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Malgré les récentes régulations sur la production et l’utilisation de substances polyfluorées, ces composés persistants sont de nos jours ubiquitaires dans les milieux aquatiques, et ce même dans des endroits isolés tels les Iles Féroé.
Ce mémoire a pour but d’observer l’évolution de la contamination par 18 PFAS d’une population d’Ombles Chevaliers (Salvelinus Alpinus) d’un lac isolé situé sur l’île de Streymoy aux Iles Féroé. Ce lac est (à notre connaissance) exempt de toute contamination anthropogénique directe.
Les échantillons (muscles prélevés sur le filet droit) ont été analysés à l’aide d’une chromatographie en phase liquide et d’un spectromètre de masse.
Les résultats auraient du être mis en relation avec des données météorologiques du Landversk ; le transport par voie aérienne et les dépositions humides étant les voies de contaminations principales suspectées, ceci aurait pu permettre de voir si la contamination des poissons suit effectivement l’évolution des précipitations.
Les précipitations variant énormément d’un endroit à l’autre au sein des Iles Féroé, des échantillons d’eau ont été prélevés dans 9 lacs. Ceux-ci ont été concentrés et nettoyés via extraction en phase solide et auraient du être analysés par UPLC et MS. Les résultats auraient été mis en parallèle avec des données météo afin de voir si la contamination des lacs semble suivre les différents taux de précipitations.
Suite à un problème technique (une pompe de l’UPLC n’est plus fiable), les échantillons d’eau n’ont pas pu être analysés. Les analyses des échantillons de poissons sont quant à elles non fiables.
Les conclusions, basées sur des résultats non fiables, sont que les concentrations de PFAS étaient croissantes jusqu’à 2009 et semblent diminuer à partir de 2011. Aucune donnée météo n’était disponible jusqu’à 2006, et les données pour la période 2006-2009 se sont avérées inexploitables. Restent donc 2010 à 2014, mais les échantillons de poisson analysés datent de 2011 au plus tard ; les résultats n’ont donc pas pu être mis en lien. Despite the increasing number of regulations on the production and uses of polyfluorinated substances, those persistent compounds are nowadays ubiquitous in marine environments, even in remote places such as the Faroe Islands.
This master thesis aimed to establish a time trend of 18 different PFAS in a population of Arctic chars (Salvelinus Alpinus) from Lake á Mýrunum from 2000 until 2014. This small lake is located on the island of Streymoy and is isolated from direct anthropogenic contamination.
The fish samples (right filet muscle) were prepared specifically for this purpose and analysed using an Ultra Performance Liquid Chromatograph and a tandem mass spectrometer.
The results would then be put in relation with meteorological data from Landversk, as atmospheric transport and wet depositions are suspected to be the main source of PFAS in the Faroe Islands, especially in places as isolated as Lake á Mýrunum. This would have allowed seeing whether the evolution of PFAS contamination in fishes seems to follow the precipitations.
Since precipitations in the Faroe Islands vary greatly from a place to another, nine lake were sampled. Those samples werre prepared using Solid Phase Extraction and would have been analysed for PFAS contamination in the water. The results would have been related to meteorological data to see whether lake water contamination is directly dependent of rain.
Due to technical issues (a pump from the UPLC failed), no lake water samples were analysed, and most of the fish sample analyses failed.
The conclusions, based on unreliable results, are that PFAS’s concentration in fishes tend to increase until 2009 before starting to decrease in 2011. The meteo data turned out being unexploitable for the 2006-2009 period and the data from before 2006 could not be retrieved. The few results of the fish analyses could therefore not be related to the meteorological data.

substances polyfluorées (PFAS) --- dépositions humides --- PFOS/PFOSA --- Ultra Performance Liquid Chroamtography (UPLC) --- Spectrométrie de Masse (MS) --- Extraction en Phase Solide (SPE) --- alkyl substances (PFAS) --- wet depositions --- PFOS/PFOSA --- remote environment --- Ultra Performance Liquid Chroamtography (UPLC) --- Mass Spectrometry (MS) --- Solid Phase Extraction (SPE) --- Sciences du vivant > Sciences de l'environnement & écologie

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extractie --- chromatografie --- Fysicochemical separation methods --- Extraction (Chemistry) --- 66.061.3 --- 664 --- 543.8 --- 57.088 --- Chemistry, Technical --- Diffusion --- Packed towers --- Separation (Technology) --- Solution (Chemistry) --- Extraction (selective solution) --- Production and preservation of solid foodstuffs --- Analysis of organic substances --- Special methods and techniques for studing biological molecules. Separation. Centrifuging. X-ray study. Radioisotope methods --- Extraction (Chemistry). --- 57.088 Special methods and techniques for studing biological molecules. Separation. Centrifuging. X-ray study. Radioisotope methods --- 543.8 Analysis of organic substances --- 664 Production and preservation of solid foodstuffs --- 66.061.3 Extraction (selective solution) --- SPE (solid phase extraction)

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In dit boek worden alle recente ontwikkelingen op het gebied van levensmiddelenanalyses behandeld. Bij de staalvoorbereiding zijn deze ontwikkelingen onder meer een gevolg van steeds lagere concentraties van te bepalen bestanddelen, complexere matrices, milieuaspecten voor gebruikte oplosmiddelen en de reeds aangehaalde strengere normen opgelegd door de overheden. Er wordt dus gestreefd naar nauwkeuriger resultaten in kortere tijd en met minder kosten. Bij de eigenlijke analyse is het principe in heel wat gevallen een chromatografrische scheiding. Andere analysemethoden zijn vloeistofinjectieanalyse en capillaire elektroforese. Verder zijn er ook de biotechnologische methoden.Bij de detectie, dit is het kwantificeren van de afzonderlijke bestanddelen, zijn er eveneens heel wat recente ontwikkelingen. Elementen die daarbij spelen zijn miniaturisering en automatisering. Een trend tegenwoordig is het combineren van twee of meer analysetechnieken.

spectrometrie --- DNA (deoxyribonucleic acid) --- voeding --- Applied chemical analysis --- Nutritionary hygiene. Diet --- Biotechnology --- voedingschemie --- Spectrometric and optical chemical analysis --- fysicochemie --- Physicochemistry --- analyse (chemie) --- biotechnologie --- Fysicochemical separation methods --- Alimentation --- Biochemie --- Biochimie --- Voeding --- Kwaliteitszorg ; voedingsmiddelen --- 641 --- analysemethoden 543 --- voeding 641./.3 --- voedingsleer --- 543 --- 641.1 --- 664 --- analytische chemie (scheikunde) --- voedingsmiddelenchemie --- 543.06 --- Chromatografie --- Elektroferese --- Elektroforese --- Gaschromatografie --- Massaspectrometrie --- Voedingsmiddelenanalyse --- 614.4 --- ASE --- Analyse (chemie) --- Capillaire elektroforese --- DNA --- Detectie --- FIA --- GC --- HPLC --- IAC --- Immunochemie --- LC --- LLE --- MSPD --- MWAE --- SBSE --- SFE --- SPME --- Solid phase extraction --- TLC --- Tuinbouw (lt) --- UAE --- Voeding (lt) --- Voedingsmiddelentechnologie --- biotechnologie (lt) --- microbiologie (lt) --- 664.4 --- Voeding : analysemethoden --- R04625.jpg --- Voeding. Voedsel--(zie ook {392.8}) --- analytische chemie (analytische scheikunde) --- levensmiddelen --- oplosmiddelen --- chromatografie --- levensmiddelentechnologie --- departement Biotechniek --- opleiding biotechnologie --- 642

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Sample preparation is and will always be the most important step in chemical analysis. Numerous techniques, methods, methodologies, and approaches are published in the literature offering a wide range of analytical tools to the lab practitioner. Analytical scientists all over the world are trying to develop protocols for a plethora of analytes in various sample matrices. In the last decade, sample pre-treatment advances have followed green chemistry and green analytical chemistry demands, focusing on miniaturization and automation, using the least possible amount of organic solvents. The question is how far we have been till now, and what the future perspectives are. To answer this question, analytical chemists were invited to share their experience in the field and report on the recent advances in sample-preparation approaches. The outcome of our invitation was eleven excellent manuscripts, including four review articles and seven original research articles in the first edition of the Special Issue “Sample Preparation-Quo Vadis: Current Status of Sample Preparation Approaches”.The second edition is a collection of ten significant contributions to the field of sample preparation. It includes two highly interesting and comprehensive review articles and eight innovative research articles.

Research & information: general --- Chemistry --- Analytical chemistry --- sample preparation --- matrix solid-phase dispersion --- salting-out --- homogenous liquid-liquid extraction --- bisphenol --- bee pollen --- tricyclic antidepressants --- urine samples --- bar adsorptive microextraction (BAμE) --- novel sorbent phases --- biomaterials waste --- flotation sampling technology --- GC-MS --- amino acids --- chocolate --- derivatization --- HPLC --- fluorescence --- automation --- flow injection --- inductively coupled plasma --- sol-gel --- solid-phase extraction --- metals --- molecular imprinted polymer --- interaction mechanism --- template-monomer interaction --- MIP-template interaction --- microwave-assisted extraction --- tocopherols --- phenolics --- flavonoids --- authenticity --- HPLC-UV --- bismuth oxide --- API particle size --- API morphology --- film-coated tablets --- Raman spectroscopy --- ImageJ --- tablet disintegration --- green extraction techniques --- microextraction techniques --- biological samples --- food samples --- environmental samples --- carbaryl --- cassia bark (Senna siamea Lam.) --- smartphone-based digital image analysis --- 1-naphthol --- peroxidase enzyme --- raman spectroscopy --- carriers --- sample holders --- gold layer --- cuvette --- ethanol --- urine --- volatile compounds --- biological fluids --- n/a

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Five years of Separations are celebrated by a collection of ten feature articles: one review and nine research articles on topics of current interest. Applications of Gas Chromatography for the Analysis of Tricyclic Antidepressants in Biological Matrices are presented focusing on novel extraction techniques and novel materials used for sample preparation due to the great demand for method development for the determination of TCAs in biofluids, especially for therapeutic drug monitoring. Original research articles include the following: 1. Insights into the Mechanism of Separation of Bisphosphonates by Zwitterionic Hydrophilic Interaction Liquid Chromatography: Application to the Quantitation of Risedronate in Pharmaceuticals. 2. A method based on micro-matrix solid-phase dispersion (μ-MSPD) followed by gas-chromatography tandem mass spectrometry (GC–MS/MS), developed to analyze UV filters in personal care products. 3. The performance of a vibratory shear-enhanced process (VSEP) combined with an appropriate membrane unit for the treatment of simulated or industrial tannery wastewaters. 4. A method for the analysis of thyroid hormones by liquid chromatography-mass spectrometry that was used for the dissolution testing of single- and dual-component thyroid hormone supplements via a two-stage biorelevant dissolution procedure. 5. A method involving the collection and determination of organic and inorganic gunshot residues on hands using online in-tube solid-phase microextraction (IT-SPME) coupled to miniaturized capillary liquid chromatography with diode array detection (CapLC-DAD) and scanning electron microscopy coupled to energy dispersion X-ray (SEM-EDX), respectively, for quantifying both residues. 6. The gas chromatographic retention behavior of 16 polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs on a new ionic liquid stationary phase, 1,12-di(tripropylphosphonium) dodecane bis(trifluoromethanesulfonyl)imide (SLB®-ILPAH) intended for the separation of PAH mixtures, which was compared with the elution pattern on more traditional stationary phases: a non-polar phenyl arylene (DB-5ms) and a semipolar 50% phenyl dimethyl siloxane (SLB PAHms) column. 7. The Multiple-Stage Precursor Ion Separation and High Resolution Mass Spectrometry toward Structural Characterization of 2,3-Diacyltrehalose Family from Mycobacterium tuberculosis 8. The use of micellar electrokinetic chromatography (MEKC) for studying the hydrophobic character of modified Monomethyl Auristatin E derivatives, as Novel Candidates for the Design of Antibody–Drug Conjugates, which are promising state-of-the-art biopharmaceutical drugs for selective drug-delivery applications and the treatment of diseases such as cancer. 9. The use of recycled diatomaceous earth as the extraction phase in solid phase microextraction (SPME) technique for the determination of polycyclic aromatic hydrocarbons (PAHs) in river water samples, with separation/detection performed by gas chromatography-mass spectrometry (GC-MS).

Research & information: general --- recycled diatomaceous earth --- solid phase microextraction --- polycyclic aromatic hydrocarbons --- gas chromatography-mass spectrometry --- antibody-drug conjugate --- biopharmaceutical --- cytotoxicity --- hydrophobicity --- micellar electrokinetic chromatography --- tandem mass spectrometry --- linear ion trap --- glycolipid --- diacyltrehalose --- Mycobacterium tuberculosis --- bisphosphonates --- risedronate --- zoledronate --- tiludronate --- ZIC-HILIC --- PDA --- quantitation --- tablets --- ionic liquid stationary phase --- gas chromatography --- chromatographic selectivity --- alkylated polycyclic aromatic hydrocarbons (alkylated PAHs) --- diphenylamine --- gunshot residues --- hands --- dry cotton swab --- in-tube solid-phase extraction --- capillary liquid chromatography --- SEM-EDX --- thyroid --- dissolution --- liquid chromatography-mass spectrometry --- membrane filtration-treatment --- membrane type-operation --- membrane fouling mechanism --- tannery industrial wastewater --- vibratory shear-enhanced process (VSEP) --- tricyclic antidepressants (TCAs) --- sample treatment --- biological fluids --- UV filters --- matrix solid-phase dispersion --- μ-MSPD --- miniaturized extraction technique --- GC–MS/MS --- cosmetic analysis --- personal care products --- fragrance allergens --- preservatives --- plasticizers --- synthetic musks