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1

Lui, Kwok-on, and 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.

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2

Givelet, 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.

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Анотація:
Les travaux de thèse portent sur le développement de méthodes pour la caractérisation des nanoparticules (NPs) de dioxyde de titane (TiO2) dans les aliments. L’étude a été séparée distinctement en deux axes. Le développement de la méthode AF4-ICP-MS (I) au sein de la Plateforme Nano-Sécurité du CEA de Grenoble et le développement de la méthode Sp-ICP-MS (II) au sein du Laboratoire de la Sécurité Aliments de l’Anses à Maisons-Alfort.Pour le premier axe, les interactions électrostatiques entre les particules et la membrane de l’AF4 ont été étudiées. La charge de surface (potentiel zêta) a été mesuré pour différentes type de particule et membrane en fonction de plusieurs paramètres du solvant tel que le pH, la force ionique ainsi que la présence de tensio-actifs. Suite aux nombreuses analyses effectuées plusieurs conditions de solvant ont été identifiées comme favorable à la répulsion électrostatique entre les particules et la membrane ce qui permettrai de diminuer les pertes de particules au niveau de la membrane. Plusieurs conditions ont donc été testées directement pour l’analyse de NPs de TiO2 en AF4-ICP-MS. Il a ainsi été montré que les conditions favorisant les répulsions électrostatiques permettaient d’améliorer le taux dé récupération des particules au niveau du système AF4. Cependant les analyses ont aussi montré que les NPs de TiO2 n’étaient pas suffisamment dispersées pour pouvoir obtenir une distribution en taille fiable.Le second volet de la thèse, a eu pour but, dans un premier temps, d’optimiser le traitement de données de la méthode Sp-ICP-MS. Plusieurs améliorations ont été réalisées comme le calcul automatique du seuil bruit de fond-particule, le calcul de l'efficacité de transport où encore l'ajout de paramètres de contrôle qualité. Ce traitement de données a ensuite été comparée à un logiciel dédié aux analyses par Sp-ICP-MS et a permis de mettre en avant que la feuille de calcul interne donne des résultats avec une meilleure justesse, tout en fournissant des paramètres supplémentaires.Dans un second temps une optimisation de la méthode Sp-ICP-MS a été réalisée. Plusieurs paramètres ont donc été évalués comme le choix de l’isotope de titane, le temps d’acquisition, le type de solvant pour disperser les particules, ainsi que le mode de prélèvement de l’échantillon et son débit.Enfin, plusieurs aliments ont été analysés après avoir mis en place un protocole d’extraction des NPs. Les résultats obtenus ont permis de déterminer une distribution en taille des NPs de TiO2 présentes dans les échantillons
The 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
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3

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.

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4

Craig, 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.

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Анотація:
The determination of the isotopic composition of single uranium oxide particles, size 0.3-2 μm, for nuclear safeguards is current performed by either thermal ionisation mass spectrometry (TIMS) or Secondary Ion Mass Spectrometry (SIMS). Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS), a well-established analytical technique for determining the isotopic composition of solid materials, has the potential to be another method by which single uranium oxide particles can be analysed, complementing established protocol, but requires optimisation. In this study the ability of LA-ICP-MS to determine the isotopic composition, principally 234U/238U, 235U/238U and 236U/238U, of glass reference materials and sub-micron uranium oxide particles is investigated. To achieve the best detection efficiency a prototype high-speed ablation cell and injector design, designed previously at Loughborough University, was coupled to a high efficiency multi collector (MC-) ICP-MS. As a result an increase in signal-to-noise ratio and a measured detection efficiency of 5-7% was achieved for a LA-MC-ICP-MS system. The capability of the LA-MC-ICP-MS system, for the determination of the uranium isotopic composition of single particles was compared to a more established low-volume ablation cell. A source of additional uncertainty, blind time arising from incompatibilities with the mixed detector array of the MC-ICP-MS was identified. The impact of the additional uncertainty on isotope ratio analysis was modeled and a method developed to filter out affected data. LA-ICP-MS and LA-MC-ICP-MS were used to successfully determine the uranium isotopic compositions of sub-micron uranium oxide particles, of a known certified composition. A sample planchet containing particles of two distinct isotopic compositions was resolved. The utility of three data evaluation strategies to determine the isotopic composition of single uranium oxide particles was investigated. The necessity and advantages of calculating isotope ratios using the geometric mean is demonstrated, which has application for isotope ratio analysis performed on all forms of mass spectrometry. A novel approach to prepare particulate samples for laser ablation analysis, cytocentrifugation, is described. By using as the solvent, a mixture of nail polish and acetone, dispersed particles are held in a strong film layer thin enough to allow embedded particles to be imaged by SEM-EDX. A sample of uranium oxide particles in an environmental matrix prepared using cytocentrifugation is analysed by LA-MC-ICP-MS and their isotopic composition resolved.
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5

Schmidt, 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.

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Анотація:
In dieser Doktorarbeit wurde eine analytische Methode zur Charakterisierung metallischer Nanopartikel (NPs) entwickelt und die Methode bei der Untersuchung natürlicher Proben angewendet. Mit einem analytisches System bestehend aus einem Mikrotropfengenerator (microdroplet generator, MDG) zusammen mit einem pneumatischen Zerstäuber und einem induktiv gekoppeltem Plasma-Massenspektrometer (ICP-MS) konnte eine quantitative und qualitative Charakterisierung von NPs durchgeführt werden. Der MDG wurde verwendet um die Kalibrierungsfunktion für die massenspektrometrische Quantifizierung der Metalle in den Nanopartikelproben, die über den pneumatischen Zerstäuber eingeführt wurden, einzurichten. Der Hauptvorteil dieser Anordnung besteht darin, dass mit dem MDG für jedes Metall Tropfen einer gewünschten Größe hergestellt werden können und eine 100 %-ige Transporteffizienz gegeben ist. Die eingeführte Masse korrelierte mit der Signalintensität von Nanopartikeln, so dass die mit dem MDG generierten Tropfen für die Kalibrierung verwendet werden konnten ohne dass Referenzmaterial erforderlich war. Die aufwändige und fehleranfällige Bestimmung der Effizienz eines Zerstäubers, die für die Bestimmung des Metallgehaltes von NPs mittels eines Einzelpartikel-ICP-MS (spICP-MS) erforderlich ist, konnte dadurch vermieden werden. Unter Anwendung dieser dualen Einführungsmethode wurden Größen und Konzentrationen einer Reihe von Standard Silber (Ag) NPs und Referenz Gold (Au) NPs mit hoher Genauigkeit bestimmt. Zusätzlich wurde mit einem neuen kommerziell verfügbaren ICP-Flugzeitmassenspektrometer (ICP-TOF-MS) Ag und Au NPs in unterschiedlichen Matrices charakterisiert: in verschiedenen Salzsäure (HCl)- und Salpetersäure (HNO3)- Konzentrationen und in Gegenwart verschiedener Elemente. Bei den unterschiedlichen Matrices war die Größenbestimmung innerhalb der gegebenen Standardabweichungen korrekt.
In 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.
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6

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.

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Im Rahmen dieser Arbeit wurden vier verschiedene Methoden zur Separation, Identifikation sowie Quantifizierung von Silber-Nanopartikeln (Ag-NP) entwickelt. Mittels asymmetrischer Fluss-Feldflussfraktionierung (AF4) in Kombination mit einem induktiv gekoppelten Plasma-Massenspektrometer (ICP-MS) konnten eine gute Trennung und hohe Wiederfindungsraten gefunden werden. Eine systematische Studie möglicher Probenverluste während der Methodenoptimierung zeigte, dass der größte Verlust durch die Ag+-Ionen verursacht wurde, während Verluste durch Ablagerungen auf der Membran vernachlässigbar waren. Für Citrat-stabilisierte Ag-NP konnten mittels Hohlfaser-Fluss-Feldflussfraktionierung (HF5) gute Trennergebnisse erreicht und der hydrodynamische Durchmesser bestimmt werden. Zur Bestimmung der Partikelanzahlgrößenverteilung und des geometrischen Durchmessers von Partikeln in unbekannter Matrix wurde die Isotopenverdünnungsanalyse (IVA) erfolgreich mit der Einzelpartikel ICP-MS kombiniert. Weiterhin wurde eine Hochdruckflüssigkeitschromatographie(HPLC)-IVA-ICP-MS-Methode entwickelt, mit welcher NP und ihre korrespondierenden Ionen getrennt und quantifiziert werden konnten. Ein Vergleich der Ansätze zeigt, dass eine Kombination mehrerer Methoden nötig ist, um alle relevanten Informationen über die NP zu erhalten. Zum Abschluss wurde mit den entwickelten Methoden das Umweltverhalten der Ag-NP in einer Huminsäure(HS)-Suspension untersucht. Hierbei wurden erste Stabilisierungseffekte in Bezug auf die Ag-Konzentration und Partikelanzahl festgestellt. Zudem konnte mittels HF5 und HPLC für kleine NP in HA eine Modifikation in Form der Ausbildung eines zweiten, kleineren NP-Signals beobachtet werden.
In 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.
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7

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.

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Le projet de thèse NanoTi-Food vise principalement à améliorer la fiabilité de la caractérisation des nanoparticules de TiO2 (NPs) et à acquérir des connaissances sur l'additif alimentaire E171 y compris la migration de ces NP à partir des emballages alimentaires. Dans la première partie de l'étude (à réaliser à Anses), une nouvelle approche pour la caractérisation des NP de TiO2 sera développée et optimisée en utilisant l'approche « single particle » en combinaison avec la spectrométrie de masse à plasma à couplage inductif triple quadripôle (Sp-ICP- QQQMS). À cette fin, les paramètres analytiques les plus critiques, tels que les méthodes de calcul de l'efficacité du transport (TE) et le système d'introduction des échantillons seront évalués dans différentes conditions de travail (par exemple gaz de réaction, choix de l'isotope). Dans ce dernier cas, deux systèmes d'introduction d'échantillons à haut rendement (type APEX) seront comparés. Par ailleurs, une approche Sp complémentaire basée sur la MS-ICP haute résolution (Sp-ICP-HR MS) sera développée au LNE. La nouveauté dans ce cas sera l'utilisation d'un ICP-MS à haute résolution (champ de secteur magnétique) pour la détection, qui est la technique de pointe pour la détermination des éléments traces métalliques fortement interférés tels que le Ti. Un système d'injection interne sera également optimisé pour augmenter l'efficacité et la sensibilité du transport de l'échantillon. La validation de la méthode sera réalisée par comparaison inter-laboratoires entre le LNE et l'Anses. Une véritable valeur ajoutée du projet sera l'évaluation de l'incertitude de mesure liée à la caractérisation des NP de TiO2 par les deux approches Sp-ICP-MS (QQQ et HR). Les calculs d'incertitude prendront en compte non seulement la reproductibilité expérimentale et les incertitudes de chacune des variables nécessaires pour convertir le signal ICP-MS en taille et concentration de NPs, mais aussi et pour la première fois, l'effet du choix du seuil pour discriminer le signal ionique ICP-MS de celui des NP. L'effet des écarts par rapport à la forme sphérique sur les tailles sera également étudié et comparé à la microscopie électronique à balayage (MEB), qui est la méthode de référence pour la caractérisation des NP. Le projet vise également la préparation et la caractérisation exhaustive d'un matériau de référence réel (additif alimentaire) contenant des nanoparticules de TiO2. Une étude de faisabilité du développement d'une MR à base de E171 sous forme de suspension sera réalisée. À cette fin, un échantillon E171 représentatif sera préparé et entièrement caractérisé par un panel de techniques complémentaires, telles que SEM, Sp-ICP-QQQMS, Sp-ICP-HR MS, diffraction des rayons X (XRD) pour évaluer avec précision les principaux paramètres d'intérêt, tels que le diamètre médian et moyen, la distribution de taille, la fraction de nanoparticules, les impuretés chimiques et la fraction cristallographique. Enfin, les deux approches analytiques développées à l'Anses et au LNE, dont la méthode développée pour l'évaluation de l'incertitude globale, seront appliquées à l'étude du transfert des NP de TiO2 à partir des emballages alimentaires. Tout au long du projet, les données de taille obtenues en utilisant les nouvelles approches basées sur l'approche « single particle » pour la caractérisation des NP de TiO2 seront comparées aux mesures SEM, qui est la méthode de référence pour la taille dans ce domaine d'étude. Les études sur la migration des emballages alimentaires sont en effet une étude de cas sélectionnée où la Sp-ICP-MS a le potentiel de fournir des informations supplémentaires par rapport à d'autres paramètres tels que la concentration de particules, la proportion de particules par rapport à la forme dissoute, qui sont également importantes pour la migration qui est important afin d'améliorer les études d'évaluation des risques
This 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
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8

Chan, Ka-lok, and 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.

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9

Löhr, 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.

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Анотація:
Induktiv gekoppelte Plasma-Massenspektrometrie mit Laserablation (LA-ICP-MS) wird zunehmend für die Einzelzellanalyse eingesetzt, jedoch wird eine weitere verbreitete Verbreitung durch den geringen Durchsatz behindert. Daher wurde in dieser Arbeit der Durchsatz von Einzelzellen-LA-ICP-MS untersucht und verbessert. Zunächst werden die beiden möglichen Ablationsmodi, Bildgebung und Einzelpunktanalyse (SSA), hinsichtlich ihrer analytischen Gütezahlen (Signal-Rausch-Verhältnis, Präzision, Genauigkeit, Durchsatz) verglichen. Hierfür wurden adhärente 3T3-Fibroblastenzellen mit zwei Metallfarbstoffen angefärbt und mit beiden Methoden mehrere Dutzend Zellen vermessen. SSA zeigte überlegene Eigenschaften hinsichtlich Durchsatz und Nachweisgrenzen. Darüber hinaus wurde gezeigt, dass >400 Zellen analysiert werden müssen, um zufriedenstellende Statistiken für einen quantitativen Vergleich der Ergebnisse zu erhalten, was als zu mühsam befunden wurde. Daher wurde ein Einzelzellen-Arraying-Schritt integriert, um eine automatisierte LA-ICP-MS-Analyse zu ermöglichen. Hierfür wurden zwei Arrayingverfahren getestet: Zunächst wurde das mikrofluidische Arraying von Zellen getestet, jedoch verhinderte das Einklemmen von weichen PDMS-Chips eine erfolgreiche Anwendung, und eine Neugestaltung des Chips wäre erforderlich. Daraufhin wurde eine neuartige Technologie getestet, die auf dem Arraying von Tröpfchen in Verbindung mit der Bilderkennung von Zellen beruht, wobei ein Anordnungsdurchsatz von 550 Zellen pro Stunde und eine beispiellose Einzelzellengenauigkeit (> 99%) gefunden wurde. In einem Proof-of-Principle-Experiment wurde ein Zellarray von THP-1-Suspensionszellen mittels LA-ICP-TOF-MS analysiert und erstmals gleichzeitig endogene und exogene Isotope einzelner Zellen als Isotopen-Fingerabdrücke von Zellen mit Nachweisgrenzen von lediglich wenigen hundert attogramm. Schließlich wurden diese Ergebnisse mit der derzeit gebräuchlichsten Analysemethode Single-Cell (sc)-ICP-MS verglichen.
Laser 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.
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10

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.

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11

Löhr, Konrad [Verfasser], Michael [Gutachter] Linscheid, and 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.

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12

Kerr, 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.

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The application of ICP-MS to the fields of proteomics and genomics has arisen in part due to its ability to detect and quantify trace levels of S and P, which are major constituents in proteins and nucleic acids respectively. The development of collision/reaction cell technology and high resolution instruments has enabled these biologically important elements to be measured and quantified at the pg - ng ml-1 level. Despite these advances, the detection limits of P and S are still inferior compared to other elements. Oligonucleotides containing biotin functionality were labelled with Au nano-particles attached to a streptavidin protein to achieve site specific labelling, with 100% labelling efficiency. Each nano-particle contained ~86 Au atoms, resulting in an 882 fold signal enhancement for 24 base length oligonucleotides. However, this enhancement factor was only observed when one oligonucleotide bound to one nano-particle in a 1:1 ratio. Much lower Au labelling efficiencies and signal enhancements were observed when thiolated oligonucleotides were labelled with maleimide functionalised gold nano-particles. This was attributed to the extensive and difficult sample preparation steps that were required prior to labelling. The detection and quantification of adducts formed between DNA and the Pt anti-cancer drugs cisplatin and oxaliplatin were also investigated with ICP-MS. Acid digestion of the carbon based DNA matrix enabled Pt adducts to be quantified at low dose rates of 1 Pt atom per 1 500 000 nucleotides in ~12 μg DNA. Such sensitive mass spectrometric determinations could be employed in clinical tests to detect and quantify low level adducts formed in patients in-vivo. To complement ICP-MS analysis, electrospray ionisation linear ion trap mass spectrometry was employed to study the interaction of oxaliplatin with the four DNA nucleobases. Multiple stage mass spectrometry enabled detailed Pt-nucleobase adduct fragmentation pathways to be established. The method of DNA detection using P in conjunction with the collision cell, or cool plasma to form PO+ was also demonstrated and the limitations of the method, namely, polyatomic interferences and severe matrix effects were highlighted.
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13

Chemnitzer, 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.

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Die Strukturen der Erdalkalimetall-Subnitride (EA2N) von Calcium, Strontium und Barium ermöglichen mit ihrem schichtartigen Aufbau aus EA6N-Oktaedern Intercalationsreaktionen. Die Redox-Intercalation von Stickstoff in Sr2N wurde an Einkristallen untersucht. Nur durch eine drastische Erhöhung des Reaktionsgasdruckes im Vergleich zu den Reaktionen an mikrokristallinen Proben wurde die Intercalation der Diazenidionen in die Kristalle zu Sr4N3 und SrN möglich. Für eine analoge Intercalation von Wasserstoff in Sr2N konnten die Reaktionsbedingungen dahingehend optimiert werden, dass erstmals phasenreines Strontiumnitridhydrid (Sr2N)H bzw. deuterid (Sr2N)D erhalten wurde. Anhand von Intercalationsreaktionen mit Sr2N Kristallen konnte gezeigt werden, dass der Intercalationsprozess, erkennbar an der deutlichen Farbänderung von schwarz nach bersteinfarben, von außen nach innen fortschreitet. Als Methode zur räumlich aufgelösten Analyse wurde die Laserablation, in Kombination mit einem ICP - Massenspektrometer (LA-ICP-MS) verwendet. In der Literatur beschriebene Quantifizierungsstrategien wurden auf die Anwendbarkeit für die gegebene Fragestellung untersucht. Mit der ortsaufgelösten Analyse von Einkristallen konnte gezeigt werden, dass die Intercalation von Stickstoff in die Kristalle kontinuierlich von den Kanten zur Kristallmitte fortschreitet.
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14

Maknun, 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.

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L'objectif principal de cette recherche est le développement de méthodes analytiques utilisant une technique de séparation couplée à la spectrométrie de masse pour l'analyse de complexes de fer de faible poids moléculaire et une technique de single-particle ICP MS pour la détection de nanoparticules bimétalliques.Dans la première partie, une méthode utilisant la chromatographie liquide avec spectrométrie de masse à double détecteur, spectrométrie de masse (MS) à haute résolution par électrospray (HRAM) et spectrométrie de masse à couplage inductif (ICPMS), a été développée pour les complexes du fer (Fe) de faible poids moléculaire, appelés 'sideophore', dans un échantillon d'un sol. La complexité des échantillons étudiés, les faibles concentrations et la labilité des analytes ont posé un défi dans le développement de méthodes pour leur identification et leur quantification. Pour éliminer la matrice, une extraction en phase solide (SPE) a été développée dans des conditions acides pour purifier la majeure partie des complexes 56Fe-sidérophore et concentrée par évaporation. Les complexes 56Fe-sidérophore ont été identifiés par chromatographie d'exclusion stérique rapide (FastSEC) - Orbitrap MSn sur la base de la masse moléculaire exacte (+ 1 ppm) et de la fragmentation MS2 ou MS3. Leur capacité à échanger facilement le 56Fe naturel contre le 58Fe ajouté a été démontrée par SEC avec détection par l'ICP MS et l'ESI MS. La méthode a été appliquée à l'analyse de tourbe prélevée dans la partie orientale des montagnes pyrénéennes françaises. Dix-neuf sidérophores appartenant à quatre classes différentes ont été identifiés et quantifiés sans avoir besoin d'un standard authentique. Les résultats ont été validés à l'aide de la détection ICP MS du fer en comparant la somme des complexes de fer déterminés par échange isotopique - ESI MS dans chaque pic observé par FastSEC-ICP MS.Dans la deuxième partie du manuscrit, une méthode utilisant la spectrométrie de masse à plasma à couplage inductif -ICP-MS en mode particule unique (SP-ICP-MS) et en mode conventionnel couplée au fractionnement d'écoulement de champ (FlFFF) a été développée. Les conditions de synthèse de nanoparticules bimétalliques (BNP) Ag-Au ont été optimisées pour appliquer celles-ci à la détection colorimétrique basée sur le concept d'agrégation. Les BNP Ag-Au, synthétisés par la réduction par le citrate des ions Ag et Au, ont été utilisées comme capteurs pour la détection du Co2+. Pour mieux comprendre la détection colorimétrique du Co2+ à l'aide de BNP Ag-Au, divers mélanges de solutions ont été étudiés, notamment : (i) uniquement des BNP Ag-Au ; (ii) BNP Ag-Au avec thiosulfate; (iii) BNP Ag-Au avec thiosulfate et éthylènediamine; et (iv) Ag-Au BNPs avec thiosulfate, Co2+ et éthylènediamine. SP-ICP-MS a été utilisé pour déterminer la taille du noyau, la distribution de taille et la concentration en nombre de particules, ainsi que l'hétérogénéité des particules synthétisées en utilisant diverses concentrations de citrate et un rapport de métal. FlFFF-ICP-MS a également été utilisé pour observer la taille hydrodynamique et le rapport d'intensité du signal de Ag et Au dans les BNP et donc pour étayer les informations obtenues à partir de SP-ICP-MS. La combinaison des techniques proposées dans des conditions appropriées a permis de surveiller la réaction de détection colorimétrique. Les informations supplémentaires du fractogramme fournies par FlFFF-ICP-MS ont également été utiles pour comprendre l'agrégation des BNP due au complexe [Co(II)(en)3]2+ autour de la surface des BNP. En outre, par rapport à la détection colorimétrique classique, la limite de détection (LOD) pour la détection des ions Co2+ a été réduite de 20 fois, du niveau ppb au niveau ppt
The 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
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15

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.

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Анотація:
Die Strukturen der Erdalkalimetall-Subnitride (EA2N) von Calcium, Strontium und Barium ermöglichen mit ihrem schichtartigen Aufbau aus EA6N-Oktaedern Intercalationsreaktionen. Die Redox-Intercalation von Stickstoff in Sr2N wurde an Einkristallen untersucht. Nur durch eine drastische Erhöhung des Reaktionsgasdruckes im Vergleich zu den Reaktionen an mikrokristallinen Proben wurde die Intercalation der Diazenidionen in die Kristalle zu Sr4N3 und SrN möglich. Für eine analoge Intercalation von Wasserstoff in Sr2N konnten die Reaktionsbedingungen dahingehend optimiert werden, dass erstmals phasenreines Strontiumnitridhydrid (Sr2N)H bzw. deuterid (Sr2N)D erhalten wurde. Anhand von Intercalationsreaktionen mit Sr2N Kristallen konnte gezeigt werden, dass der Intercalationsprozess, erkennbar an der deutlichen Farbänderung von schwarz nach bersteinfarben, von außen nach innen fortschreitet. Als Methode zur räumlich aufgelösten Analyse wurde die Laserablation, in Kombination mit einem ICP - Massenspektrometer (LA-ICP-MS) verwendet. In der Literatur beschriebene Quantifizierungsstrategien wurden auf die Anwendbarkeit für die gegebene Fragestellung untersucht. Mit der ortsaufgelösten Analyse von Einkristallen konnte gezeigt werden, dass die Intercalation von Stickstoff in die Kristalle kontinuierlich von den Kanten zur Kristallmitte fortschreitet.
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16

Goitom, 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.

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The 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.

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17

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.

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Cellular therapy is emerging as a clinically viable strategy in the field of solid organ transplantation, where it is expected to reduce the dependency on conventional immunosuppression. This has produced a demand for highly sensitive methods to monitor the persistence and tissue distribution of administered cells in vivo. However, tracking cells presents significant challenges. In many cases transplanted cells are autologous with the immune system of the transplant recipient, and hence are invisible to typical methods of detection. To enable their differentiation, the cells must be labelled with a suitable, non-toxic and long lifetime label, prior to their administration to patients. In addition, administered cells represent only a small fraction of the recipient's endogenous cells, which necessitates the use of an extremely sensitive detection method. Laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS) is an exquisitely sensitive analytical technique, capable of imaging trace elements in complex samples, at high spatial resolution.
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18

Popel, 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.

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The aim of this work was to study the separate effect of fission fragment damage on the structural integrity and matrix dissolution of uranium dioxide in water. Radiation damage similar to fission damage was created by irradiating bulk undoped and doped ‘SIMFUEL’ disks of UO2, undoped bulk CeO2 and thin films of UO2 and CeO2 with high energy Xe and U ions. The UO2 thin films, with thicknesses in the range of 90 – 150 nm, were deposited onto (001), (110) and (111) orientations of single crystal LSAT (Al10La3O51Sr14Ta7) and YSZ (Yttria-Stabilised Zirconia) substrates. The CeO2 thin films were deposited onto single crystal silicon (001) substrates. Part of the bulk UO2 and CeO2 samples, the thin films of UO2 on the LSAT substrates and the thin films of CeO2 were irradiated with 92 MeV 129Xe23+ ions to a fluence of 4.8 × 1015 ions/cm2 to simulate the damage produced by fission fragments in uranium dioxide nuclear fuel. Part of the bulk UO2 and CeO2 samples and the thin films of UO2 on the YSZ substrates were irradiated with 110 MeV 238U31+ ions to a fluence of 5 × 1010, 5 × 1011 and 5 × 1012 ions/cm2 to study the accumulation of the damage induced. The irradiated and unirradiated samples were studied using scanning electron microscopy (SEM), focused ion beam (FIB), atomic force microscopy (AFM), energy dispersive X-ray (EDX) spectroscopy, electron probe microanalysis (EPMA), X-ray diffraction (XRD), electron backscatter diffraction (EBSD), secondary ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS) techniques to characterise the as-produced samples and assess the effects of the ion irradiations. Dissolution experiments were conducted to assess the effect of the Xe ion irradiation on the dissolution of the thin film UO2 samples on the LSAT substrates and the bulk and thin film CeO2 samples. The solutions obtained from the leaching of the irradiated and unirradiated samples were analysed using inductively coupled plasma mass spectrometry (ICP-MS). XRD studies of the bulk UO2 samples showed that the ion irradiations resulted in an increased lattice parameter, microstrain and decreased crystallite size, as expected. The irradiated UO2 thin films on the LSAT substrates underwent significant microstructural and crystallographic rearrangements. It was shown that by irradiating thin films of UO2 with high energy, high fluence ions, it is possible to produce a structure that is similar to a thin slice through the high burn-up structure. It is expected that the ion irradiation induced chemical mixing of the UO2 films with the substrate elements (La, Sr, Al, Ta). As a result, a material similar to a doped SIMFUEL with induced radiation damage was produced.
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19

Dien-HanChiang and 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.

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20

Chung-ShengWang and 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.

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21

Johnson, Monique Erica. "Determination of Metallic Constituents in Environmental and Biological Materials." 2012. https://scholarworks.umass.edu/open_access_dissertations/648.

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Studies of the interaction of the relevant metal, metalloid or nanoparticulate species with biological systems are underpinned by the provision of reliable information about chemical composition of the relevant materials. Often, no methods of chemical analysis are available. The work described in this dissertation centers on developing methods to help with studies for a variety of analytes and samples. A method was developed for the determination of 11 trace elements (As, Cd, Co, Cr, Cu, Fe, Mg, Mn, Pb, Ti, and Zn) in human breast milk and infant formulas by inductively coupled plasma optical emission spectrometry (ICP-OES) following microwave-assisted digestion. A method was established for the determination of trace elements, with an emphasis on titanium as titanium dioxide, in snack foods and consumer products. The interactions of some dissolved metals, including rare earth elements, and metallo-nanoparticles (silver, gold, titanium dioxide, aluminum oxide, and iron) with aquatic plants were studied. After exposure in a variety of mesocosms, the partitioning of the elemental species between various compartments was quantified by ICP-MS and ICP-OES following microwave-assisted digestion. An ICP mass spectrometry (MS) method has also been developed to quantify the uptake of gold and silver nanoparticles by C. elegans. Uptake of gold nanoparticles was size dependent, suggesting increased ingestion efficiency with increased particle diameter. The feasibility of discriminating between suspended TiO2 nanoparticles and dissolved titanium by the analysis of the rapid transient signal events obtained from the ICP-MS instrument operated in a rapid response mode was also developed. Data handling parameters were established that allowed a distinction in the signals for nanoparticulate and standard solutions. Spikes in the signal were defined by distinct parameters using the mean and standard deviation, where a spike in the signal was defined as a signal > + ks (k =3). This approach however did lead to a statistical difference in the spike signal events for solutions and nanosuspensions.
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22

Kińska, Katarzyna. "Wpływ emisji platynowców na środowisko." Doctoral thesis, 2018. https://depotuw.ceon.pl/handle/item/2854.

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Анотація:
Wprowadzenie do powszechnego użytku katalizatorów samochodowych spowodowało wzrost emisji metali z grupy platynowców (PGE) do środowiska. Podwyższony poziom zawartości platyny, palladu i rodu jest obserwowany szczególnie w okolicach dużych szlaków komunikacyjnych, rzadko jednak przekracza 1 μg g-1. Celem pracy doktorskiej było określenie wpływu, jaki pierwiastki z tej grupy wywierają na środowisko. Aby to było możliwe konieczne jest dysponowanie metodami gwarantującymi zarówno oznaczanie całkowitych zawartości analitów na odpowiednich poziomach stężeń, jak i śledzenie przemian jakim ulegają i identyfikację ich form chemicznych. Aby uzyskane wyniki oznaczeń były wiarygodne należy szczególną uwagę zwrócić na sposób przygotowania badanych materiałów do analizy. Pod względem analitycznym, oznaczanie śladowych ilości platyny, rodu czy palladu w próbkach środowiskowych nie jest zadaniem prostym. Złożoność matrycy próbek oraz niski poziom stężeń sprawiają, że metody oznaczeń muszą charakteryzować się odpowiednio niskimi granicami oznaczalności. Często w procedurze analitycznej wprowadza się dodatkowy etap zatężania analitów i uproszczenia matrycy próbki. W ramach prowadzonych badań zoptymalizowano procedury roztwarzania próbek gleb i piasków kwarcowych z wykorzystaniem mieszaniny kwasów HNO3 i HCl. W oparciu o wyniki uzyskane dla certyfikowanego materiału odniesienia – pyłu drogowego BCR-723 wykazano efektywne przeprowadzenie PGE do roztworu. Do wydzielania analitów z matrycy wykorzystano metodę ekstrakcji do fazy stałej. W trakcie badań zastosowano sorbenty kationo- i anionowymienne oraz eluenty o różnej sile elucyjnej: 0,1 mol L-1 tiomocznik w 0,1 mol L-1 HCl, 2 mol L-1 HCl, 0,025-0,053 mol L-1 bufor amonowy. Opracowane procedury przygotowania próbek zastosowano do monitorowania PGE w próbkach gleb i piasków kwarcowych, pobieranych z poletek monitoringowych rozmieszczonych wzdłuż ciągów komunikacyjnych i eksponowanych na zanieczyszczenia związane z ruchem drogowym. Szczególną uwagę zwrócono na możliwość zastosowania w oznaczeniach metody woltamperometrii inwersyjnej z adsorpcyjnym zatężaniem (AdSV), która, ze względu na niskie granice oznaczalności może być alternatywą do metody spektrometrii mas z plazmą indukcyjnie sprzężoną (ICP MS). Na podstawie uzyskanych wyników wykazano wpływ ruchu drogowego na wzrastające skażenie środowiska oraz wskazano katalizatory samochodowe, jako główne emitery pierwiastków z grupy platynowców. Odkładanie się PGE w glebach sprawia, że mogą być one pobierane i akumulowane przez rośliny, co może powodować zaburzenia ich prawidłowego funkcjonowania. W oparciu o materiał roślinny pozyskany w ramach upraw hydroponicznych określono wpływ platyny, palladu i rodu na rozwój gorczycy białej (Sinapis alba L.). Rośliny narażone na stres związany z obecnością różnych soli i nanocząstek PGE zostały scharakteryzowane pod kątem całkowitej zawartości metali pobranych z pożywki i przetransportowanych do części nadziemnych (ICP MS), obecności nanocząstek w wybranych tkankach (SP ICP MS, TEM), jak i tworzenia kompleksów z ligandami obecnymi lub syntezowanymi de novo w roślinie. Powstałe w tkankach fitochelatyny (PC2, PC3 i PC4) zidentyfikowano metodą wysokosprawnej chromatografii cieczowej z detekcją fluorescencyjną (HPLC FLD) oraz spektrometrią mas z jonizacją przez elektrorozpraszanie (ESI MS). Dodatkowo dzięki wykorzystaniu metody SEC ICP MS, wykryto i rozdzielono grupy związków palladu powstających w komórkach Sinapis alba L. Z kolei zastosowanie metody HILIC ESI MS umożliwiło zidentyfikowanie wybranych połączeń Pd z ligandami organicznymi, jak histydyna i nikotianamina, odpowiedzialnymi za procesy detoksykacji metali.
Introduction 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.
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Kallistová, Anna. "Krystalochemie pyroxenů a amfibolů z Českého středohoří." Master's thesis, 2010. http://www.nusl.cz/ntk/nusl-296184.

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Анотація:
Contents of major, minor and trace elements in clinopyroxenes and clinoamphiboles of basanites, volcanoclastics, essexites, sodalitic syenites, and monzodiorites of the České středohoří Mts. has been determined using an electrone microprobe and LA-ICP-MS techniques. Composition of clinopyroxenes corresponds to either diopside or augite and clinoamphiboles can be classified as kaersutite or pargasite. Some pyroxenes display pronounced sector zoning showing increased contents of Mg and Si in pyramidal sectors whereas prismatic sectors show Fe, Ti and Al enrichment. Chemical composition of both sectors corresponds to diopside. Growth zoning has been found in the samples from basanites and volcanoclastics. Grain cores display the chemistry of augite and towards the rim the chemical composition changes to diopside. Samples have also been analyzed by powder and single crystal X-ray diffraction techniques. Samples of pyroxenes appear to be either pure or they contain negligible admixtures of phlogopite. Samples of amphiboles are also either without any admixtures or they show contamination by low amounts of diopside or augite, or phlogopite may rarely be encountered. Mutual relationship between the size of the unit cell parameters b and and substitutions in M1,2,3 and A sites has been observed. Longer mean T-O...
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