Teses / dissertações sobre o tema "Single particle ICP-MS/MS"
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Lui, Kwok-on, e 呂國安. "Single particle analysis by time-resolved ICP-MS measurement". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46582630.
Texto completo da fonteGivelet, Lucas. "Détection et caractérisation des nanoparticules de dioxyde de titane dans les aliments par AF4-ICP-MS et Sp-ICP-MS". Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAI037/document.
Texto completo da fonteThe thesis focuses on the development of methods for the titanium dioxide (TiO2) nanoparticles (NPs) characterization in food products. The study was separated distinctly into two axes. The development of the AF4-ICP-MS (I) method within the CEA Nano-Safety Platform in Grenoble and the development of the Sp-ICP-MS (II) method within the Food Safety Laboratory of the Anses in Maisons-Alfort.For the first axis, the electrostatic interactions between the particles and the AF4 membrane were studied. The surface charge (zeta potential) was measured for particles and membranes depending on several solvent parameters such as pH, ionic strength and the presence of surfactants. Following the several analyzes carried out, several solvent conditions have been identified as promoting the electrostatic repulsion between the particles and the membrane, which will make it possible to reduce the losses of particles at the level of the membrane. Several conditions were therefore directly tested for NPs analysis of TiO2 in AF4-ICP-MS. It has thus been shown that the conditions favoring electrostatic repulsions make it possible to improve the efficiency of the particles at the level of the AF4 system. However, the analyzes also showed that the TiO2 NPs were not sufficiently dispersed to obtain a reliable size distribution.The second part of the thesis aimed at first optimizing the data treatment of the Sp-ICP-MS method. Several improvements have been made such as the automatic calculation of the background-particle threshold, the calculation of the transport efficiency or the addition of quality control parameters. This data treatment was then compared to a software dedicated to analyzes by Sp-ICP-MS and made it possible to highlight that the internal spreadsheet gives results with a better accuracy, while providing additional parameters.In a second time an optimization of the Sp-ICP-MS method was carried out. Several parameters were therefore evaluated such as the choice of the titanium isotope, the acquisition time, the type of solvent to disperse the particles, as well as the sample collection mode and its flow rate.Finally, several foods were analyzed after setting up an extraction protocol for NPs. The results obtained made it possible to determine a size distribution of the NPs of TiO2 present in the samples
Mozhayeva, Darya [Verfasser]. "Single particle ICP-MS : capabilities of microsecond time resolution and coupling to capillary electrophoresis / Darya Mozhayeva". Siegen : Universitätsbibliothek der Universität Siegen, 2019. http://d-nb.info/1193252180/34.
Texto completo da fonteCraig, Grant. "Improving the utility of LA-ICP-MS for isotope ratio analyses of single particles with application to uranium oxide". Thesis, Loughborough University, 2016. https://dspace.lboro.ac.uk/2134/21518.
Texto completo da fonteSchmidt, Benita. "Detection and Characterisation of Nanoparticles using Inductively Coupled Plasma Mass Spectrometry". Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/20162.
Texto completo da fonteIn this doctoral thesis an analytical method for characterising metal nanoparticles (NPs) was developed and its application for investigating natural samples verified. An analytical system consisting of a microdroplet generator (MDG) used in combination with a pneumatic nebuliser (PN) and an inductively coupled plasma mass spectrometer (ICP-MS) proved capable of quantitatively and qualitatively identifying NPs. The MDG was used to establish the calibration function for mass quantification of the metal present in the sample NPs introduced via the PN. The major advantage of this configuration is that the MDG generated droplets of tailored size for any given metal while offering a 100 % transport efficiency. The introduced mass correlated with signal intensities of NPs and thus the microdroplet generated droplets could be used for calibration purposes without the need for any reference material. Thus, the tedious and error-prone nebuliser efficiency determination step that is required when determining the NP metal content using the single particle mode ICP-MS (spICP-MS) approach, could be avoided. With this dual sample introduction method, the sizes and concentrations of a range of standard silver (Ag) NPs and gold (Au) reference NPs were determined with high accuracy. Additionally, together with a new commercially available ICP-time of flight-MS (ICP-TOF-MS) the characterisation of Ag- and Au-NPs was carried out in various matrices: In hydrochloric (HCl) and nitric acid (HNO3) at a range of concentration and in different elemental environments. In the presence of matrices, it was found that the size characterisation of the NPs is correct within the standard deviation.
Sötebier, Carina Anna. "Charakterisierung von Silber-Nanopartikeln mit der Feldflussfraktionierung, Hochdruckflüssigkeitschromatographie und der induktiv gekoppelten Plasma-Massenspektrometrie". Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2017. http://dx.doi.org/10.18452/17743.
Texto completo da fonteIn this work, four different methods for the separation, identification, and quantification of silver nanoparticles (Ag-NP) were developed. Using asymmetric flow field-flow fractionation (AF4) in combination with inductively coupled plasma mass spectrometry (ICP-MS), a good separation and high recovery rates were found. A systematic investigation of possible sample losses during the method optimization showed that Ag+ ions caused the highest loss and only negligible amounts of Ag residues on the membrane were found. For citrate-stabilized Ag-NP, hollow fiber flow-field flow fractionation (HF5) analyses achieved good results for the separation and calculation of the hydrodynamic diameters. In order to determine the particle number size distribution and the geometric diameter for samples in unknown matrices, isotope dilution analysis (IVA) was successfully combined with single particle ICP-MS. Additionally, a high-performance liquid chromatography (HPLC)-IVA-ICP-MS approach was developed, which was able to separate and quantify NP and their corresponding ions. A comparison of the methods showed that a combination of different approaches is necessary to obtain all relevant information. Finally, the methods were applied to analyze the environmental behavior of Ag-NP in a humic acid (HS) suspension. Here, first stabilization effects in terms of the Ag concentration and particle number concentration were detected. Using HF5 and HPLC for the analysis of small NPs in HS, a modification in the form of a second, smaller NP signal was observed.
Bastardo-Fernandez, Isabel. "Vers une fiabilité améliorée de la détermination de (nano)particules de TiO2 par single particle inductively coupled plasma-mass spectrometry : application à la caractérisation des aliments et aux études de migration". Electronic Thesis or Diss., Maisons-Alfort, École nationale vétérinaire d'Alfort, 2024. http://www.theses.fr/2024ENVA0001.
Texto completo da fonteThis PhD project aims primarily to improve the reliability of the characterisation of TiO2 nanoparticles (NPs) and to gain knowledge of the food additive E171 and in real-life applications such as migration of these NPs from food packaging. In the first part of the study (to be carried out at Anses), a new approach for TiO2 NPs characterisation will be developed and optimized by using the single particle approach in combination with inductively coupled plasma-triple quadrupole mass spectrometry (Sp-ICP-QQQMS). For this purpose, the most critical analytical parameters, such as the transport efficiency (TE) calculation methods and the sample introduction system will be assessed under different working conditions (e.g. reaction gas, choice of isotope). In the latter case, two high efficiency sample introduction systems (APEX type) will be critically compared. Further, a complementary Sp approach based on ICP-high resolution MS (Sp-ICP-HRMS) will be developed at LNE. The novelty in this case will be the use of a high resolution (magnetic sector field) ICP-MS for detection, which is the state-of-the art technique for trace and ultra-trace metals determination of highly interfered elements such as the case of Ti. An in-house injection system will also be optimized to increase the transport efficiency and sensitivity. Method validation by inter-laboratory comparison between LNE and ANSES will be achieved here. A truly added value of the project will be the assessment of the measurement uncertainty related to TiO2 NPs characterization by both Sp-ICP-MS (QQQ and HR) approaches. The uncertainty calculations will take into account, not only the experimental reproducibility and the uncertainties of each variables required to convert ICP-MS signal into NPs size and concentration, but also and for the first time, the effect of the choice of the cut-off to discriminate the ICP-MS ionic signal from that of NPs. The effect of deviations from the spherical shape on the sizes will also be explored and compared with scanning electron microscopy (SEM), which is the reference method for NPs characterisation. The project also aims at the preparation and exhaustive characterization of a real-life (food additive) reference material containing TiO2 nanoparticles. A feasibility study of the development of an E171-based RM under a suspension form will be carried out. For this purpose, a representative E171 sample will be prepared and fully characterized by a panel of complementary techniques, such as SEM, Sp-ICP-QQQ MS, Sp-ICP-HRMS, X-ray diffraction (XRD) to accurately assess the main parameters of interest, such as the median and mean diameter, size distribution, fraction of nanoparticles, chemical impurities and crystallographic fraction. Finally, both analytical approaches developed at Anses and LNE, including the developed method for global uncertainty assessment, will be applied to the study of the transfer of TiO2 NPs from food packaging. All along the project, the size data obtained by using the newly developed “single particle” based approaches for TiO2 NPs characterisation will be compared to SEM measurements, which is the reference method for size in this study field. Food packaging migration studies is indeed a selected case study where Sp-ICP-MS has the potential of supplying additional information compared to other instruments, such as: particle concentration, proportion of particulate vs. dissolved form, which are of importance for migration as well as to improve risk assessment studies
Chan, Ka-lok, e 陳嘉樂. "Single droplet generation by dripping-mode electrospray for ICP-MS measurement". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/202348.
Texto completo da fonteLöhr, Konrad. "Arraying of single cells for high throughput elemental analysis using LA-ICP-MS". Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/20573.
Texto completo da fonteLaser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is increasingly used for single-cell analysis. However, a more widespread use of LA-ICP-MS in single cell analysis is hampered by its low throughput. Hence, in this work the throughput of single cell LA-ICP-MS was studied and improved. First, the two possible ablation modes, imaging and single spot analysis (SSA) of single cells using a large laser spot, are compared regarding their analytical figures of merit (signal to noise, precision, accuracy, throughput), as well as regarding ease of operation and data evaluation. For that, adherent 3T3 fibroblast cells were stained with two metal dyes and several dozen cells were measured using both modes. SSA showed superior characteristics regarding throughput and detection limits. Moreover, it was shown that >400 cells must be analyzed to reach satisfactory statistics for a quantitative comparison of results, which would have been too laborious. Thus, a single cell arraying step was integrated to enable automated LA-ICP-MS analysis. Two different arraying methods were evaluated: First, arraying via hydrodynamic front trapping of cells using a microfluidic device was tested, but clamping of soft PDMS-chips prevented successful arraying and it was concluded that a major redesign of the chip is necessary. Secondly, and a novel technology relying on a microdroplet arrayer in conjunction with image recognition of cells was tested and a moderate arraying throughput (550 cells per hour) and an unprecedented single-cell accuracy (>99%) was found. In a proof of principle experiment, a cell array of THP-1 suspension cells was analyzed using LA-ICP-TOF-MS and endogenic and exogenic isotopes of individual cells were detected for the first time simultaneously as isotopic fingerprints of cells with detection limits as low as hundred attogram. Finally, these results were compared to the currently more commonly used analysis method single-cell (sc)-ICP-MS.
Stenberg, Anna. "Isotopic analyses of biological materials by single and multi-collector sector field ICP-MS". Licentiate thesis, Luleå, 2004. http://epubl.luth.se/1402-1757/2004/011.
Texto completo da fonteLöhr, Konrad [Verfasser], Michael [Gutachter] Linscheid e Ulrich [Gutachter] Panne. "Arraying of single cells for high throughput elemental analysis using LA-ICP-MS / Konrad Löhr ; Gutachter: Michael Linscheid, Ulrich Panne". Berlin : Humboldt-Universität zu Berlin, 2019. http://d-nb.info/1197061045/34.
Texto completo da fonteKerr, Samantha Louise. "Enhancing nucleic acid detection using inductively coupled plasma mass spectrometry, by means of metal and nano-particle labelling". Thesis, Loughborough University, 2008. https://dspace.lboro.ac.uk/2134/4641.
Texto completo da fonteChemnitzer, René. "Intercalation von Stickstoff und Wasserstoff in Sr2N sowie ortsabhängige Feststoffcharakterisierung mit Laserablation". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2006. http://nbn-resolving.de/urn:nbn:de:swb:14-1154519820856-41799.
Texto completo da fonteMaknun, Luluil. "Development of mass spectrometric analytical methods for the determination of iron complexes in plants and bacteria and for the determination of cobalt using bimetallic nanoparticles". Electronic Thesis or Diss., Pau, 2023. http://www.theses.fr/2023PAUU3039.
Texto completo da fonteThe research focuses on an analytical method development using chromatography coupled to mass spectrometry for the analysis of low molecular weight iron complexes. In the second part, the study explores the utilization of bimetallic nanoparticles for Co2+ detection.In the first part, a method using liquid chromatography with two detector mass spectrometry, i.e., electrospray high-resolution accurate mass (HRAM) mass spectrometry (MS) and inductively coupled mass spectrometry (ICP-MS), was developed for the analysis of low molecular weight iron (Fe) complexes, called ‘siderophores'. The complexity of the samples, their low concentrations, and the lability of the iron complexe were challenges in the development of methods for their identification and quantification. For the sample clean-up, solid phase extraction (SPE) using acidic conditions was developed to purify the samples, followed by evaporation to dryness. The individual 56Fe-siderophore complexes were identified by fast size-exclusion chromatography (FastSEC) - Orbitrap MSn based on the exact molecular mass (+ 1 ppm) and MS2. Their capability of exchanging the natural 56Fe with the spiked 58Fe was demonstrated by SEC with ICP-MS and ESI-MS detection. The method was applied to the analysis of peat collected in the Eastern part of the French Pyrenean mountains. Nineteen siderophores belonging to four different classes were presumptively identified and quantified. The results were compared with ICP-MS detection of iron and matching of the sum of the moles of iron complexes determined by the isotopic- ESI-MS within each peak as eluted from the fastSEC column.In the second part, a method using inductively coupled plasma mass spectrometry in the single particle mode and the conventional mode coupled to a flow field flow fractionation was developed to select suitable conditions for the synthesis of Ag-Au bimetallic nanoparticles and to monitor the colorimetric changes due to aggregations. Ag-Au BNPs, synthesized by using citrate reduction of Ag and Au ions, were used as sensors for the detection of Co2+. To better understand the colorimetric sensing of Co2+ using the Ag-Au BNPs, various mixtures were studied, viz. (i) only Ag-Au BNPs; (ii) Ag-Au BNPs with thiosulfate; (iii) Ag-Au BNPs with thiosulfate and ethylenediamine; and (iv) Ag-Au BNPs with thiosulfate, Co2+ and ethylenediamine. SP-ICP-MS was used to determine the core size, size distribution, and number concentration, as well as the heterogeneity of the particles synthesized by using various citrate concentrations and metal ratios. Fl-FFF-ICP-MS was also used to observe the hydrodynamic size and the Ag: Au signal intensity ratio of the BNPs to support information obtained from the SP-ICP-MS. The combination of the proposed techniques has been applied to monitor the reaction during colorimetric sensing. Additional information from fractograms provided by Fl-FFF-ICP-MS was also useful for the understanding of the aggregation of BNPs arising from the [Co(II)(en)3]2+ complex surrounding the surface of the BNPs. Furthermore, when compared to colorimetric sensing, the limit of detection for Co2+ ion, using the BNPs and SP-ICP-MS, were 20-fold lower, decreasing from ppb to ppt levels
Chemnitzer, René. "Intercalation von Stickstoff und Wasserstoff in Sr2N sowie ortsabhängige Feststoffcharakterisierung mit Laserablation". Doctoral thesis, Technische Universität Dresden, 2005. https://tud.qucosa.de/id/qucosa%3A23808.
Texto completo da fonteGoitom, Asfaha Daniel. "Fundamental Studies on Direct Injection Nebulisers for Sample Introduction in ICP Spectrometry : Aerosol Properties, ICP Characteristics and Analytical Performance". Doctoral thesis, Umeå University, Chemistry, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-671.
Texto completo da fonteThe performance of different types of nebulisers: Vulkan direct injection nebuliser (Vulkan DIN), direct injection high efficiency nebuliser (DIHEN), microconcentric nebuliser coupled to cyclonic or double pass spray chamber (MCN-C or MCN-DP, respectively) was investigated and compared when used for sample introduction to ICP-MS or ICP-OES. With ICP-OES, in axial viewing mode, intensity distributions across the radius of the plasma (radial intensity profiles) were determined for different spectral lines with Esum 1.85-15.41 eV to determine fundamental plasma properties for various matrices using Vulkan DIN and MCN-C. The results showed that with the MCN-C the ionisation temperature (Tion) was about the same across the measured region of the plasma (±3.0 mm) whereas with the Vulkan DIN the Tion was significantly lower in the centre of the plasma. A large deviation from local thermodynamic equilibrium, as well as deteriorated stability, was observed for the plasma when using the Vulkan DIN.
With ICP-MS noise power spectra (NPS) were generated to identify sources of noise. NPS showed that the magnitude of white noise for the tested sample introduction systems decreased in the following order: Vulkan DIN > DIHEN > MCN-C > MCN-DP. This order follows the decrease of mean droplet size and span of the size distribution, indicating that the white noise is caused by spatial and temporal non-uniform desolvation and ionisation. Another source of noise arose from the peristaltic pump and the magnitude of pump interference noise decreased in the following order: DIHEN > MCN-C/DP > Vulkan DIN. Mains power interference noise and 1/f noise were lower for the direct injection nebulisers compared to the spray chamber systems. The contribution or effects of these noise components on relative standard deviations of steady-state ion-count rate and isotope ratio measurements is discussed in this thesis.
Aerosols generated by the Vulkan DIN and the DIHEN were also directly characterised using Particle Dynamic Analysis. The Vulkan DIN produced particles with a mean diameter of ~30 µm and a size distribution between 2-80 µm. With the DIHEN the corresponding values were ~11 µm and 1-40 µm, respectively, with a few particles at 55-78 µm. The mean velocity of particles from the Vulkan DIN was ~10 m s-1 and from the DIHEN ~18 m s-1. The lower velocity allows longer residence time counteracting the effects of the larger droplet size.
Managh, Amy J. "Single-cell tracking of therapeutic cells using Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry". Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/16723.
Texto completo da fontePopel, Aleksej. "The effect of radiation damage by fission fragments on the structural stability and dissolution of the UO2 fuel matrix". Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/265103.
Texto completo da fonteDien-HanChiang e 江典翰. "Characterization of SiO2 Nanoparticles in Aqueous Environmental Matrices using Size Exclusion Chromatography ICP-MS versus Single Particle-ICP-MS". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/xd52m4.
Texto completo da fonteChung-ShengWang e 王重勝. "Development of Size Exclusion Chromatography-ICP-MS and Single Particle-ICP-MS in the characterization of SiO2NPs in aqueous environments". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/ff6wv7.
Texto completo da fonteJohnson, Monique Erica. "Determination of Metallic Constituents in Environmental and Biological Materials". 2012. https://scholarworks.umass.edu/open_access_dissertations/648.
Texto completo da fonteKińska, Katarzyna. "Wpływ emisji platynowców na środowisko". Doctoral thesis, 2018. https://depotuw.ceon.pl/handle/item/2854.
Texto completo da fonteIntroduction of car catalysts for general use caused an increase in emissions of platinum group elements (PGEs) to the environment. The increased level of platinum, palladium and rhodium is observed, especially in the vicinity of main communication routes, but still, rarely exceeds 1 μg g-1. The aim of the doctoral thesis was to determine an impact which PGEs may have on the environment. To make that possible, it's necessary to develop procedures, guaranteeing both, determination of the total content of analytes at appropriate concentration levels, as well as monitoring the changes they undergo and identification of their chemical forms. In order to get the reliable results, particular attention should be paid to the proper way of sample preparation before analysis. The determination of trace amounts of platinum, rhodium or palladium in environmental samples is not a simple task. The complexity of the sample matrix and the low concentration level of analytes cause that the determination methods must have sufficiently low limits of quantification. Often an additional step of analytes pre-concentration and separation from the matrix is introduced in the analytical procedure. As a part of the conducted research, the digestion procedures of soil and quartz sands samples, using the mixture of HNO3 and HCl acids, were optimized. Based on the results obtained for certified reference material (BCR-723; road dust) the possibility of efficient analytes transfers into the solution was proven. To isolate analytes from the matrix the solid phase extraction method was suggested. During the experiments, cation and anion exchange sorbents, as well as the eluents of various elution strength were used: 0.10 mol L-1 thiourea in 0.10 mol L-1 HCl, 2.0 mol L-1 HCl, 0.025-0.053 mol L-1 ammonium buffer. Developed sample preparation procedures were used to monitor PGEs in soil and quartz sands samples received from the monitoring plots distributed along high-ways and exposed to traffic-related contamination. Particular attention was paid to the possibility of using adsorptive stripping voltammetry (AdSV), which, due to low limits of quantification, can be an alternative method to inductively coupled plasma mass spectrometry (ICP MS). Based on the results obtained, the influence of road traffic on the increasing environmental pollution was proven, along with the indication of car catalysts as main emitters of the platinum group elements. The deposition of PGEs in soils makes that they can be taken up and accumulated by plants, which may cause disturbances in their proper functioning. The influence of platinum, palladium and rhodium on the growth of white mustard (Sinapis alba L.) was defined based on the plant material obtained from hydroponic cultivation. The plants, exposed to stress from the presence of various salts and nanoparticles of PGEs, have been characterized for the total content of metals taken from the nutrient solution and transported to aboveground organs (ICP MS), the presence of nanoparticles in selected tissues (SP ICP MS, TEM) and the formation of complexes with ligands present or de novo synthesized in the plant. The phytochelatins (PC2, PC3 and PC4), formed in plant cells, were identified by high-performance liquid chromatography with fluorescence detection (HPLC FLD) and electrospray ionization mass spectrometry (ESI MS). Additionally, thanks to the use of the SEC ICP MS method, some palladium compounds formed in Sinapis alba L. cells were detected and separated. The application of HILIC ESI MS method enabled identification of several Pd complexes with organic ligands, like histidine and nicotianamine, responsible for metal detoxification processes.
Kallistová, Anna. "Krystalochemie pyroxenů a amfibolů z Českého středohoří". Master's thesis, 2010. http://www.nusl.cz/ntk/nusl-296184.
Texto completo da fonte