
October 28, 2016: Proceedings of the National Academy of Sciences of the United States of America
Cuiwen He, Loren G Fong, Stephen G Young, Haibo Jiang
Over the past few decades, several approaches have been used to image lipids in cells and tissues, but most have limited spatial resolution and sensitivity. Here, we discuss a relatively new approach, nanoscale secondary ion mass spectrometry imaging, that makes it possible to visualize lipids in cells and tissues in a quantitative fashion and with high spatial resolution and high sensitivity.
October 28, 2016: Journal of Investigative Medicine: the Official Publication of the American Federation for Clinical Research
Tina Bernadette Angerer, Ylva Magnusson, Goran Landberg, John Stephen Fletcher
Breast cancer is an umbrella term used to describe a collection of different diseases with broad inter- and intra-tumor heterogeneity. Understanding this variation is critical in order to develop, and precisely prescribe, new treatments. Changes in the lipid metabolism of cancerous cells can provide important indications as to the metabolic state of the cells but are difficult to investigate with conventional histological methods. Due to the introduction of new higher energy (40 kV) gas cluster ion beams (GCIBs) time-of-flight secondary ion mass spectrometry (ToF-SIMS) imaging is now capable of providing information on the distribution of hundreds of molecular species simultaneously on a cellular to sub-cellular scale...
October 26, 2016: Analytical Chemistry
Consuelo J Perez, Alessandra Tata, Michel L de Campos, Chun Peng, Demian R Ifa
Ambient mass spectrometry imaging has become an increasingly powerful technique for the direct analysis of biological tissues in the open environment with minimal sample preparation and fast analysis times. In this study, we introduce desorption electrospray ionization mass spectrometry imaging (DESI-MSI) as a novel, rapid, and sensitive approach to localize the accumulation of a mildly toxic ionic liquid (IL), AMMOENG 130 in zebrafish (Danio rerio). The work demonstrates that DESI-MSI has the potential to rapidly monitor the accumulation of IL pollutants in aquatic organisms...
October 24, 2016: Journal of the American Society for 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
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