Tesi sul tema "Chromatographie phase liquide spectrométrie de masse"
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Himbert, Franck. "Purification d'un mélange multicomposés en chromatographie liquide préparative : colonne, injection & couplage à la spectrométrie de masse". Orléans, 2003. http://www.theses.fr/2003ORLE2042.
Wolters, Cédric. "Caractérisation moléculaire d’échantillons organiques complexes par spectrométrie de masse et chromatographie en phase liquide". Thesis, Université Grenoble Alpes, 2021. http://www.theses.fr/2021GRALU009.
How to analyse a complex organic sample? This general question seems simple at first glance but requires a closer look at the notion of complexity to be able to understand and justify the means used to characterise it. In planetology, and more widely in astrophysics, all the observations and observables indicate that the matter that makes up extraterrestrial objects is composed of a mixture of various molecules, and this mixture is more or less diverse and dense depending on the object. Observations and models are routinely done to try to understand these objects and to constrain their evolutionary processes, or to try to investigate their origin.Characterising the molecular complexity of such objects requires state-of-the-art instruments, which are difficult to adapt to space industry constraints in order to be placed on a probe, and this requires that the object under study can be sampled. However, most objects of interest cannot be reached in a reasonable time. Therefore, another way to study these objects is needed: laboratory astrophysics. Many experiments attempt to simulate the objects and environments in which they evolve and analyse the evolution of matter subjected to these constraints. Part of the challenges of these experiments lies in the chemical characterisation of the samples, and more particularly in their molecular characterisation.As part of this thesis, we proposed to use high-resolution mass spectrometry (HRMS) and high-performance liquid chromatography (HPLC) to characterise complex organic samples. To do so, the entire analytical chain was studied, from the data acquisition to its use. Thus, we proposed an optimisation of the data acquisition in Orbitrap, as well as the systematic processing of the data resulting from the analysis done by ESI-HRMS as well as for the analysis done by LDI-ICR. Chromatography coupled with mass spectrometry is a powerful tool for accessing the molecular structure of samples and requires developing methods that are suited to the samples analysed. Therefore we offered two HPLC methods for sample analysis, which have been developed and validated for the analysis of complex samples. However, no currently available commercial software allowed for the unsupervised analysis of such samples. Software to allow the processing of this data has now been developed and allows the molecular diversity of samples to be revealed without supervision. The identification of the detected molecules is not an easy process since it then requires having all the possible isomers for each molecule detected as standards for reference. To reduce the number of possibilities, a tool for predicting retention times was proposed. This was based on knowledge of the physico-chemical properties of known compounds to predict their theoretical retention time on the methods used.Lastly, this work presents the application of all the developments carried out during these three years on a set of samples of synthetic atmospheric aerosol analogues modelling exoplanets of the super-Earth and mini-Neptunes type. From the analysis of their soluble matter to the comparison between soluble, insoluble, and total phase, analysis by mass spectrometry indicates a great diversity and important differences between samples. This indicates processes of formation and evolution related to the composition of the reactive mixture. Finally, chromatographic analysis of one of these samples indicates multiple isomers, some of which may be labelled as biological molecules, potentially involved in the process of the origin of life
Dufour, Alizée. "Caractérisation des tensioactifs polydisperses industriels par spectrométrie de masse et chromatographie en phase liquide". Thesis, Université Paris sciences et lettres, 2020. http://www.theses.fr/2020UPSLS019.
IIn the petroleum industry, surfactant formulation is becoming more and more complex, especially in thecase of Enhanced Oil Recovery. Analytical challenges therefore appear when monitoring these surfactants.After a detailed characterisation using high resolution mass spectrometry (HRMS), a preliminary studyallowed a better understanding of the chomatographic behaviours of surfactants on different stationnaryphases. A screening of nine different columns showed that LC-1D separation did not result in a completeseparation due to the range of polarities and the polydispersity of the compounds. However, thedevelopment of a multi-dimensional approach solved the co-eluting observed in LC-1D. Following this proofof concept, the determination of the response factor, using charged aerosol detection, underlined the lackof a uniform response within a distribution. This has a strong impact on the mass balance. Finally, theinfluence of the presence of oil was demonstrated by studying a mixture of anionic and nonionic surfactantsin oil matrix. The separation was maintained but the presence of organic solvent and crude oil has a crucialimpact on the signal
Roy, Sylvie. "Couplage de la chromatographie liquide haute performance et de la spectrométrie de masse". Paris 5, 1989. http://www.theses.fr/1989PA05P035.
Jeudy, Jérémy. "Quantification de biomarqueurs protéiques dans des matrices biologiques complexes par spectrométrie de masse : développements et applications". Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10242/document.
Over the past decade, interest in the use of biomarkers in clinical studies has greatly increased. Quantification of a candidate protein biomarker in complex samples (eg. plasma) requires targeted and multiplexed assays. Immunoassays are the gold standard for their quantification. However, with the need for targeted and multiplexed methods, recent developments in mass spectrometry (MS) make a viable alternative to ELISA. The present work has addressed the problems encountered in this type of proteomic studies, and solutions that can be explored to improve the workflow of candidate biomarker’s evaluation. Methionine peptides are generally avoided due to their susceptibility to oxidation. However, it seemed interesting to study how their endogenous modifications could affect biological processes. In a first time, apolipoproteins were dismissed as a potential biomarker of Alzheimer’s disease due to oxidation impact. In the same time, problems associated with biological sample collection and storage were highlighted. DBS (Dried Blood Spot) and Vivid device evaluation from a panel of 32 blood proteins has provided a first possible solution to overcome these troubles. Thereafter, a new peptide quantification method called MRM3 was used to overcome biological matrix complexity. Reliable level determinations of 2 plasma proteins (C-Reactive protein and TIMP-1) and 2 urinary proteins (aquaporin-2 and podocin) were obtained. To improve sensitivity and reduce analysis solvent costs, performances of a micro chromatography platform were compared to a narrow-bore platform. This study highlighted the significant impact of the matrix effect on the analytical process, requiring new strategie development. Finally, to reduce sample complexity, evaluation of wide pore solid-phase extraction cartridges has been achieved. A protocol was successfully developed to analyze enzymes contained in commercial laundry samples. Finally to optimize biological sample preparation time, heated-assisted digestion and online desalting step were successfully associated. Only few hours were then required for quantitative analysis
Rougemont, Blandine. "Quantification de protéines dans des matrices complexes par spectrométrie de masse : nouveaux outils et apllications". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1084/document.
Tandem mass spectrometry is now a technique of choice for human or micro-organisms proteome analysis. Typically, proteins are first digested into surrogates’ peptides, separated by liquid chromatography before being analyzed by MS/MS. The ultimate goal is the identification and the quantification of these peptides, belonging to proteins and highlighting a phenotype or a cellular mechanism in a complex organism. Both targeted and untargeted approaches are used and are complementary in proteomic analysis. The work presented here is focused on the development of targeted methods, and more particularly in the SRM mode, through two applications involving micro-organisms. So, the first study concerned to absolute quantification of viral proteins of the chimeric yellow-dengue fever, vaccine candidate against dengue. By using the AQUA quantification strategy, we were able to develop, to validate and to transfer the method for the four chimeric virus serotypes. Then, problems met during development process, lead us to suggest check points to verify when using AQUA strategy. In a second part, we attempted to develop a quantitative label free analysis of 445 proteins to study the infection of the phytopathogen Dickeya dadantii, on a model plant. To ensure a simple and fast transfer of this multiplex, we purpose a new acquisition tool, independent from retention time. This tool was developed in a partnership with the R&D Sciex, Toronto and is called “Scout-SRM”
Cortejade, Aurélie. "Approches et outils pour l’évaluation de l’Exposome : du dosage de contaminants vers le screening non ciblé pour la caractérisation des expositions humaines environnementales". Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10219/document.
These research works highlight the development of analytical methods, based on mass spectrometry, to assess the Exposome according to different strategies. A selective multiresidue method for the analysis of plastic additives and their degradation products that may be released by plastic packaging in food and beverages and thus ingested by man was developed. This method consists of a Stir Bar Sorptive Extraction with bars covered by polydimethylsiloxane derivatives, followed by an analysis by liquid chromatography coupled to tandem mass spectrometry with a triple quadrupole instrument. To detect and quantify a wide range of contaminants in contact with man in daily routine, a screening method was developed by liquid chromatography coupled to high resolution mass spectrometry with a quadrupole-time-of-flight instrument from urinary matrix. The targeted screening method validated according to FDA guidelines allows the quantification of contaminants classified according to different families, in urine without sample preparation, at concentrations of the order of ng.mL-1. This method was applied to volunteers’ urine samples. The non-targeted screening method allows issuing numerous assumptions of compound identification after MS/MS fragmentation. The implementation of this tool to measure the Exposome associated with statistical studies, contribute greatly to the understanding of the causal relationships between diseases and environmental factors
Pereira, Hélène. "Développement de l'approche métabolomique par couplage chromatographie liquide / spectrométrie de masse : application à la nutrition". Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2010. http://tel.archives-ouvertes.fr/tel-00719399.
Jaffuel, Aurore. "Résolution de mélanges complexes d'oligosaccharides sulfatés par chromatographie 2D et spectrométrie de masse : application aux héparines thérapeutiques". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1150.
Delalande, François. "Application du couplage chromatographie liquide-spectrométrie de masse à l'étude de la biodisponibilité de peptides issus de produits laitiers et à la protéomique". Université Louis Pasteur (Strasbourg) (1971-2008), 2003. http://www.theses.fr/2003STR13068.
The LC-MS coupling has arisen as a method of choice for the quantification of molecules in a matrix, the determination of the primary sequences of peptides and proteins and for the establishment of post-traductional modifications. The progress realized both at the LC and at the MS level have revolutionized the biology allowing the identification of femtomolar amounts of proteins separated by 2-D electrophoresis in the context of proteomic studies and the detection of molecules of interest with always more sensibility for example in biological fluids (plasma, urine, cerebro-spinal liquid)My PhD work consisted in the choice and the perfecting of instrumental and analytical strategies by a deep optimisation of alls the parameters of the LC-MS and LC-MS-MS coupling. The first part relates to the experimental perfecting of the microLC-MS(-MS) technics for the characterization of peptidic compounds and the measurement of their biodisponibility. The second part focuses on the development, the optimisation and the use of the nanoLC-MS-MS for proteomic studies with a first proteomic study aimed at characterizing the interactions between rice and the rice yellow mottle virus. This work has permitted, thanks to Maldi-MS and LC-MS-MS technics, to show up the rice proteins that are recruited by the capsid proteins of the virus and to identify the proteins differentially expressed depending an the rice cultivars (resistant/sensitive). The second proteomic study concerns the characterization of expression markers linked to the abnormality "Mantled" by the oil palm needing de novo sequencing. To conclude, we have used the multiple potentialities of the microLC-MS and the nanoLC-MS-MS coupling to reply to diverse biological problems. These responses could have been obtained only thanks to the perfecting of particular methodologies
Favetta, Patrick. "Étude du métabolisme du propofol chez l'homme : intérêt des systèmes de couplage chromatographie-spectrométrie de masse". Lyon 1, 2001. http://www.theses.fr/2001LYO1T057.
Antonopoulos, Aristotelis. "Caractérisation par chromatographie en phase liquide et spectrométrie de masse d'oligosaccharides sulfatés : application à des hydrolysats de carraghénanes". Orléans, 2005. http://www.theses.fr/2005ORLE2032.
Jabot, Claire. "Développement de stratégies analytiques basées sur la LC-MS/MS pour la recherche de traces de pesticides et métabolites dans des matrices apicoles". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1216/document.
For several years, abnormally high mortalities have been observed in bees worldwide. Several factors may be responsible for these phenomena, including the use of pesti-cides. Among these, insecticides of the family of neonicotinoids and pyrethroids as well as some fungicides of the carboxamide family are implicated. The work presented is devoted to the development of analytical methods for the identification, detection and quantification of 13 pesticides and their metabolites in bees and hive products such as beebread and beeswax.Initially, an original dSPE method was developed for the extraction of targeted pesti-cides in beeswax. Combined with a liquid chromatographic analysis method coupled to triple quadrupole mass spectrometry (UPLC-MS/MS), it allows to reach limits of quantification never reached before in multi-families analysis on this complex matrix, between 1 and 40 ng.g-1.The application of this method to beeswaxes and the analysis of other beekeeping matrices provided by beekeepers (a total of 488 samples including 125 bees, 87 bees-waxes and 276 honeybees) showed a wide presence of these pesticides in french apiar-ies. Overall, beeswax is the matrix with the highest concentrations and beebread is the most contaminated matrix in terms of number of pesticides present.A second part of the work is devoted to the detection and identification of pesticide metabolites generated by in vitro and in vivo experiments. For this, an analytical strategy, based on the complementarity between time-of-flight and triple-quadrupole mass spectrometry, has been put in place. The first allows the identification of me-tabolites by combining the search for known metabolites and specific isotopic profiles (Cl, Br, S). The second allows their detection and quantification in bee samples.This dual approach has identified 9 pesticide metabolites and 5 markers of exposure. Metabolites and markers of exposure to boscalid (carboxamide), mainly derived from hydroxylation, dehalogenation and substitution reactions, have been synthesized. These were then detected and quantified in bee samples from symptomatic apiaries.These analytical developments and results make it possible, on the one hand, to make an inventory of the presence of pesticides of concern in french apiaries. On the other hand, they provide ecotoxicologists with data to better understand the behavior of pesticides in bees
Roux, Aurélie. "Analyse du métabolome urinaire humain par chromatographie liquide couplée à la spectrométrie de masse à haute résolution". Paris 6, 2011. http://www.theses.fr/2011PA066575.
Mendes, Siqueira Anna Luiza. "Apport de la spectrométrie de mobilité ionique couplée à la spectrométrie de masse pour la caractérisation de produits pétroliers formulés". Thesis, Normandie, 2018. http://www.theses.fr/2018NORMR044.
Nowadays, formulated petroleum products such as fuels and lubricants must respond toprecise technical requirements to ensure the best performance, reliability and longevity ofengines while limiting the emission of pollutants. This thesis work focused on the development of analytical methodologies for the identification of polymeric additives in diesel fuels and the characterization of polyalphaolefins. The additive analysis was performed by coupling of liquid chromatography, ion mobility spectrometry and mass spectrometry (LC-IMS-MS), the ionization was performed by electrospray (ESI). After adjusting the experimental parameters, all additives were identified in the diesel fuel without sample preparation. The coupling of liquid chromatography at the critical condition chromatography (LCCC) with mass spectrometry was also evaluated in order to improve the separation of additives from the diesel fuel matrix. The characterization of polyalphaolefins (PAO) was carried out by IMS-MS with ASAP (atmospheric solids analysis probe) or APPI (atmospheric pressure photoionization) sources. With ASAP, in addition to pyrolysis ions, intact species were detected for low PAO grades. In the case of high PAO grades, only pyrolytic fragments were detected, yet it was possible to identify the alphaolefins used to produce the PAOs. In APPI, the use of halogenated solvents and toluene, allowed to observe intact species for high PAO grades through the formation of halogenated adducts. With IMS-MS coupling polyalphaolefins were differentiated the by the study of drift times and full width at half maximum
Richert, Sophie. "De l'identification à la caractérisation de protéines : Développement de la spectrométrie de masse dans le cadre de l'approche protéomique". Université Louis Pasteur (Strasbourg) (1971-2008), 2003. https://publication-theses.unistra.fr/public/theses_doctorat/2003/RICHERT_Sophie_2003.pdf.
Venisse, Nicolas. "Procédure de recherche large ("screening") de xénobiotiques dans le sérum par chromatographie liquide - électrospray - spectrométrie de masse, appliquée à la toxicologie humaine". Bordeaux 2, 1999. http://www.theses.fr/1999BOR2P071.
Rochut, Nadège. "Analyse des somatotropines endogènes et recombinantes dans l'espèce bovine par chromatographie liquide couplée à la spectrométrie de masse en tandem : application au contrôle de leur utilisation illégale en élevage". Nantes, 2002. http://www.theses.fr/2002NANT2005.
Within the control of growth promoters illegally used in animal production, the french reference laboratory (LABERCA) has decided to direct one of its research topics towards the study of protein hormones : the somatropins. Mass spectrometry was used to determine exogenous character of recombinant somatotropins
Pennanec, Rodolphe. "Synthèses dirigées, purification et analyse de cyclodextrines anioniques par différentes méthodes séparatives et leurs couplages avec la spectrométrie de masse". Orléans, 2002. http://www.theses.fr/2002ORLE2048.
Antignac, Jean-Philippe. "Dosage et étude du métabolisme des corticostéroi͏̈des dans l'espèce bovine par chromatographie liquide couplée à la spectrométrie de masse en tandem : application au contrôle de leur utilisation illégale en élevage". Nantes, 2001. http://www.theses.fr/2001NANT2078.
Fifty years after the discovery of natural corticosteroid hormones and their anti-inflammatory properties, many synthetic derivatives of these molecules are today available. Most of them are widely used in human and veterinary medicines, in a legal but regulated scope. These compounds are also susceptible to be used as growth promoters, this utilisation remaining illegal in Europe. Consequently, an analytical method dedicated to the control of the utilisation of corticosteroids in cattle has been developed. In this analytical way, the present study permitted to propose a method based on LC-MS/MS measurement of corticosteroid residues in urine, tissue and hair samples
Simon, Romain. "La quantification ciblée de protéines et peptides par chromatographie liquide couplée à la spectrométrie de masse en tandem : développements analytiques et applications". Phd thesis, Université Claude Bernard - Lyon I, 2012. http://tel.archives-ouvertes.fr/tel-00875965.
Dubuis, Alexis. "Déformulation de matrices complexes : vers une méthodologie raisonnée adaptée aux matrices issues des procédés de valorisation de la biomasse". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1228/document.
The conversion of lignocellulosic biomass into biofuels and biosourced molecules produces complex thermosensitive liquid matrices which cover a wide range of polarity and molecular weight. Analytical tools developed in the literature only give a partial description of these oxygenated matrices. To understand the reactivity of these samples and optimize the development of conversion processes, a better characterization is required. The objective of this thesis is to demonstrate the interest of a relevant fractionation step prior to separation techniques to help the molecular characterization of biomass samples. The reverse engineering proposed for the sample is desired complete and chemically controlled (without loss or sample modification). Two fractionation pathways were investigated: (1) solubility fractionation with liquid-liquid extraction (LLE) and centrifugal partition chromatography (CPC) and (2) size fractionation with size exclusion chromatography (SEC). These techniques intend to be complementary to reversed-phase liquid chromatography hyphenated to ultraviolet-visible spectroscopy detection and high resolution mass spectrometry (RPLC-UV/HRMS). LLE, CPC and SEC methods were developed on model molecules to understand mechanisms involved and control the chemical selectivity. 2D contour plots were obtained, improving the resolving power and structuring chromatograms in comparison with RPLC-UV/HRMS. Then, SECxRPLC-UV/MS and CPCxRPLC-UV/MS hyphenations were applied to describe two complex samples from different substrates produced on experimental pilot units from two possible conversion pathways of lignocellulosic biomass (biochemical and thermochemical). The complementarity of separation modes allows to double the number of peaks detected, benefiting from the chemical organization of compounds. This constitute a support to identification also enhanced by multi-detection which provide additional structural information on compound detected, especially HRMS. Chemical organization in 2D contour plots were presented and discussed to propose the most adapted strategy to fully fractionate a sample based on the measurement of relevant descriptors. Finally, one of the fractionation approach developed in this thesis was used to isolate and structurally elucidate key molecules of a complex sample through MS fragmentation experiments and nuclear magnetic resonance spectroscopy (NMR)
Cecchini, Tiphaine. "Caractérisation de bactéries par analyses protéomiques en spectrométrie de masse". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1064.
Thanks to MALDI-TOF mass spectrometry, identification of isolated bacteria is now possible within a few minutes. But doctors also need to rapidly know the phenotype of resistance of the bacteria. Indeed, the patient mortality rate increases when the antibiotherapy is not appropriate. However, MALDI-TOF instruments are not able to analyze antibacterial resistance rapidly and comprehensively.Today, 6 to 24 hours are nedded for antibiotic susceptibility testing. When combining a liquid chromatography and a mass spectrometer with electrospray ionization (LC-MSMS), the detection of resistance biomarkers was possible within 1 to 2 hours. Using a Selected Reaction Monitoring (SRM) method, resistance mechanisms to beta-lactams, methicillin, glycopeptides and fluoroquinolones were detected in strains within 30 minutes. Tens of resistance determinants can be analyzed in a single multiplexed assay, with high specificity and sensitivity. Illustrated by the study of multifactorial resistance in Acinetobacter baumannii, the technology allows furthermore a quantitative analysis, which is of great value for some resistance mechanisms. Similarly, we identified virulent strains of enterohemorrhagic Escherichia coli by targeting toxins and serotype biomakers in the same assay. Mass spectrometry offered deeper bacterial characterization than conventional serotyping using polyclonal antibodies. However, despite all these favorable prospects, LC-MS/MS remains today far from reaching a routine use in microbiological hospital laboratories. Instruments are too expensive and the technology is too cumbersome for a daily in vitro diagnostic use. Waiting for a more suitable use, mass spectrometry could yet advantageously complement current molecular technologies. Today, the gold standard to study bacteria at molecular level is next generation sequencing. However, as demonstrated during this work, gene annotation remains imperfect. For tens of euros and few hours of analysis, peptides identified by mass spectrometry analysis of a bacteria might improve scaffold assembly and gene detection. Moreover, mass spectrometry gives an accurate protein quantitation and brings a new analytical dimension, potentially closer to the phenotype than molecular techniques. In conclusion, LC-MS/MS mass spectrometry could be an attractive complementary, or alternative technology in a near future, to conventional molecular biology techniques for deep characterization of bacteria
Bossant, Marie-Jeanne. "Étude structurale et dosage du paf-acéther et de ses dérivés par chromatographie en phase liquide ou en phase vapeur couplées à la spectrométrie de masse et au détecteur à capture d'électrons". Paris 11, 1988. http://www.theses.fr/1988PA114808.
Person, Marine de. "Analyse par chromatographie en phase liquide couplée à la spectrométrie de masse d'acides aminés et de petits peptides non dérivés dans des matrices agroalimentaires : développement et validation de méthodes". Orléans, 2005. http://www.theses.fr/2005ORLE2035.
Jacquet, Romain. "Cyclodextrines hydrophiles : caractérisation et étude de leurs propriétés énantiosélective et complexante : utilisation de la chromatographie en phase liquide et de la spectrométrie de masse". Phd thesis, Université d'Orléans, 2006. http://tel.archives-ouvertes.fr/tel-00185542.
Dans la première partie, une nouvelle CD méthylée faiblement substituée a été caractérisée par différentes techniques analytiques, permettant ainsi l'obtention d'informations complémentaires menant à une meilleure connaissance de la composition du mélange commercial. D'autre part, la séparation par chromatographie en phase liquide (CPL) des trois isomères de la sulfobutyléther-beta-CD monosubstituée a été optimisée sur carbone graphite poreux (PGC) en augmentant la température de la colonne.
La deuxième partie a porté sur l'évaluation du système chromatographique PGC / CDs méthylées pour la séparation chirale en CPL. Outre sa grande résistance physique et chimique, le PGC s'est révélé plus sélectif que les colonnes de silice greffée habituellement employées pour ce type de séparation et a nécessité une quantité moindre de CDs dans la phase mobile.
Enfin, dans la troisième partie, les complexes de différentes CDs méthylées avec des solutés test ont été étudiés par des expériences de partage liquide-liquide et par spectrométrie de masse à ionisation électrospray. La comparaison des résultats obtenus par ces deux méthodes a révélé que les signaux enregistrés en ESI-SM ne reflètent pas les équilibres existant en solution.
Maheux, Maxim. "Stratégies analytiques par chromatographie liquide avec détection en spectrométrie de masse afin d'évaluer l'activité de neuf enzymes du cytochrome P450". Thesis, Université Laval, 2012. http://www.theses.ulaval.ca/2012/28806/28806.pdf.
Al, Turihi Nour. "Caractérisation et quantification de la toxine et de l'anatoxine tétanique dans les vaccins par spectrométrie de masse". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1103.
The prophylactic drug, which has drastically reduced the impact and severity of tetanus on human populations, is the tetanus vaccine. Its active ingredient called tetanus toxoid results from the inactivation of tetanus toxin with formaldehyde. This chemical detoxification is a critical step, which determines the safety, antigenicity and immunogenicity of the vaccine. For a better understanding of this chemical process, at the molecular level, we first characterized tetanus toxoid by liquid chromatography coupled with high-resolution tandem mass spectrometry (LC-MS/MS) in order to fully identify and map all the modifications induced by formaldehyde on the three-dimensional structure of the vaccine protein. In a second step, for a better quality control of the industrial process of manufacturing tetanus toxoid, we developed in vitro expertise methods by LC-MS/MS to perform the relative and/or absolute quantification of tetanus toxin, tetanus toxoid, and to carry out the relative quantification of the toxin fragments chemically modified with formaldehyde. These characterization tools are complementary to existing quality control methods and currently contribute to better monitoring the reproducibility of tetanus vaccine batches
Mathe, Carole. "Etude de résines naturelles : caractérisation par CLHP et CPG couplées à divers modes de détection : UV/Visible, fluorimétrique et spectrométrie de masse". Avignon, 2003. http://www.theses.fr/2003AVIG0216.
This work concerns the study of two natural vegetable resins : olibanum and dragon's blood. Olibanum, is a oleo-gommo-resin only exuded by certain species of Boswellia (family of Burseraceae). The dragon's blood corresponds to a particular resin coloured in red. It is currently admitted, it is allowed that the true dragon's blood belongs to both species Daemonorops and Dracaena. Consequently, two samples were analyzed corresponding to Daemonorops draco (Indonesia) and Dracaena cinnabari (endemic species of Socotra's island, Yemen). Only the resin part (terpenic) of these substances was analyzed : the mono ones and sesquiterpenes (essential oils), the diterpenes and especially the triterpenes (ursane, oleanane, lupane and tirucallane skeletons). Various chromatographic techniques (LC/PDA/Fluorimetry, LC/SM and GC/MS) were employed to characterize these substances. The main goal of this work is to determine the specific chemical markers of these materials. Thus, seventeen molecules were isolated or hemisynthetized from commercial olibanum "Erytrean" type , as for example boswellic acids and their corresponding acetylated derivative, and a novel compound named lupeolic acid. Thermal degradation assays were also carried out ; studies of the released fume and the resinous residue obtained indicate the presence of products resulting from degradations : 24-noroléana-3,12-diene, 24-norursa-3,12-diene and 24-norlupa-3(20)29-diene. The thermal resistance of our standard compounds was also highlighted. Various geographical samples was also investigated to correlate the chemical composition and geographical origin. The species Boswellia carteri, Boswellia sacra and Boswellia frereana were differentiated. Moreover, our chromatographic methods also allowed the determination of fraud. Note that, the extrapolation of the results obtained on contemporary resins, allowed the characterization of olibanum in samples coming from the 18th century pharmacy or samples dating from ancient Egypt. Concerning the dragon's blood, both species considered were differentiated
Podevin, Christelle. "Détermination des alcools aliphatiques polyéthoxylés dans les eaux usées par couplage entre la chromatographie en phase liquide et la spectrométrie de masse". Lyon 1, 1998. http://www.theses.fr/1998LYO10173.
Bezy, Vincent. "Développement de méthodologies séparatives couplées à la spectrométrie de masse pour le dosage des nucléotides et nucléosides antiviraux du VIH". Orléans, 2005. http://www.theses.fr/2005ORLE2083.
Wiest, Laure. "Méthodologies analytiques basées sur la chromatographie liquide couplée à la spectrométrie de masse pour la quantification multi-familles de tensioactifs dans les rivières". Electronic Thesis or Diss., Lyon, 2021. http://www.theses.fr/2021LYSE1138.
The number of chemicals on the market is increasing every year. Moreover, they are more and more complex and the formulations contain mixtures that are finally disseminated in various compartments of the environment. Among these micropollutants, surfactants present some particularities. First, surfactants are complex mixtures of homologues and isomers whose composition depends on the raw materials and the synthesis processes used. Secondly, some, such as linear alkylbenzene sulfonates (LAS) and triethanolamine esterquats (TEAQ), are used in very large quantities, which may induce "pseudo-persistence" in the receiving environments. Finally, the fields of application of surfactants are extremely varied, ranging from domestic to industrial, agricultural and hospital, which suggests a large number of sources of transfer to the environment. The data concerning their occurrence are very heterogeneous according to the families, and some types of surfactants have never been looked for in rivers until now. The objective of this thesis was therefore to develop sensitive and reliable analytical methodologies to fill this knowledge gap concerning the occurrence of surfactants in the environment. In order to obtain sufficient sensitivity, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was first optimized. Contamination of instrumental blanks, in particular by anionic surfactants, at concentrations between 0.1 µg/L and 3 µg/L was observed. As the limits of quantification (LOQ) were still too high compared to the PNEC, a pre-concentration step by solid phase extraction was developed for the analysis in river water. For sediment analysis, an ultrasound-assisted extraction was optimized and validated. With LOQs between 0.015 and 0.485 µg/L for water and between 6.4 and 158 µg/kg for sediment, the analytical performances obtained are compatible with trace analysis. The application of these methodologies to river waters and sediments sampled in France showed a high occurrence of surfactants in these media. In particular, LAS have both high quantification frequencies and high mean concentration to PNEC ratios, and therefore represent a significant risk to ecosystems
Ghezal, Salma. "Etude métabolomique par LC-MS/MS chez Plasmodium Falciparum, parasite responsable du Paludisme". Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20179.
The most severe form of malaria is caused by the single-celled parasite P. falciparum. During the intra-erythrocytic stage of its development, P. falciparum implements several metabolic functions necessary for its development in the erythrocyte, its multiplication and finally to its spread to other erythrocytes. Understand and elucidate the structures and the dynamics of the parasite's metabolic network is useful to discover new metabolic pathways and key steps that may play an important role in the development of the parasite. They also help determine the mechanism of action of antimalarial agents and better understand the resistances associated with available treatments. For this purpose, a targeted metabolomics approach, using liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used. This approach consists of an absolute quantitation of metabolites involved in the biosynthesis of membrane phospholipids of the parasite but also other metabolites that reflect its metabolic status. We initially determined the distributions and the absolute amounts of metabolites in infected erythrocytes in comparison with healthy erythrocytes. We also highlighted the disruption caused by this infection on the metabolism of the human erythrocyte and the various interactions between the parasite and its host cell as well as the extracellular medium. The phospholipids metabolism of Plasmodium is complex because it has several synthetic pathways operating from separate initial precursor and leading to the synthesis of a single end product. With the aim to study the relative contribution of these different metabolics pathways in the biosynthesis of the most important phospholipids in P. falciparum (PC and PE), we have developed an approach that involves incubation of infected erythrocytes in the presence of labeled precursors
Dauchy, Xavier. "Spéciation des butylétains dans les sédiments marins par couplage chromatographie en phase liquide - plasma à couplage inductif/spectrométrie de masse (HPLC-ICP-MS)". Pau, 1993. http://www.theses.fr/1993PAUU3003.
Goulitquer, Sophie. "Identification et dosage de dérivés oxydés d'acides gras polyinsaturés dans les milieux biologiques par une approche métabolomique ciblée". Brest, 2008. http://www.theses.fr/2008BRES3075.
Oxylipids/oxylipins, oxidized derivatives of polyunsaturated fatty acids, play a major role in lipid signalization, during biotic or abiotic stress, in both mammals ans in higher plants. We established specific methods for quantifying oxylipids in biological samples of human or phycologic (algae) origin. These methods are based on mass spectrometry coupled with gas or liquid chromatography (GC/MS/NCI and LC/MS). Thus, we have : -established a quantification method of EETs from human blood by GC/MS/NCI. These arachidonic acid (AA) metabolites by the action of cytochromes P450, have vasorelaxation properties. -highlighted the specific production of 20-HETE, an AA metabolite, by the CYP4F3B in a human hepatoma cell line, HepaRG. -studied the formation of docosahexaenoic acid (DHA) 19,20-epoxide enantiomers after incubation of recombinant human cytochromes P450 with [14C]-DHA and their separation on a chiral column. -identified an oxylipin signature of the response of the brown marine alga Laminaria digitata during abiotic stress, induced by copper, revealing enzymatic and chemical synthesis pathways. The presence of a new compound, the 18-hydroxy, 17-oxo-eicosatetraenoic acid has been described. -highlighted the polyinsaturated aldehyde emission in response to stress in this alga. These compounds are involved in distance signaling and inter-plant communication leading to a priming of defenses during a biotic stress mimicked by oligoguluronates. These results could allow a better comprehension of the oxylipid role in man as algae
Poyer, Salomé. "Développement de méthodes d'analyse par spectrométrie de masse à mobilité ionique pour l'identification des analogues de saxitoxine". Rouen, 2015. http://www.theses.fr/2015ROUES053.
This thesis work focused on the separation and identification of saxitoxin analogues, natural neurotoxic compounds. Modern separation techniques such as hydrophilic interaction liquid chromatography (HILIC) and ion mobility spectrometry (IMS) coupled to mass spectrometry (MS) were developed for the analysis of saxitoxins. HILIC-MS and IMS-MS coupling were developed, showing a complementary for separation of the various saxitoxin analogues. HILIC-IMS-MS coupling was then optimized and allowed the fast separation of the toxin analogues. The HILIC-IMS-MS coupling was also repeatable when complex mixtures were injected, although it was less sensitive than with the coupling of HILIC with a triple quadrupole instrument operated in targeted mode. IMS application to saxitoxins also permitted to determinate the collision cross section values of each analogue. The calculation of theoretical structures permitted the determination of theoretical collision cross sections that were correlated to experimental values and allowed the access of gaseous phase conformation. Saxitoxin analogues characterization was carried out by tandem mass spectrometry of [M+H]+, [M+Li]+, [M+Na]+, [M+K]+ and [M−H]− species. The different product ions gave information about stability of chemical functions depending on the different species studied
Werner, Erwan. "Analyse du métabolome par chromatographie liquide couplée à la spectrométrie de masse : application à la recherche de biomarqueurs indirects d’induction enzymatique". Thesis, Paris 11, 2011. http://www.theses.fr/2011PA114817/document.
This work is the result of a research partnership between the CEA and Les laboratories Servier. It deals with the characterization of biomarkers of metabolic enzyme induction in rat biofluids using MSbased metabolomics. The first part of this work included methodological developments regarding theacquisition and the processing of metabolic fingerprints. A tool based on autocorrelation matrices wasthen implemented to reduce the redundancy of data generated with mass spectrometry and subsequently accelerate the isolation of discriminating variables. The next step consisted in the evaluation of the combined use of Kendrick mass defects and methylene selectivity as an alternative visualization tool for large data set, which would rely on compound chemical structures. Finally, the last part of the work was dedicated to the identification of discriminating signals raised up by ametabolomic global approach from rat biofluids collected before and after an induction assay
Herviou, Pauline. "Personnalisation des posologies en oncologie selon le profil pharmacocinétique et pharmacogénétique, avec comme modèle l'irinotécan et le bevacizumab". Thesis, Clermont-Ferrand 1, 2016. http://www.theses.fr/2016CLF1MM04.
Usually, the dosage of anticancer is normalized with used to the patient's body surface area(sometimes its weight). However, this adaptation does not take into account the interindividualpharmacological variability in the pharmacokinetics of the drug. Factors modulating thispharmacokinetics are numerous, including interindividual capacities of metabolism and elimination.At the same dosage, the systemic exposure of the patient can thus be changed, and cause a risk ofoverdosing for some patients, with the development of toxicities, or under dosing for others, withlimiting the therapeutic efficacy. Alternatives to the use of the body surface area have been proposedin order to more take account of inter-individual variability of patients, such as therapeutic drugmonitoring or pharmacogenetics. Genetic polymorphisms of enzymes involved in the metabolism ortransport of a cytotoxic, can change and modify their activity, and impact on drug’s metabolism. Thedevelopment of knowledge in these areas could allow the establishment of new methods to dosage’sadjustment.This PhD project focuses on individualizing dosage of anticancer focusing in both cytotoxicchemotherapies with the model of irinotecan, as targeted therapies, distinguishing in this same classtyrosine kinase inhibitors and monoclonal antibodies (bevacizumab model). To optimize thetherapeutic index of these therapies, the dose adjustment was according to pharmacogenetics profile,but also according to the pharmacokinetics profile.A clinical study was developed to studying, in terms of toxicity and efficacy, the interest ofadapting dosage of irinotecan in combination of chemotherapy to traitement of metastatic colorectalcancer (FOLFIRI +/- bevacizumab or cetuximab), based on a genetic polymorphism of UGT1A1, anenzyme involved in its metabolism. Results of the interim study of this phase II trial, conducted in 16patients, are in favor of study continuation with 12.5% grade 4 hematological toxicities, and objectiveresponse rate of 58.3%. The secondary objective was to study the pharmacokinetics of irinotecan andits metabolites during one cycle. These assays were performed by liquid chromatography-massspectrometry. This technique, widely used for quantification of drug in plasma was developed andvalidated according to standards. The dosage of bevacizumab, a monoclonal antibody used tocolorectal cancer treatment (associated to FOLFIRI) was also developed by this technique, withspecific peptide identification, and optimization of sample preparation and analytical technique.In parallel, the implementation of the determination of tyrosine kinase inhibitors by massspectrometry and its validation were part of this PhD project, and allow its use in hospital routine intherapeutic drug monitoring
Larose, Jessica. "Analyse des isomères de F2-isoprostanes par chromatographie liquide couplée à la spectrométrie de masse dans la circulation maternelle en fin de grossesse". Master's thesis, Université Laval, 2013. http://hdl.handle.net/20.500.11794/25559.
Un stress oxydatif survient lorsqu’il y a surproduction de dérivés actifs de l’oxygène par rapport aux défenses antioxydantes. Ce déséquilibre est associé, entre autres, à la prééclampsie, une pathologie de la grossesse. Les F2-isoprostanes regroupent soixante-quatre isomères issus de la peroxydation de l’acide arachidonique. Ceux-ci sont reconnus comme étant les biomarqueurs les plus fiables du stress oxydatif in vivo. Une méthode d’analyse par chromatographie liquide couplée à la spectrométrie de masse en tandem pour le dosage de sept isomères de F2-isoprostanes dans des échantillons de plasma, de sang et de membranes érythrocytaires a été mise au point et validée. Les F2-isoprostanes dans le plasma ont été corrélés positivement avec plusieurs acides gras trans plasmatiques au troisième trimestre de la grossesse. Contre toute attente, les F2-isoprostanes du plasma, du sang et des membranes érythrocytaires sont moins abondants en prééclampsie par rapport aux contrôles en fin de grossesse.
An oxidative stress is defined as an imbalance between the production of reactive oxygen species and antioxidant defenses of the organism. This imbalance has been associated with preeclampsia, a pathology of the mid-to-late pregnancy. Peroxidation of arachidonic acid generates sixty-four isomers of F2-isoprostanes. The latter are recognized as the most reliable biomarkers of oxidative stress in vivo. A method using liquid chromatography tandem mass spectrometry (HPLC-MS/MS) for the determination of seven isomers of F2-isoprostanes in plasma samples, whole blood and erythrocyte membranes has been developed and validated. The F2-isoprostanes correlated positively with several trans fatty acids in plasma at end of the pregnancy. Unexpectedly, F2-isoprostanes were less abundant in preeclampsia than in control pregnancies at the third trimester.
Roy, Sandrine. "Analyse des bio-marqueurs de la maladie de Fabry par techniques séparatives couplées et spectrométrie de masse". Paris 11, 2005. http://www.theses.fr/2005PA114841.
Fabry disease in an X-linked inborn error of neutral glycosphingolipids (GSLs) metabolism, caused by a deficiency of the lysomal α-galactosidase A, wich results in high levels of globotriaosylceramide (Gb3) and galabiosylceramide (Ga2). Different techniques are developed to analyse lipid classes and molecular species in each lipid class. First, we optimised the separation of four major neutral GSLs. An HPLC separation combined with evaporative light-scattering detection allowed the detection of urinary globotriaosylceramide in urinary sediments of patients. Second, we analysed the different molecular species of Gb3 and Ga2 in urinary sediments with tandem mass spectrometry (MALDI Q-TOF and HPLC APPI MS-MS). About twenty molecular species are identified for Gaé and Gb3. Third, these lipids were analysed directly on the surface of tissue sections. MALDI-TOF ond cluster-TOF-SIMS imaging approaches were used to obtain the localization of GSLs on skin and kidney sections of patients affected by the Fabry disease
Gervais, Gaël. "Rôle des paramètres opératoires sur la fiabilité d’une analyse multi-résidus de micropolluants dans l’eau : extraction sur phase solide, séparation par chromatographie liquide à très haute pression et détection par spectrométrie de masse en tandem". Rennes 1, 2010. http://www.theses.fr/2010REN1S057.
The occurrence of micropollutants is a major aspect in water quality assessment. For the last few years, analytical methods combining solid-phase extraction, liquid chromatography and tandem mass spectrometry has become the main technique for the analysis of a broad range of micropollutants. On the basis of some pesticides and endocrine disruptor compounds in water analysis, impacts of the parameters: extraction, separation, detection and data processing, on the analysis reliability (repeatability, accuracy, stability, reproducibility…) have been studied. Each step of the analytical method has been optimized and the parameters, affecting substance signals have been discussed. A global reflection upon the cause of signal variations and the possible answers to apply has been conducted. Proposed answers were validated by real matrix analysis and inter-laboratory studies. This work presents the tools and the key-points to ensure the results obtained by liquid chromatography/tandem mass spectrometry analysis
Oursel, Delphine. "Influence de l’expression de l’ATP synthétase sur la composition lipidique des membranes bactériennes chez Escherichia coli : Identification et quantification relative des phospholipides et acides gras constitutifs par spectrométrie de masse". Rouen, 2008. http://www.theses.fr/2008ROUES062.
For years, investigations of growing interest deal with the potential lipids preference of membrane proteins and/or enzymes, these affinity phenomenons are supposed to induce the formation of lipids domains also called lipids rafts inside biological membranes. This thesis focused on the ability of ATP-synthetase, a membrane protein, to induce lipids domains in a cellular model, the E. Coli bacteria. Hence, 4 bacterial strains were studied to evaluate the influence of protein expression, a wild type and three genetically modified strains with variable enzyme rates. Analytical methodologies were developed for this purpose and involved various MS techniques. Then, LC-MS and GC-MS techniques were used for the analysis of phospholipids and constitutive fatty acids, respectively. This approach provided the identification of all the phospholipids. Moreover, the structure of the constitutive fatty acids and their location on the glycerol backbone were determined
Dadi, Hala. "Analyse par spectrométrie de masse des tubulines et de l'hormone de croissance". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS582.
The tubulins are proteins involved in cellular processes that are essential for cell life. The tubulins are polymodified at their C-terminal extremities. Different techniques have been used to characterize the polymodifications of tubulins. However, some challenges remain in the fine identification of some structures. In fact, mass spectrometry ion mobility can separate ions of the same m/z ratio depending on their conformations. In the first part of this thesis, an ion mobility mass spectrometry analysis allowed the separation of two synthetic peptides that mimic the structure of C-terminal peptides of biglycylated α-tubulins. In order to extrapolate this type of experiment to the C-terminal peptides purified from biological tubulins, we employed an analytical process to analyze these peptides from purified brain tubulins. Growth hormone (GH) is an anabolic hormone and a doping agent used by athletes. The availability of rhGH in the black-market has continuously increased because of doping in sports. The natural and the biosynthetic hGH have identical peptidic sequences. So far, the valid hGH anti-doping tests by the world antidoping agency are based on immunological recognition. However, Immunoassays have their own limitations. Therefore, the next generation analysis of GH has to be more specific and accurate. In the second part of this thesis, mass spectrometry coupled to reversed phase chromatography was used to find chemical differences between the pituitary hGH and the rhGH. The pituitary extracted hGH is glycosylated whereas the biotech product is sugar free. The present work represents an opening towards a novel methodology for a novel hGH anti-doping test
Valette, Gilles. "Biotransformation et détermination du caractère lipophile de pronucléotides à visée antivirale : étude par chromatographie liquide hautes performances (C.L.H.P.) et couplage C.L.H.P./spectrométrie de masse". Montpellier 2, 1998. http://www.theses.fr/1998MON20027.
Chirita, Raluca-Ioana. "Développement de nouvelles méthodes séparatives compatibles avec une détection par spectrométrie de masse et par électrochimie pour l'analyse de traces de catécholamines et molécules apparentées". Thesis, Orléans, 2009. http://www.theses.fr/2009ORLE2043/document.
As neurotransmitters, catecholamines play an important role in the control and regulation of numerous brain functions. They are also believed to be implicated in different neurodegenerative disorders. First an ion pairing chromatography method using nonafluoropentanoic acid as volatile ion paring agent was developed on the new generation of C18 columns (monolith and fused core). This method is compatible with MS detection in positive ionization mode. Secondly an HILIC method was optimized using different commercially available HILIC supports, they can be classified as follows: neutral (diol, amide, and cyano bounded), positively charged (amino, triazole bounded), negatively charged (bare silica as wholly porous particles or fused core particles columns) and zwitterionic (sulfobetaine bounded). Our studies lead us to a better understanding of the HILIC retention mechanism and also to the selection of the most appropriated column for catecholamine analysis. Only the HILIC system was compatible with both positive and negative ionization modes. The two chromatographic systems were then compared in terms of resolution, efficiency, detection and quantification limits (LOD/LOQ), calibration linearity and repeatability. The LODs obtained were in the range of 1-100 ng.mL-1. A simple pre-concentration method using Oasis HLB and PGC solid phase extraction cartridges has been optimized in order to enhance the LODs. Finally the optimized SPE-LC-MS/MS method has been applied to the identification of these compounds present in brain extracts
Hazotte, Aurélie. "La micro chromatographie liquide à haute température pour l'analyse rapide et hautement discriminante des lipides d'intérêt biologique". Paris 11, 2007. http://www.theses.fr/2007PA114818.
The structural complexity of lipids and their lack of chromophores make their separation and their detection difficult in liquid chromatography. The aim of this thesis is the development of an analysis technique which is at the same time discriminating, sensitive, fast and efficient. The micro high-temperature liquid chromatography (µHTLC) coupled with an evaporative light scattering detector (ELSD) adapted to micro flow rates, was implemented on porous graphitized carbon (PGC). A kinetic study has highlighted the real enhancement of efficiency obtained in µHTLC at elevated temperatures and flow rates. This technique allows to strongly decrease analysis times and to improve peaks shape. A scale of eluotropic strength was established on the basis of methylene selectivity on PGC: increasing emperatures modify the eluotropic strength of organic solvents which allows the use of alcohols solvents, less toxic that those classically used in lipids analysis. An application was realized on complex mixtures of lipids to illustrate the potential of the µHTLC and PGC in separation of these molecular species. In addition, µHTLC was coupled with DEDL, mass spectrometer and aerosol charged detector (CAD), in order to position this latter in term of performance compared to the two others detectors and to study effects of µHTLC on detectors response. Finally, concerning the modulation of the selectivity by temperature, a study was realized based on analysis of triacylglycerols in isotherm and temperature gradient mode
Sommerer, Nicolas. "Isolement et identification de petits peptides présents dans l'extrait hydrosoluble sapide de fromage de chèvre et de jambon cuit par chromatographie en phase liquide et spectrométrie de masse". Dijon, 1997. http://www.theses.fr/1997DIJOS070.
Tachon, Romain. "Apport de la chromatographie en phase liquide couplée à la spectrométrie de masse pour l'analyse de traces d'explosifs : optimisation des conditions d'extraction et de purification pour le traitement d'échantillons récupérés sur une scène d'attentat". Paris 6, 2008. http://www.theses.fr/2008PA066669.
Chaimbault, Patrick. "Analyse d'Acides Aminés non dérivés par Chromatographie en Phase Liquide avec le Détecteur Evaporatif à Diffusion de la Lumière et Couplage avec la Spectrométrie de Masse". Phd thesis, Université d'Orléans, 2000. http://tel.archives-ouvertes.fr/tel-00152167.
Pour éviter l'étape de dérivation, la Chromatographie en Phase Liquide (CPL) est ici associée au Détecteur Evaporatif à Diffusion de la Lumière (DEDL) ou couplée à la Spectrométrie de Masse (SM). Ces deux modes de détection sont quasi universels mais requièrent la mise au point de phases mobiles volatiles.
Parmi les systèmes CPL testés pour l'analyse directe des acides aminés, le carbone graphitique poreux a été retenu et évalué comme phase stationnaire. Une phase mobile aqueuse saline, volatile, composée d'acétate d'ammonium, ajustée à pH=9,3, permet notamment la séparation d'acides aminés soufrés analogues de la taurine et la séparation partielle d'acides aminés protéiques. En revanche, la séparation totale des 20 acides aminés protéiques est obtenue avec une phase mobile contenant un acide carboxylique perfluoré (acide nonafluoropentanoique) comme agent d'appariement d'ions volatil, en gradient d'élution, à 10°C, en une quarantaine de minutes.
Les systèmes CPL mis au point avec le DEDL sont directement compatibles avec la SM. En utilisant la spécificité de détection de la SM et la SM tandem, l'analyse des acides aminés protéiques est possible en 20 minutes. Si le DEDL ne permet pas de descendre à des concentrations détectées inférieures au mg/l, la SM tandem autorise des limites de détection avoisinant quelques dizaines de µg/l seulement. La CPL-SM tandem a permis le dosage direct d'acides aminés soufrés dans des invertébrés marins.
Caumette, Guilhem. "Analyse de spéciation des métaux dans les produits lourds du pétrole par couplage LC-ICP MS (Chromatographie liquide – Spectromètre de masse à plasma induit)". Pau, 2009. http://www.theses.fr/2009PAUU3029.
The use of heavy petroleum, increasingly popular because of the shortage of energy supplies, is hampered by the presence of heavy metals, such as nickel and vanadium, which negatively affect refining processes. The objective of the thesis was to develop novel analytical methods able to study the metal distribution in petroleum, its fractions and related products. The principal developments include: (i) a high-throughput sensitive method for the analysis of organic matrices based on flow-injection total consumption micronebulisation ICP MS; (ii) a coupling of gel-permeation LC with ICP MS; and (iii) a coupling of normal phase LC – ICP MS allowing the 2D gel-permeation – normal phase characterization of the metal distribution by ICP MS. The methods developed were applied to the analysis of a number of crude oils and their fractions