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Magnetic resonance imaging with multimodal T2 contrast agents based on fluorescence-labelled magnetic cores with the spinel structure
Kikerlová, Soňa ; Kaman, Ondřej (advisor) ; Nižňanský, Daniel (referee)
This diploma thesis was focused on the preparation of magnetic and fluorescently labelled spinel type nanoparticles, specifically nanoparticles of zinc-doped cobalt ferrite intended for application in magnetic resonance imaging and fluorescence microscopy in experimental practice. In previous studies, various ferrite nanoparticles exhibited relatively high transverse relaxation times and strong negative T2 contrast. These properties were also supposed for the zinc-doped cobalt ferrite nanoparticles. This assumption was confirmed by studying their magnetic and contrasting properties. Fluorescence properties of the prepared nanoparticles were also successfully studied. With respect to the intended applications of these particles, the issue of suitable surface modification of magnetic cores, their colloidal stabilization in an aqueous suspension and toxicity in biological systems were studied. Key words: nanoparticles, ferrites, MRI, relaxation
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Design and characterization of advanced polymer-coated upconversion nanoparticles
Kostiv, Uliana ; Horák, Daniel (advisor) ; Kaman, Ondřej (referee) ; Brožek, Jiří (referee)
Lanthanide-based upconversion nanoparticles are able to absorb low-energy near-infrared (NIR) photons and emit visible or ultraviolet light. This unique optical property enables luminescent detection without autofluorescence from biological samples that is crucial for bioimaging and diagnostics. Moreover, NIR irradiation allows to deliver light deep into the tissue, which can be used for drug or gene delivery and NIR-induced photodynamic therapy (PDT) of tumors. Despite huge effort during the last 10 years devoted to the upconversion nanoparticle synthesis and their surface engineering, preparation of the particles suitable for biomedical applications still remains a big challenge. The current work is focused on synthesis of the upconversion nanoparticles with controllable morphology, size, distribution, crystallinity, and high upconversion efficiency, as well as on desirable surface modification by biocompatible inorganic or organic polymers. Neat and functionalized homogeneous silica shell was introduced on the NaYF4:Yb3+ /Er3+ and NaGdF4:Yb3+ /Er3+ nanoparticles to enhance their biocompatibility and colloidal stability in water. To render the nanoparticles with targeting moieties, their surface was decorated with cell-adhesive RGD or cell-penetrating TAT peptides. The RGD- and TAT- conjugated...
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Evolutionary history of Parnassiinae
Kaman, Ondřej ; Čepička, Ivan (advisor) ; Král, David (referee)
This review is devoted to the evolutionary history of the Parnassiinae subfamily of the family Papilionidae and particularly to the nominate genus Parnassius which is the main group among the eight extant Parnassiinae genera. At first, the taxonomic concept, monophyly, and phylogenetic position of Parnassiinae are thoroughly discussed. It is shown that all its genera form three clades that are currently classified as tribes. Further, the estimated time of the divergence of Parnassiinae is given together with the description of all fossil taxa. The subsequent part is entirely focused on Parnassius whose internal phylogeny largely corroborates the traditional classification on eight subgenera, although the phylogenetic relationships among these clades remain mostly unresolved. All the clades are systematically discussed and interesting phylogenetic cases of species complexes and closely related taxa are analysed and supplemented by taxonomic remarks. The last three chapters are dedicated to the phylogeography of P. mnemosyne, P. apollo, and P. phoebus complex. Their evolutionary history is discussed in relation to glacial events in Pleistocene and warming of the climate in Holocene. The whole treatment attempts to integrate morphological, molecular, and biogeographical views together in order to provide a...
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Praparation, structure and properties of hybrid nanoparticles with perovskite and spinel type cores
Kaman, Ondřej ; Havlíček, David (advisor) ; Wágner, Tomáš (referee) ; Zbořil, Radek (referee)
Charles University in Prague Faculty of Science Department of Inorganic Chemistry and Academy of Sciences of the Czech Republic Institute of Physics Department of Magnetics and Superconductors ondřej Kuman Preparation, structure and properties of hybrid nanoparticles with perovskite and spinel type cores Summary oÍ Thesis Praha 2009 Introduction The presented work Preparation, stntcture- and properties of lrybrid nanoparticles withperovskite and spinel ýpe cores was primarily dedicated to the synit,esis *á .,uav of hybridmagnetic nanoparticles based on La1."Sr*Mnól perovskite phase as core material and silicashell. The motivatio^n for this topic is the chancó that the mentioned nanomaterials could beused as mediators for magnetically induced hyperthermia or at least they could show thedirection for future development of new agent inlended for magnetic hyperthermia. Moreover,it turned out that these nanoparticles are interesting as contrast agents for MRI and thereforethe sense of the intended work obtained anothei dimension. In order to achieve certaingenerality of the developed procedures. and- to _enable por.1t1" comparison oiu.q.ri." d. data,we have involved some aspects concerning the CoFezo+ andCot.*ZdF";ó;.pt"el phases. Aims of Thesis I' To study of po_ssible preparation of Lar-*sr*Mnol nanoparticles...
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