Dissertations / Theses on the topic 'Spectrométrie de masse SALDI'
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Moustiez, Paul. "Fabrication de nano-aiguilles en silicium en vue d'une détection intracellulaire de biomarqueurs de maladies neurodégénératives." Electronic Thesis or Diss., Université de Lille (2022-....), 2023. https://pepite-depot.univ-lille.fr/ToutIDP/EDENGSYS/2023/2023ULILN054.pdf.
Neurodegenerative diseases are chronic progressive diseases affecting the central nervous system. While these diseases have multifactorial origins, their prevalence increases with age. Due to the progressive aging of the population and the absence of treatment, they are becoming a crucial public health issue. For example, Alzheimer's disease will affect 1 person out of 85 worldwide by 2050. In this context, researchers are studying various options to gain a better understanding of this disease and its pathophysiological mechanisms. They now know that hyperphosphorylation of the Tau protein and the production of toxic forms of beta-amyloid peptides that aggregate into senile plaques are the main causes. The origin of these dysfunctions is still poorly understood but could be elucidated by studying intracellular biochemical mechanisms. In this context, we have conceived an in vitro device based on the use of silicon nanoneedles with the ability to probe the cytoplasm of neuronal cells to detect Alzheimer's biomarkers and monitor their evolution. Our work was based on the development of this sensor, which was divided into 3 points. The first was the fabrication of nanoneedles through the development of cost-effective techniques such as nanosphere lithography followed by wet or dry etching methods. The second point was the optimization of these needles for the bimodal identification of molecules by mass spectrometry (SALDI-MS) and surface-enhanced Raman spectroscopy (SERS). The third point focused on the study of the interaction between our needles and neurons with the aim of capturing biomarkers and preserving cellular integrity. Nanosphere lithography was successfully developed, and the needles were manufactured using two methods: metal assisted chemical etching (MACE) and dry etching by continuous plasma etching. Rhodamine 6G, standard peptides, and beta-amyloid peptides could be detected by SALDI-MS and SERS on our needle arrays. Finally, we observed the biocompatibility of our needles with the cellular environment and characterized their interaction
Suarez, Stéphanie. "Microbiologie clinique et spectrométrie de masse." Phd thesis, Université René Descartes - Paris V, 2013. http://tel.archives-ouvertes.fr/tel-00920410.
Jankowski, Krzysztof. "Spectrométrie de masse des acides nucléiques." Paris 11, 1985. http://www.theses.fr/1985PA112257.
The nucleic acids and the oligonucleotides have been studied by using different mass spectrometric techniques. Through the revue and three chapters of particular interest (fragmentation mechanisms under normal and slowed down pyrolysis conditions, some biochemical applications and finally the oligonucleotide sequence studies using FAB ionization) we present these studies
Gilles, Isabelle. "Spectrométrie de masse et réactivité chimique." Montpellier 2, 1995. http://www.theses.fr/1995MON20080.
Jeanne, dit Fouque Kevin. "Différenciation de topoisomères peptidiques par spectrométrie de masse à mobilité ionique et spectrométrie de masse en tandem." Rouen, 2016. http://www.theses.fr/2016ROUES020.
Lasso peptides are ribosomally synthesized and post-translationnally modified peptides produced by bacteria, sharing a mechanically interlocked topology that is essential for their biological activity. This PhD work focused on the structural characterization of lasso peptides and differentiation between their branched-cyclic topoisomers using ion mobility – mass spectrometry (IM-MS) and tandem mass spectrometry (MS/MS). IM-MS studies led to the development of a method based on the use of a supercharging reagent, highlighting an additional charge state of multiply protonated species, for which the lasso and branched-cyclic topologies were clearly differentiated and separated in mixture. To assess the developed method, this strategy was also applied to other types of constrained (macrocyclic, disulfide bonds) and unconstrained (linear) structures. IRMPD spectroscopy studies allowed to characterize the changes in the hydrogen bond network, associated with the unfolding of the gas phase conformation, as a function of the charge state of multiply protonated species. The spectroscopic data could thus be correlated with the ion mobility data. IM-MS provides an overview of the conformation through a collision cross section measure (CCS), while IRMPD spectroscopy allows to probe intramolecular interactions through the hydrogen bonds. The structural characterization of lasso and branched-cyclic peptides was also carried out using MS/MS of triply protonated species. These experiments enabled us to establish general rules of fragmentation evidencing lasso topologies in collision induced dissociation (CID) and electron transfer dissociation (ETD)
Domalain, Virginie. "Différenciation de stéréoisomères par couplage, spectrométrie de masse et spectrométrie de mobilité ionique." Rouen, 2014. http://www.theses.fr/2014ROUES023.
This PhD work deals with analysis of stereoisomers, which present very close collision cross section difference (DeltaCCS ≤ Å2), by the coupling of ion mobility spectrometry and mass spectrometry (IM-MS). A study of diastereoisomers M which are functionalized entities found in a lot of natural products, rise to an efficient strategy based on cationisation (with alkali cations X and transition metals (X)II) and formation of multimers [3M+X]+ and [3M+(X)II-H]+ allowing the differentiation and the separation of stereoisomers, particularly enantiomers of amino acids and diastereomers with a major biological interest. It has been highlighted that the cationisation allows a significant increase of the stereoisomers differenciation. Then, we have shown that the nature of asymmetric center substituents plays an important role on the ion mobility separation
Tirsoaga, Alina. "Analyse structurale d'endotoxines bactériennes par spectrométrie de masse." Paris 11, 2007. http://www.theses.fr/2007PA112002.
Endotoxins are lipopolysaccharides (LPS) made up of a lipid - (called lipid A) and a sugar - chain, both characteristic of each bacterial species. We developed methods of structure analysis and a purification method representing an important improvement for studies of structure/activity relationships. The first one is a micro analytical method that can be applied to milligram quantities of bacteria. With it, one can obtain spectra of the lipid A in one day, instead of a week as for previous techniques. The second one leads to the determination of the structure and the positions of the fatty acids with a little amount of lipid A. This technology was applied to Citrobacter, an Enterobacterium causing nosocomial diseases. A LPS purification method gave highly purified samples suitable for biological tests. This method will give preparation having identical activities in different laboratories. We also have established the existence of new constituents on the lipid A of B. Bronchiseptica, from which the whooping cough originated. The presence of a glucosamine on the phosphate group(s) was demonstrated and its effect on the biological activities will be of high impact particularly on the activity of anti-bacterial peptides, as glucosamines neutralise the lipid A structure responsible for the endotoxic activities of LPS
Causse, Jean Etienne. "Spectrométrie de masse de quatre séries de phosphonates." Montpellier 2, 1991. http://www.theses.fr/1991MON20231.
Vanbellingen, Quentin. "Imagerie de substances naturelles par spectrométrie de masse." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS172/document.
This thesis was devoted to the improvement of mass spectrometry imaging methods, and to their use for in situ analysis of natural substances. The first part of this thesis has been dedicated to the development of a new acquisition mode in TOF-SIMS imaging able to acquire images with a high spatial resolution of 400 nm while keeping a good mass resolution. For that, a delayed extraction of the secondary ions has been characterized and optimized. Then, a second part has been dedicated to the study of heartwood production in a tropical species named Dicorynia guianensis. This species is one of the most exploited in French Guiana for its heartwood which exhibits a good durability. Metabolic changes are shown by sub-micrometric resolution ion images recorded in and around the transition zone, where the heartwood formation occurs. Then, TOF-SIMS and MALDI-TOF have both been used to analyse the surface of a bacterial competition. Species have been isolated from a Japanese conifer (Cephalotaxus harringtonia), from which the stains are an endophitic fungi (Paraconiothyrium variabile) and a pathogenic bacteria of the conifer (Bacillus subtilis). The results have shown that the fungus is able to hydrolyze surfactines produced by the bacteria during the competition. Furthermore, both the MALDI-TOF and the TOF-SIMS mass spectrometry imaging are methods of choice to study in vitro models of what could happen in vivo
Collard-Simard, Gabriel. "Caractérisation du récepteur de l'insuline par spectrométrie de masse." Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25309/25309.pdf.
Dufresne-Martin, Geneviève. "Développement d'outils proteomiques basés sur la spectrométrie de masse." Mémoire, Université de Sherbrooke, 2004. http://savoirs.usherbrooke.ca/handle/11143/3365.
Bouclon, Julien. "Spectrométrie de masse FT-ICR bidimensionnelle, développements et applications." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEE002/document.
Mass spectrometry provides two kinds of information: the molecular mass of molecules present in a mixture, obtained all at once (MS), and structure through isolation and fragmentation, obtained one by one (MS/MS). Two-dimensional FT-ICR MS allows simultaneous parallel acquisition of structural information without isolation, regardless of the number of molecules. Nevertheless, the low resolution in the indirect dimension, which could be improved by increasing the acquisition time, seemed to limit this method to a simple curiosity. The first objective is to implement non-uniform-sampling (NUS) in 2D FT-ICR MS. This method consist in the random acquisition of the same number of points in the indirect dimension as in uniform acquisition, but over a wider t1max range. Processing algorithms then reconstruct skipped points, and the result is an increase of signal resolution without wasting analysis time. The first step is to create an algorithm that can generate random sampling with a uniform distribution for an optimal coverage of the t1max range. Processing algorithms may have trouble to reconstruct small peaks when the number of skipped points increases. The second step is to choose the under-sampling ratio for the best compromise between the gain in resolution and the signal-to-noise ratio. The third and last step is to obtain MS/MS spectra with corrects isotopic patterns for fragments produced from heavy isotopes. The second objective is to improve the understanding of ion motions in ICR cells depending on the RF pulses by using Lorentz equations. The first goal is to determine the equations governing precursors motions until their detection. Then the fragmentation will be introduced and analytical solutions describing fragments motions will be established. The last step is to simulate the trajectories of precursors throughout the entire pulse sequence as well as the behavior of fragments clouds, from their formation to detection
Bou, Raad Roland. "Caractérisation protéomique de la mycomembrane de Corynebacterium glutamicum." Paris 11, 2010. http://www.theses.fr/2010PA112165.
Corynebacterinearis a specific sub-order of Gram-positive bacteria including Mycobacterium tuberculosis and Corynebacterium glutamicum. The utrastructure of their cell envelope is very atypical. The cell wall consists of a peptidoglycan layer covalently linked to arabinogalactan, a polymer of arabinose and galactose, characteristic of this group of bacteria. Arabinogalactan is esterified by mycolic acids, fatty acids found only in Corynebacterineae, and forming an outer membrane the mycomembrane. The presence of this mycomembrane raises the question of the equipment required for protien import of mutrints, signal transduction and secreton of proteins to the cell surface and in the external environnement. It is in this context that the work of my thesis has aimed to identify the proteins of the mycomembrane of C. Glutamicum by a proteomical approach. To isolate the mycomembrane of C. Glutamicum we adopted two biosynthesis of the arabinogalacian (ΔaftB). Indeed, we showed that this mutant spontaneously released outer membrane fragment in the culture medium. In parallel, we developed a method of separation of membranes on sucrose gradient on the wild strain 13032. The identification of proteins from these two approaches was made by MALDI-TOP MS and ESI-nanol. C. MS / MS. We succeeded to indentify 66 proteins that we propose to be located in tne mycomembrane. These proteinswere classified into five categories: 1) porins, 2) lycikiyktrabsferasesn 3) lipoproteins, 4) PS2 C-terminal like proteins, 5) hypothetical proteins. This list of proteins, far from exhaustive, represents the first reference describing experimentally mycomembrane protein composition in C. Glutamicu. In the last part of my thesis, we were interested in mycoloytransferases, a family of enzymes involved in the biosynthesis of the mycomembrane. We propose that these proteins have two different conformations, which could explain their two localizations, a membranous (in the mycomembrane) and soluble (secretd into the cuture medium)
Nguyen, Huynh Nha Thi. "Développements en spectrométrie de masse pour l’étude des complexes biologiques." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF045/document.
Elucidation of non-covalent interactions of biological complexes takes on great importance for the understanding of cellular function. The purpose of this thesis is a further development of mass spectrometry (MS) for the study of these complexes, either by MALDI-MS (matrix-assisted laser desorption-ionization) or by ESI-MS (electrospray ionization). This work was focused on three main lines: i) study of the stoichiometry and the topology of SAGA HAT (Spt-Ada-Gcn5 Acetyltransferase, Histone Acetyl Transferase module) complex by chemical cross-linking coupled to MS; ii) monitoring the dimerization of the complexes formed by RAR-RXR (retinoic acid receptor - retinoid X receptor) with different DNAs; iii) measuring the dissociation constant of RXR-ligand complexes. The developed methodologies made it possible to expand the potential of MS and get insight into structure of biological complexes
Seyer, Alexandre. "Imagerie par spectrométrie de masse : développements méthodologiques et applications biologiques." Thesis, Evry-Val d'Essonne, 2010. http://www.theses.fr/2010EVRY0028/document.
My PhD’s work consisted in continuing the development of Mass Spectrometry Imaging (MSI) methods, in terms of methodology improvements but also through biological applications.The first part concerned the development of a novel sample preparation method dedicated to very small objects for chemical imaging, particularly for TOF-SIMS imaging. This method has been validated by studying different types of flavonoids in from seeds of Arabidopsis thaliana, with a size of 400 nm only. The second part, dedicated to biological applications, is divided into two sections. The first section includes two projects where the goals was to detect and locate, using TOF-SIMS imaging, the active molecule of an anti-acne cream in human skin sections, and a brominated flame retardant, the decabromodiphenyl ether, in target tissues in rats. In the second section, we have studied by MALDI-TOF and TOF-SIMS imaging the lipid absorption during the digestion, and finally, with the help of statistical analysis tools, we compared lipid profiles of healthy samples versus those from cystic fibrosis samples in a model animal of the disease.Through these projects, we have concluded that MALDI-TOF and TOF-SIMS imaging are two complementary techniques, and, when they are combined with statistical analysis, they can be powerful tools
Debois, Delphine. "Imagerie moléculaire d'échantillons biologiques par spectrométrie de masse ToF-SIMS." Thesis, Evry-Val d'Essonne, 2008. http://www.theses.fr/2008EVRY0014/document.
My PhD’s work has been devoted to the development of the emergent technique ToF-SIMS imaging. The first part of my work was dedicated to fondamental aspects with the use of a fullerene ion source as a primary ion beam or sputtering ion beam. We expected to realize 3D imaging. The second part of my work consisted to applications of the mass spectrometry imaging. Several application fields were studied, as archeology as with the analysis of patina of the Dogon statuary or chinese mummy hair. A third project was dedicated to the in situ biomarker research from human liver biopsies. The goal of this study was to identify a potential lipid biomarker of the non-alcoholic fatty liver disease. The last part of this manuscript is devoted to the in situ qualitative and quantitative analysis of surfactins (a family of heptacyclodepsipeptides) on a Bacillus subtilis swarming community. We combined ToF-SIMS imaging for qualitative analysis and localization of surfactins within the swarming pattern and MALDI-TOF mass spectrometry for the quantification of these species. The results ot this PhD’s work show that ToF-SIMS imaging could be applied to various fields of research as archeology, microbiology and medicine
Allegrand, Julie. "Spectrométrie de masse de biomolécules par photoionisation à pression atmosphérique." Thesis, Evry-Val d'Essonne, 2012. http://www.theses.fr/2012EVRY0010/document.
Atmospheric Pressure Photionisation (APPI) allows for the analysis of hydrophobic biomolecules which are unobservable with the common ionization techniques as electrospray ionization (ESI) or the matrix assisted laser desorption ionization (MALDI). This allows for the study of the interactions between a photon beam irradiating in the VUV thanks to a nebulisate and a mixture of molecules at atmospheric pressure. It generates numerous fragment ions, many of which are unobservable with the other in-source fragmentation techniques, and immediately provides structural information with no supplementary MS/MS experiment. The goal of this work was to spread the application of APPI to more or even less polar biomolecules and to elucidate their fragmentation pathways through a deepened understanding of reaction mechanisms involved. The experiments utilized a krypton lamp which provided rich mass spectra of various and even exotic fragment ions and characteristics of a wavelength fixed mainly at 10.0 eV and in a smaller proportion at 10.6 eV. The use of synchrotron radiation gave the advantage of adding a supplementary dimension to these APPI-MS spectra which is the wavelength variation (4-20 eV or 300-60 nm). This new parameter brings complementary information coming from the reactions never seen before with the known ion sources. The combined use of APPI source and synchrotron radiation is a very effective tool for the characterization of new molecules thanks to the large possibility of wavelength variation providing supplementary information to that obtained with the krypton lamp at the same wavelength
Mériaux, Céline. "Imagerie du système nerveux central par spectrométrie de masse MALDI." Thesis, Lille 1, 2011. http://www.theses.fr/2011LIL10059/document.
In recent years, MALDI mass spectrometric imaging has proved to be a powerful tool for biomarker research. This technology allows the analysis of a wide range of endogenous and exogenous compounds in tissue sections. Many developments need to be undertaken to improve the detection of molecules. The sample preparation, including chemical treatment and deposition of the matrix, is dependent on the tissue and molecules of interest and influences the quality of spectra and images. In addition, the bioinformatics tools such as multivariate analysis provide informations on the markers according to phenotypes. These steps are crucial for imaging applications in the field of biology. First of all, we focused on the development of new matrices suitable for MALDI imaging such as ionic matrices. Secondly, these developments have been applied to the invertebrate model, the medicinal leech, at embryonic and adult stages, to compare the biological mechanisms involved in the establishment of the central nervous system and nerve regeneration after injury of this system. Finally, studies of neurological damage have been undertaken to understand the key factors involved in the balance regeneration/degeneration. Thus, studies of human hippocampi samples have revealed the existence of proteins associated with a particular distribution corresponding to layers of neurons abnormally present in the hippocampus of epileptic patients
Ouedraogo, Richard. "La spectrométrie de masse : application à l'étude des cellules immunitaires." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM5062/document.
In view of the many advantages in terms of speed, cost , sensitivity and reliability of the MALDI -TOF mass, we thought we could apply it to the study of intact eukaryotic cells, in particular the study of cells immune . We have shown that this approach is applicable to the global analysis of eukaryotic cells including circulating immune cells. In addition, it allowed us to characterize the many faceted of human macrophage activation by analyzing the data with the R software library " MALDIquant " and specific algorithms. The protein/peptide fingerprint induced by the M1 agonists : IFN - γ , TNF , LPS and LPS + IFN - γ or M2 agonists : IL- 4 , TGF - β1 and IL- 10 are distinct to unstimulated macrophages and specific for each agonist. MALDI -TOF Mass spectrometry can then be used to characterize the subtypes M1 and M2 macrophages . In addition, fingerprints induced by extracellular bacteria ( group B streptococcus , Staphylococcus aureus ) are specific and closed to those induced by IL -4 . The responses of macrophages to intracellular bacteria (BCG, Orientia tsutsugamushi , Coxiella burnetii ) are also unique. Mass spectrometry MALDI -TOF of whole cell revealed therefore the multifaceted activation in human macrophages . Finally, preliminary results show that our approach could be used clinically for the analysis of circulating cells in the case of host-pathogen interaction
Le, Pogam-Alluard Pierre. "Analyses de lichens par spectrométrie de masse : déréplication et histolocalisation." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1S056/document.
Lichens are self-sustaining symbiotic partnerships comprising a fungus associated with a green alga and/or a cyanobacteria. This consortium produces unique secondary metabolites that are endowed with various biological activities. To harness this privileged chemodiversity, innovative mass spectrometry techniques were developed in the course of this study to accelerate the dereplicative holdup through both a minimal sample preparation and a decrease of the time of analysis. Two approaches were considered during this work: DART-MS and LDI-MS and their adequacy for lichen dereplication was assessed on a vast array of samples encompassing a wide range of metabolites. Both of them facilitated complete chemical profiles, respectively from unprocessed lichen material and crude acetone extracts. Since TLC still enjoys a wide-spread popularity among lichenologists, the advantages offered by TLC-ESI-MS hyphenation were evaluated as well. A second part of this manuscript focused on the histolocalization of lichen metabolites. For this purpose, LDI mass spectrometry imaging studies were undertaken on the crustose lichen Ophioparma ventosa. The phytochemical investigation of this species afforded the isolation of six naphthopyranones from its apothecia, four of them being new molecules. LDI-MSI revealed the distribution patterns of all the main metabolites of this lichen, reaching a spatial resolution of 50 μm. Most interestingly, the distribution pattern of imaged metabolites within the thallus is highly organized and is related to their ecological relevance. Joint strategies combining histolocalization and genetic investigation of lichen symbionts separated using laser capture microdissection were also considered. As such, an investigation of the biosynthesis of mycosporine serinol within Lichina pygmaea dissociated symbionts was initiated. Further analytical strategies such as X-ray powder diffraction are introduced in this thesis that contains six publications and two drafts to be submitted
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
Violet, Perrine. "Étude thermodynamique et experimentale du depôt ald (atomic layer deposition) de TaN et de son precurseur organometallique pdmat T, Ta[N(CH3)2]5, utilisé en microélectronique." Grenoble INPG, 2008. http://www.theses.fr/2008INPG0109.
The study of PDMAT vaporization and thermal cracking under vacuum of has been performed by using respectively Knudsen cell and tandem cells mass spectrometric method. The design and the validation of the reactor, specific to the study by mass spectrometry of the very reactive organometallic molecules in contact with the air, carried out during this thesis, are exposed. In parallel first TaN ALD starting from PDMAT and NH3 were realized in ALD new reactor in progress of optimization and were characterized by electronic microscopy and XPS. The confrontation of these two results makes it possible to propose reactions diagrams occurring at the time of the deposit of TaN in ALD reactor and to determine the structural and thermodynamic properties of identified molecules. These data are used in the various approaches of thermodynamic modeling of processes of growth starting from a gas phase
Monnier, Denis. "Étude des dépôts par plasma ALD de diélectriques à forte permittivité diélectrique (dits "High-k") pour les applications capacités MIM." Grenoble INPG, 2010. http://www.theses.fr/2010INPG0036.
The continuous decreasing size of integrated circuits in the field of microelectronics is now applied to passive components such as MIM (Metal/Insulator/Metal) capacitors. To increase the capacitance density of MIM capacitors, new materials with high permittivity are required to replace silica (Si02, E = 3. 9). Zr02 permittivity is around 47 for the tetragonal phase. Zr02 is deposited by PEALD. We studied the Zr02 deposition method with TEMAZ and ZyALD precursors. Thermodynamic properties of TEMAZ have been analyzed by Knudsen cell mass spectrometry. PEALD process parameters and post-treatments influence on the tetragonal zirconia synthesis have been investigated. Various characterisation methods (XRD, Raman spectroscopy, TEM, SIMS, XPS, electrical characterisation) were employed to establish an optimum between Zr02 films properties and deposition process performance
Jouve, Thomas. "Étude des déterminants de la puissance statistique en spectrométrie de masse." Phd thesis, Université Claude Bernard - Lyon I, 2009. http://tel.archives-ouvertes.fr/tel-00635493.
Quinton, Loïc. "Caractérisation de toxines peptidiques par spectrométrie de masse à haute résolution." Phd thesis, Ecole Polytechnique X, 2006. http://pastel.archives-ouvertes.fr/pastel-00002201.
Salque-Moreton, Guillaume. "Etude d'aérosol atmosphérique par spectrométrie de masse à très haute résolution." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENU013/document.
Atmospheric aerosol has an important impact on the radiative balance of Earth. Organics compounds represent the major fraction of atmospheric aerosol particles; a large part is still not well characterized. A detailed understanding of the sources, transformations processes and fates of organics aerosols is needed. This work investigates the ability of the ESI-Orbitrap to characterize organics molecules of aerosol. Firstly, experimental and analytical methods were developed to unveil mechanistic ambiguities that were previously shown. Methacrolein (MACR) and methyl vinyl ketone (MVK) (the two main gas phase atmospheric oxidation products of isoprene) were known to form oligomers and secondary organic aerosol (SOA) upon aqueous phase OHoxidation and subsequent water evaporation. For the two precursors, ESI-MS analysis of the reacting solutions brought clear evidence for the formation of oligomer systems having a mass range of up to 1400 Da.. Taking advantage of the regularities observed in the oligomer systems, the ESI-HRMS data were used to propose stoichiometries for more than 75% of the observed signal. Moreover, we show here that MACR oligomers aging give rise to HULIS production. In addition, global estimates of secondary organic aerosol (SOA) formation flux show that current descriptions miss a large fraction of the sources. This gaping underestimation has been linked to a poor understanding of aerosol functionalization in the atmosphere and lead to the formation of a new conceptual framework for the description of the aerosol, based on volatility versus polarity plots. This new framework is almost exclusively based on High Resolution Time of Flight Aerosol Mass Spectrometer(HR-Tof-AMS) data, as this instrument gives access to average H:C, N:C and O:C ratios for the bulk aerosol. The AMS estimates for O:C and H:C ratios are thus based on heavy fragmentation of organics followed by stoichiometry attribution on those fragments. Given the resolution of the HR-ToF-AMS, such an attribution is not feasible above a certain mass, making fragmentation a necessary aspect of the measurement. Conversely, Orbitrap-HRMS provide a resolution of 100,000 at m/z 400, with a mass range 50 – 2000 amu, enabling stoichiometry retrieval up to higher masses than the AMS. Coupled to a “soft” electrospray ionization method, Orbitrap-HRMS gives O:C and H:C ratios on entire molecules in the analysed mixture. We used samples from three contrasted field campaigns: the two first at an urban kerbside site in summer and in winter, the third one in the roadway vicinity (Grenoble, France). Accelerated Solvent Extraction provides a clear overview of the chemical composition of organic extracts from aerosol particles collected at different season at an urban site. The elemental composition was obtained within 2-5 ppm, on the range 150-300 m/z. However, this study shows that both ionization polarity were needed to get a complete picture of the chemical composition of the samples. We showed that Esi-Orbitrap-HRMS allows to compute a statistical distribution of the elementary ratios that is different from a simple average value. Keywords: HRMS, SOA
Delobel, Arnaud. "Spectrométrie de masse par nébulisation : électronébulisation et photoionisation à pression atmosphérique." Evry-Val d'Essonne, 2004. http://www.theses.fr/2004EVRY0038.
Two ionization methods used in the field of mass spectrometry were studied during this PhD work. Both of these methods – electrospray and atmospheric pressure photoionization – are based on the spraying of a sample solution. Electrospray proved to be able to study macromolecular noncovalent complexes between proteins and metal cations. In the first case, interactions between model proteins and organic gadolinium complexes proved to be weak and aspecific. In the second case, our results showed that a chloroplastic protein involved in photosynthesis – CP 12 – was eable to specifically bind some particular metal cations. Dissociation constants were calculated and important insights into the structural features of CP 12 were obtained. Atmosphéric pressure photoionization, which had sor far never been used for the analysis of biomolecules, happened to be very promising. Duriing the analysis of peptides, singular gragmentation patterns were observed. Very important results, especially from a structural point of vue, were obtained for phosphatidylcholiines and globotriaosylceramides. Underlying physico-chemical processes were tackled, and the rôle of both electron-ion reactions and radical processes were outlined. The results of this PhD work higlilighted the crucial rôle of the ionization methods based on spaying of samples in biomolécular analysis. Mass spectrometry is in many cases and analysis method of choice in molecular biology
Touboul, David. "Imagerie biologique par spectrométrie de masse. Aspect fondamentaux, méthodologies et applications." Evry-Val d'Essonne, 2006. http://www.theses.fr/2006EVRY0010.
My PhD’s work has been completely devoted to develop new imaging mass spectrometry (IMS) techniques, called MALDI-TOF imaging and cluster-TOF-SIMS imaging. The first part of this manuscript was dedicated to instrumental developments. For MALDI-TOF imaging, the goals were to optimize the matrix deposition and to develop methods for identifying biomarkers. For TOF-SIMS imaging, the objectives were to test new cluster ion sources and to perfect structural analysis. Complementarities between these two innovative imaging techniques were also demonstrated. The second part was devoted to biological applications (Duchenne Muscular Dystrophy, Fabry Disease, saponine effects on human melanoma cells) or to surface analysis (archaeological samples and OPLC-IMS). The results of this PhD work enlightened the fact that MALDI-TOF and cluster-TOF-SIMS imaging methods are new powerful tools to study drug distribution and to find new biomarkers in biological tissues
Guy, Philippe. "Utilisation de la spectrométrie de masse pour l'étude structurale des protéines." Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10085.
Dupré, Mathieu. "Développements méthodologiques en spectrométrie de masse LDI pour l'analyse de peptides." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20069/document.
The advent of proteomics and metabolomics require the development of highly efficient analytical tool in order to detect and identify peptides and proteins as well as small organic compounds present in biological media. Due to its sensitivity, specificity and speed of data acquisition, Matrix-Assisted Laser Desorption/Ionization constitutes one of the major ionization methods in mass spectrometry suitable for the analyses of biomolecules. However the sensitive detection of low molecular weight compounds (<700 Da) is most of the time troublesome, being hampered by the production of matrix ions in the low mass range. In that case, the potency of various alternative LDI techniques based on inert ionization promoting substrates was evaluated for the detection of synthetic peptides presenting wide sequence diversity. Silicon and titanium based materials exhibiting different physico-chemical properties were probed for LDI-MS and LDI-MS/MS analyses of the designed model peptides. These methods, which were devoted of the use of any organic matrix, were optimized through a large set of experiments, taking particular attention to detection sensitivity and reproducibility. Spectral discrimination was another matter of concern, especially in the case of peptide mixture analyses which is encountered in proteomics for tryptic digest elucidation. The performances of the design LDI methods were compared with the original MALDI technique for peptide detection and sequencing from various samples i.e. pure and mixed synthetic peptides, and four tryptic digests issued from Cytochrome C (12 kDa), β-Casein (24 kDa), Bovin serum albumin (BSA, 66 kDa) and fibrinogen (340 kDa). A second research topic dealing with peptide sequencing by MS/MS technologies was pursued in order to contribute to the knowledge of the fragmentation rules. Vibrational activation methods through various mass analyzer configurations (MALDI-TOF/TOF, ESI-QqTOF) were investigated. Specific dissociation behaviors were extracted from the recorded MS/MS data sets. The presence of basic residues, provided that they are not located at the peptide C-terminal end, triggered specific backbone fragmentation in competition to the expected bx-yn pathway. This was found to be a critical issue to be considered by sequencing softwares
Seng, Piseth. "Application de la spectrométrie de masse MALDI-TOF en microbiologie clinique." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM5033/document.
The objective of this thesis is to apply the method of bacterial identification by MALDI-TOF MS in daily practice in a routine clinical microbiological laboratory. Firstly, we prospectively evaluated the performance and the cost-effective of bacterial identification by MALDI-TOF in comparison with conventional phenotypic identification methods. During a 16-week study, we compared the performance of MALDI-TOF with conventional techniques of identification including Gram staining, API ANA identification strip and automated identification using the Vitek 2. The unmatched identifications between MALDI-TOF and conventional methods were resolved by molecular identification. In this study, we showed that MALDI-TOF was an effective tool and less expensive for the rapid identification of bacterial species in clinical microbiology laboratory. MALDI-TOF can be used in first intention for identification before Gram staining or other phenotypic identification techniques based on physicochemical properties of bacteria. Secondly, we retrospectively evaluated the performance and the cost-effectiveness of the exclusive use of MALDI-TOF in bacteriological diagnosis in comparison with conventional phenotypic identification. 11-year retrospective analysis of data showed that MALDI-TOF was efficient and completely adapted for the routine identification of bacterial species. We also showed that MALDI-TOF had capacity to identify bacterial species that were rarely involved in human diseases. This technique could be an alternative to molecular methods in the clinical laboratory
Maire, Florian. "Étude des dendrimères polyamidoamines par spectrométrie de masse et mobilité ionique." Rouen, 2010. http://www.theses.fr/2010ROUES018.
In the first part of this work, we report the formation of unexpected ions during mass spectrometry analysis of a first-generation polyamidoamine dendrimer using an electrospray ionization source in negative ion mode. The study of these ions, corresponded to an increase of 12 Da, showed that an electrical discharge in the electrospray source was the origin of these artefacts. In the second part, we use ion mobility coupled with mass spectrometry as an analytical technique to determine the size of polyamidoamine dendrimers up to generation 3. Our results showed a good agreement with those obtained by molecular models and literature values. Furthermore, polyamidoamine dendrimer isobaric ions were dispersed by the combination of ion mobility and mass spectrometry. The third part deals with the study of non-covalent complexes involving first-generation polyamidoamine dendrimer and single stranded oligonucleotides. MS/MS fragmentation of these complexes was different according to the charge state of the complex and the oligonucleotide length. Relevant information, concerning complex stability in the gas phase, was obtained only for larger non-covalent complexes
Bodet, Pierre-Edouard. "Recherche de biomarqueurs glucidiques de mucopolysaccharidoses et étude de la physiopathologie." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLE001/document.
The identification of biomarkers remains one of the main challenges for analytical sciences and a major stake for clinical research. Glycosaminoglycans (GAGs) have been identified as potential biomarkers of mucopolysaccharidoses (MPS) belonging to rare genetic diseases with often a deadly issue. These pathologies are due to a deficiency in one of the enzymes responsible for GAGs catabolism. This enzymatic defect results in the accumulation of partially catabolized GAGs in organism and leads to neurodegeneration for the most severe forms of the disease. GAGs are complex polyanionic polysaccharides involved in numerous physiological processes in mammals. Their study remains a challenging task because of their high structural heterogeneity and their low biodisponibility, besides the lack of dedicated analytical tools. Our aim was to detect and quantify these compounds in biologic fluids such as urine and cerebrospinal fluid, and to elucidate their structures by mass spectrometry. This study focused on heparan sulfate (HS) oligosaccharides, as potential biomarkers of MPS featured by neurological manifestations (MPS I, IIIB and IIIC), and possibly responsible of lesions in the central nervous system. An experimental strategy allowing the extraction of HS oligosaccharides from biological fluids was implemented, thereby the structures of urinary heparan sulfate oligosaccharides were deciphered, leading to possible biomarkers candidates of MPS IIIB and IIIC. These compounds could be useful for diagnostic and patient follow-up that are currently lacking for the monitoring of therapeutic assays. In vitro exposition of different cerebral cell types to HS oligosaccharides was carried out to establish the relation between the structure of oligosaccharides and neuropathological effects. These studies highlighted several cellular processes that could be involved in neurodegeneration and constitute new therapeutic targets
Shenar, Nawar. "Spectrométrie de masse par désorption/ionisation laser de peptides modèles : applications en protéomique." Montpellier 2, 2008. http://www.theses.fr/2008MON20150.
Hupin, Sébastien. "Caractérisation d’auto-assemblages de polyoxométallates hybrides organiques-inorganiques par spectrométrie de mobilité ionique couplée à la spectrométrie de masse." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMR062.
Polyoxometalates (POM) are anionic compounds formed by the assembly of metal oxide polyhedra {MOy}, (with M, MoVI or WVI) linked together by oxygen atoms. POM thus form a remarkable class of nanometric inorganic metal oxide clusters, with a wide variety of charges and structures. It is possible to form hybrid systems including the inorganic part of the POM and a grafted organic part, allowing new functionalities to be added to the POM, such as selfassembly. We have dedicated this thesis work to the characterization of standards, hybrid and self-assembled POM systems by mass spectrometry coupled to ion mobility spectrometry (IMS-MS). A first experimental approach using drift tube ion mobility spectrometry (DTIMS) allowed us to determine the collision cross sections (CCS) of standard POM in helium and nitrogen. The CCS of the POM standards then allowed us to calibrate an IMS cell of a Travelling Wave ion mobility instrument (TWIMS). The analysis by IMS-MS of organic-inorganic hybrid POMs alone or in the presence of transition metal cations revealed the presence of self-assembled triangular [POM3·cation3], square [POM4·cation4] or pentagonal [POM5·cation5] systems with different charge states. CCS values of these self-assemblies was estimated from the calibration of the TWIMS cell. Using a theoretical approach, we modelled several standard POM structures with and without tetrabutylammonium counterion (TBA+) using density functional theory (DFT). The optimized structures were used to determine theoretical CCS using the trajectory method of the MOBCAL software, in which we incorporated molybdenum and tungsten atoms for which we optimized new Lennard Jones potential parameters. The correspondence of experimental and theoretical CCS of standard POM structures offers new possibilities for structural attribution of self-assembled hybrid POM by coordination in the presence of metal cations
Daubenfeld, Thorsten. "Etude de complexes protéiques non covalents par spectrométrie de masse FT-ICR." Phd thesis, Ecole Polytechnique X, 2006. http://pastel.archives-ouvertes.fr/pastel-00002922.
Dron, Julien. "Analyse fonctionnelle par spectrométrie de masse tandem : application aux aérosols organiques atmosphériques." Phd thesis, Université de Provence - Aix-Marseille I, 2008. http://tel.archives-ouvertes.fr/tel-00308753.
Joly, Laure. "Couplage spectroscopie optique - spectrométrie de masse : propriétés optiques et photofragmentation de biomolécules." Thesis, Lyon 1, 2009. http://www.theses.fr/2009LYO10085.
This manuscript discusses optical properties and photofragmentation of gas phase biomolecules. These experiments are performed with a quadrupolar ion trap coupled to a UV-visible tunable laser. Molecules are isolated at the center of the trap, and irradiated by the laser beam. The most intense relaxation channel observed for multiply negatively charged ions is electron emission. This loss of one electron leads to radical anion formation. The first part of this manuscript is dedicated to the study of the mechanisms leading to the electron loss. Photodetachment experiments performed in Lyon were completed by photoelectron spectroscopy experiments performed in Karlsruhe (Pr. Kappes). The radical anion production has an important analytical potential. One of the main objectives of this work was to study the reactivity of this radical anion and to show the interest of radical fragmentation for the structural analysis of peptides. An other objective was to probe electronical properties of gas phase peptides and proteins. The electron detachment yield is recorded as a function of laser wavelength. We have determinated optical fingerprints for neutral, deprotonated and radical chromophores localized in the heart of proteins. These results are compared to computational methods (TD DFT)
Mehmood, Shahid. "Caractérisation structurale de protéines membranaires par échange hydrogène/deutérium spectrométrie de masse." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00767335.
Sabir-Bagag, Aïcha. "Photoionisation et spectrométrie de masse : un nouvel outil pour l'identification de biomolécules." Thesis, Evry-Val d'Essonne, 2008. http://www.theses.fr/2008EVRY0041/document.
My PhD’s work has been completely dedicated to develop new ionization source in mass spectrometry: the atmospheric pressure photoionization (APPI). This work is developed on two main areas. On the one hand, it aims to apply this method to new family of biomolecules. On the other hand, we report a comprehensive study on the ionization mechanisms in APPI. The first part of this manuscript offers a better understanding of the behaviour of the biological molecules under VUV radiation and atmospheric pressure. Indeed, we were able to say that polar and high molecular weight biomolecules could be easily photoionizable. Moreover, this work allows studying the effect of the medium (solvent) on the photoionization mechanism to be studied. It is possible to control the orientation of the observed reactions and to choose a particular type of molecular ion. We observed extensive and peculiar fragmentations which have never been detected with classical ionization techniques. The originality and innovative approach of this experience led us to transfer it to a UV beamline of the Synchrotron SOLEIL. Using an accordable source will certainly enhance the versatility of the ion source
Przybylski, Cédric. "Développement de nouvelles méthodes d'analyse d'oligosaccharides anioniques bioactifs par spectrométrie de masse." Thesis, Evry-Val d'Essonne, 2014. http://www.theses.fr/2014EVRY0001.
The non-Covalent interactions between proteins and anionic polysaccharides such as glycosaminoglycans (GAGs) are involved in several physio-Pathological processes such as cell signalling and recognition, bacterial and viral infections or during cancer progression. One of the obstacles to get the molecular mechanisms involved during these interactions hold in the structural information deciphering within GAG's sequences. This task is delicate especially because of variable level of acetylations and sulfations, constituting important bottleneck in the research advances of the glycobiology field. To bypass these restrictions, accurate and innovative analytical methods such as mass spectrometry (MS) provide numerous advantages. During this Ph.D training, three original MS based approaches have been developed. The first dealt with the synthesis of new ionic liquid matrices, which both restrict desulfation process and favour the homogeneous deposits for UV-MALDI-TOF analysis. The second way used a soft recently introduced ionization method, desorption electrospray ionization (DESI) allowing direct analysis in ambient conditions of anionic oligosaccharides or under complexes with protein. Finally, the third involved the making of protein or saccharide chips for the analysis of protein / GAG complexes using the hyphenation of surpface plasmon resonance with MS (SPR-MS). Thos coupling allows real time monitoring protein / GAG complexes formation, their dissociation constant determination and the direct detection of protéic as wall as saccharidic ligands by UV-MALDI-TOF
Courrier, Benoît. "Caractérisation par spectrométrie de masse des molécules neutres induites par ablation laser." Metz, 2000. http://www.theses.fr/2000METZ057S.
Identification of neutral molecules emitted during laser materials interaction is one of the research axes developed by the Laboratoire de Spectrométrie de masse et chimie laser (LSMCL). Characterization of neutral molecules emitted during laser ablation was achived by developing a laser ablation/quadripolar mass spectrometer coupling system via gazeous chromatrography (GC/MS). The laser pyrolisis results were compared firstly those obtained by thermal pyrolisis GC/MS. They showed the strong dependance of power, the formation of aggregates and the mecanisms of decarboxylation for organic acids used as MALDI matrix. Due the introduction mode of neutral species into the chromatographic column, they was a weak sensitivity more especially for low density. The purpose of our studies was to develop and to carry out a device for identification of the neutral molecules emitted during laser ablation by increasing the detection sensitivity. Gazeous chromatography was removed and we replaced a mass spectrometer. This one is more sensitive than the GC/MS because several ionization modes can be used (electron impact EI and chemical ionization CI). When thesis is devided in two parts : the first one is confidential and will relate the presentation and the development of the device ; the second part is be devoted on the one hand, to the studied of the laser ablation of synthetic polymers and on the other hand, to the laser ablation of organic compounds used as MALDI matrix, in order to identify neutral molecules emitted
Saravanamuthu, Gunalini. "Détermination des sites d'interaction des protéines par spectrométrie de masse MALDI-TOF." Paris 6, 2011. http://www.theses.fr/2011PA066730.
Ludwiczak, Pascal. "Adaptation des mycobactéries à leur environnement : nouvelles approches par spectrométrie de masse." Toulouse 3, 2002. http://www.theses.fr/2002TOU30171.
Mycobacteria are pathogenic agents, responsible of Tuberculosis. Yet, the molecular bases of this pathology are yet not well defined and mycobacteria have developed many important and complex penetration mechanisms, that complicate the fight against infection. Moreover, virulent mycobacteria induce an active disruption in the cellular maturation and communication mechanisms, and thus survive and multiply sheltered from defenses of the host immune system. Thus, adaptation of the bacilli to their environment is today presented as one of the principal keys in the understanding of the tuberculosis pathology. .
Ndiaye, Séga. "Recherche des partenaires de l'amyloïde-bêta 1-42 par spectrométrie de masse." Paris 6, 2011. http://www.theses.fr/2011PA066540.
Bui, The Thuong Mathieu. "Développement d'une méthode d'analyse des milieux réactionnels par spectrométrie de masse APPI." Strasbourg, 2011. http://www.theses.fr/2011STRA6242.
The aim of the project is to set up a universal method, easy to implement, that gives a rapid and precise information on the composition of the reaction mixture (identification and quantification of compounds of interest) and to evaluate the scope of the method. The principle of this method, [TMOA-APPI-MS], relies on the labeling of a compound of interest by an organic molecule that is chemically inert and owns selective ionization by APPI. In this method, the label (trimethoxybenzene) is selectively ionized and only the labeled molecules are detected. The label decreases the influence of the other functions on the molecule or in the reaction mixture and allows a standardization of the analysis conditions. The method was first compared with classical techniques (NMR, GC, HPLC) in a carbonylative Sonogashira coupling. The study of more complex reaction mixture with amines was then undertaken. This study enabled the optimization of reaction conditions for the synthesis of heterocycles starting from a labeled ynone. A reaction of deethylation of triethylamine catalyzed by platinum was discovered by the method [TMOA-APPI-MS]. A study to validate the discovery of "new reactions" was then undertaken. Known and new reaction conditions were applied to labeled model substrates with alkyne or diyne functions. The reactions were analyzed by the method [TMOA-APPI-MS], in order to ensure its ability to detect new transformations. This systematic screening showed that silver selectively catalyzes the hydration of terminal alkynes
Wisztorski, Maxence. "Développements en imagerie par spectrométrie de masse et applications aux modèles invertébrés." Lille 1, 2006. https://ori-nuxeo.univ-lille1.fr/nuxeo/site/esupversions/b2cd98ef-2445-48bc-9462-f547716f3776.
Guigues, Elodie. "Mesure en ligne des produits de fission gazeux par spectrométrie de masse." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4706.
In order to increase fuel rod performances, the basic mechanisms that promote gas (i.e. He, H2, Kr and Xe) release from irradiated nuclear fuels must be studied. In this context, the CEA fuel study department at Cadarache decided to improve its experimental facility devoted to fuel behaviour under thermal transient by modifying the existing annealing device, called MERARG-II.The first part of this dissertation adresses the fuel gas release monitoring from irradiated fuel during thermal transient. The device choice leads to a quadrupole mass filter as mass analyser according to the specification requirement, i.e. isotopic identification of Xe, Kr and masses at 4 and 2 u. It is commercialized Residual Gas Analyser, mounted in a small-volume vacuum chamber requiring adaptations to be connected to the MERARG II line. The resolution and sensitivity of the mass spectrometer have been evaluated. The calibrated device is being installed in MERARG II replica.The second part of this dissertation relates adaptation to low-mass analysis of an RF 3D ion trap operated a Fourier Transform mode. Theoretically, using this operating mode, the lower the mass, the higher the resolution. More particularly, an ion injection device and its operating mode are studied in order to gain position and velocity distributions of confinable ions. The knowledge of these initial conditions is of a great concern as they fix the signal dynamic (peak height) and the signal fluctuation, respectively. This feasibility study, using simulation, allows us to obtain the optimal values of trap operating condition for 1-6 u mass injection and confinement with high resolution
Douix, Suzie. "Caractérisation de perfluorocarbones (CₓFᵧ, PFCs) par spectrométrie de masse et spectroscopie VUV." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS523/document.
Perfluorocarbons compounds have both hydrophobic and lipophobic properties. They have been manufactured since the 1950s, and widely used in many industrial applications. However, they are persistent, bioaccumulative compounds with long atmospheric lifetimes. They are considered to be potent greenhouse gases, and are supposed to be mainly degraded by photolysis in the upper atmosphere. A work of physicochemical characterization of two perfluorinated compounds was realized on the PFOA and PFOS. They have been found to be the final compounds of degradation of the majority of perfluororinated compounds. VUV spectroscopy and mass spectrometry experiences have been undertaken to identify their relaxation pathways after photoactivation. A methodology based on the coupling of synchrotron radiation and mass spectrometry was developed to perform absolute cross section measurements and was apply to the compounds of interest. These measurements have been used to determine their photolysis rates and atmospheric lifetimes according to the altitude
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