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Registros recuperados: 6
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A mussel (Mytilus edulis) tissue certified reference material for the marine biotoxins azaspiracids ArchiMer
Mccarron, Pearse; Giddings, Sabrina D.; Reeves, Kelley L.; Hess, Philipp; Quilliam, Michael A..
Azaspiracids (AZAs) are lipophilic biotoxins produced by marine algae that can contaminate shellfish and cause human illness. The European Union (EU) regulates the level of AZAs in shellfish destined for the commercial market, with liquid chromatography-mass spectrometry (LC-MS) being used as the official reference method for regulatory analysis. Certified reference materials (CRMs) are essential tools for the development, validation, and quality control of LC-MS methods. This paper describes the work that went into the planning, preparation, characterization, and certification of CRM-AZA-Mus, a tissue matrix CRM, which was prepared as a wet homogenate from mussels (Mytilus edulis) naturally contaminated with AZAs. The homogeneity and stability of...
Tipo: Text Palavras-chave: Azaspiracids; Seafood safety; Matrix certified reference material; Liquid chromatography-mass spectrometry; Matrix effects.
Ano: 2015 URL: http://archimer.ifremer.fr/doc/00320/43138/42761.pdf
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A re-examination of matrix effects in the segmented-flow analysis of nutrients in sea and estuarine water ArchiMer
Coverly, Stephen; Kerouel, Roger; Aminot, Alain.
Modern instruments together with the use of standard reference materials have improved the accuracy and long-term reproducibility of the analysis of nutrients (ammonium, nitrate, nitrite, phosphate and silicate) in sea water using segmented-flow analysis, so that errors arising from matrix effects become more significant. Colorimetric detectors with bubble-through flowcells have become widely used for seawater analysis in recent years and their associated matrix effects are described. A re-examination of all categories of matrix effects, whose main origin is salinity, was thus undertaken to assess how much they are liable to alter the data. Interferences were classified into four types, each of which was examined in order to show its influence on the...
Tipo: Text Palavras-chave: Nutrient; Determination; Seawater; Estuarine water; Segmented-flow analysis; Matrix effects.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00057/16843/14530.pdf
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High resolution mass spectrometry for quantitative analysis and untargeted screening of algal toxins in mussels and passive samplers ArchiMer
Zendong, Suzie Zita; Mccarron, Pearse; Herrenknecht, Christine; Sibat, Manoella; Amzil, Zouher; Cole, Richard B.; Hess, Philipp.
Measurement of marine algal toxins has traditionally focussed on shellfish monitoring while, over the last decade, passive sampling has been introduced as a complementary tool for exploratory studies. Since 2011, liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been adopted as the EU reference method (No.15/2011) for detection and quantitation of lipophilic toxins. Traditional LC-MS approaches have been based on low-resolution mass spectrometry (LRMS), however, advances in instrument platforms have led to a heightened interest in the use of high-resolution mass spectrometry (HRMS) for toxin detection. This work describes the use of HRMS in combination with passive sampling as a progressive approach to marine algal toxin surveys. Experiments...
Tipo: Text Palavras-chave: Monitoring; Marine toxins; Passive sampling; SPATT; Matrix effects.
Ano: 2015 URL: http://archimer.ifremer.fr/doc/00277/38848/37388.pdf
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Hydrogen and copper isotope analysis of turquoise by SIMS: Calibration and matrix effects ArchiMer
Othmane, Guillaume; Hull, Sharon; Fayek, Mostafa; Rouxel, Olivier; Geagea, Majdi Lahd; Kyser, T. Kurtis.
The hydrogen isotope system is used extensively to provide information on the genesis of minerals (e.g., source of fluids and mechanisms of precipitation). The copper isotopic system is less well understood, but has the potential to provide valuable insight on mineral precipitation, particularly supergene Cu-rich minerals. Here we present a rapid and precise method for measuring hydrogen and copper isotopes in semi-precious gem-quality turquoise (Cu(Al,Fe3 +)6(PO4)4(OH)8 · 4H2O ) by secondary ion mass spectrometry (SIMS). The suitability of standards for instrumental mass fractionation (IMF) calibration was assessed by external precision of SIMS measurements for each standard (2-4‰ for δDIMF and 0.2-0.4‰ for δ65CuIMF). IMF in turquoise was correlated with...
Tipo: Text Palavras-chave: Turquoise; SIMS; Copper isotopes; Hydrogen isotopes; Matrix effects.
Ano: 2015 URL: https://archimer.ifremer.fr/doc/00239/35008/33546.pdf
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Investigation of the matrix effects on a HPLC-ESI-MS/MS method and application for monitoring triazine, phenylurea and chloroacetanilide concentrations in fresh and estuarine waters ArchiMer
Mazzella, N.; Delmas, F.; Delest, B.; Mechin, B.; Madigou, C.; Allenou, Jean-pierre; Gabellec, Raoul; Caquet, Th..
In this work, the effects of matrix interferences on the analytical performance of a new multiresidue method based on off-line solid phase extraction followed by reversed-phase liquid chromatographic separation and electrospray triple quadrupole mass spectrometric detection were investigated. This technique allows the simultaneous determination of 30 triazines, phenylureas and chloroacetanilides, extracted from freshwaters, in 40 minutes. Quantifications were performed with the use of appropriate internal standards (i.e. atrazine D5, diuron D6 and metolachlor D6). The limits of quantification were from 1 to 32 ng L-1 for the triazines, from 5 to 59 ng L-1 for the phenylureas and from 13 to 54 ng L-1 for the chloroacetanilides. The matrix effects were...
Tipo: Text Palavras-chave: River estuarine interface; Natural water quality; Herbicides; Matrix effects; Multiresidue method; HPLC ESI MS/MS.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/2009/publication-6092.pdf
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Quantitative analysis of azaspiracids in Azadinium spinosum cultures ArchiMer
Jauffrais, Thierry; Herrenknecht, Christine; Sechet, Veronique; Sibat, Manoella; Tillmann, Urban; Krock, Bernd; Kilcoyne, Jane; Miles, Christopher O.; Mccarron, Pearse; Amzil, Zouher; Hess, Philipp.
Azaspiracids (AZAs) are secondary metabolites of Azadinium spinosum, that have been shown to cause diarrhetic shellfish poisoning when accumulated in bivalve molluscs. We describe here an analytical procedure for the determination of AZAs in cultures of A. spinosum with a focus on the potential formation of AZA methyl-esters as artefacts in the extraction and sample pre-treatment. A. spinosum cells were collected from bioreactor cultures, using centrifugation or filtration. Different extraction procedures were evaluated for formation of methyl-ester artefacts, yield, and matrix effects. Filtration of cultures using glass-fibre filters led to increased formation of methyl-esters. Hence centrifugation is recommended for recovery of cells. The type of...
Tipo: Text Palavras-chave: Extraction procedure; Extraction artefact; Matrix effects; LC-MS/MS; Azaspiracid methyl ester; Dinoflagellate; Liquid chromatography-mass spectrometry.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00077/18812/16463.pdf
Registros recuperados: 6
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