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Preparation and Characterization of Drug Carrier Systems on the Basis of Magnetic Nanoparticles
Chvátalová, Barbora ; Burdíková, Jana (referee) ; Kalina, Michal (advisor)
This bachelor thesis deals with the study of magnetic nanoparticles, optimizing their preparation and stabilization. The nanoparticles with different ratios of Fe2+ and Fe3+ ions were prepared by coprecipitation by variously concentrated sodium hydroxide. Three samples of particles were selected and were further observed. Their stability in Milli-Q water, buffer, polyvinylalcohol, hyaluronic acid and chitosan was studied in function of time using methods of dynamic and electrophoretic light scattering. By UV-VIS spectrometry it was confirmed that the magnetic nanoparticles were actually prepared. Nanoparticles coated with chitosan and hyaluronic acid were then further characterized using FT-IR, XRD and SEM.
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Optimisation of Isolation Procedure and Characterization of Amorphous PHB granules
Kratochvíl, Zdeněk ; Obruča, Stanislav (referee) ; Kalina, Michal (advisor)
First artificial PHB granules were prepared under the terms of this thesis. The effect of used PHB solvent, ultrasonic bath temperature and time, solvent evaporation temperature and stabilizing agent nature was investigated using dynamic and electrophoretic light scattering. The most proper parameters were demonstrated at samples which were prepared by dissolving of PHB in chloroform, stabilizing with CTAB or lecithin, ultrasonifying at 35 °C followed by chloroform evaporating at 60 °C. Based on ATR-FTIR and Raman spectroscopy results, it was found out that PHB within the artificial granules were in crystalline form. The native PHB granules were isolated from Cupriavidus necator using either lysosyme, deoxyribonuclease and cell disruption by ultrasonification or digestion with alcalase, SDS and EDTA. Granules obtained by both isolation procedures were characterized by ATR-FTIR, Raman spectroscopy, light scattering techniques and DSC. According to the analyses results, the second mentioned procedure turned out to be more effective for obtaining the polymer in amorphous state. Furthermore, the polymer within granules recovered by using this procedure was thermally more stable. Last but not least, the native PHB granules samples were exposed to effect of acetone, lipase and sodium hypochlorite, assuming that polymer crystallinity should be increased by these chemicals in varying degrees. The highest degree of crystallinity was achieved after their treatment with lipase.
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Numerical simulation of the laser light scattering from rough surfaces
Šulc, Václav ; Klapetek, Petr (referee) ; Ohlídal, Miloslav (advisor)
A Matlab numerical model for scattering simulation was proposed based on the solution derived from the Beckmann-Kirchhoff scalar theory of scattering of electromagnetic waves from rough surfaces. A series of various synthetic surface samples were obtained using the open source software Gwyddion on which numerical simulations of scattering were carried out. The validity of this numerical model was tested and compared with experimental results.
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Rendering of Underwater Scenes
Smutný, Martin ; Vlnas, Michal (referee) ; Milet, Tomáš (advisor)
Cílem této práce je vykreslení podvodních scén a světelných efektů typických pro takové scény interaktivně ve vysoké kvalitě. Práce se konkrétně zaměřuje na fyzikálně založené vykreslování oceanických vod, které mají komplexní a vysoce proměnlivé optické vlastnosti. Vykreslování takových prostředí vyžaduje simulaci simulaci rozptylu světla uvnitř vodního objemu. Byly důsledně prozkoumány relevantní metody pracující v reálném čase. Byla navrhnuta jednoduchá oceanická scéna, které se skládá z procedurálně generovaného terénu, vodního povrchu a atmosferického modelu. Byl navrhnut fyzikálně založený bio-optický model vodního objemu. Rozptyl prvního řádu je aproximován, tím, že jsou vykreslovány fyzikálně založené povrchové a volumetrické kaustiky, vznikající lomem světla skrze vodní povrch. Vícenásobný rozptyl je aproximován na základě vlastností takových vod. Navržené techniky byly implementovány. Scénu je možné vykreslit z pohledu nad i pod povrchem vody. Techniky vykreslují efekty vodního objemu v přijatelné kvalitě a interaktivity bylo dosaženo na GPU nižší třídy.
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Rendering of Underwater Scenes
Smutný, Martin ; Vlnas, Michal (referee) ; Milet, Tomáš (advisor)
Tato práce se zabývá vykreslováním realistických podvodních scén pomocí technik v reálném čase. Práce se zaměřuje na vykreslování oceanických vod, které mají komplexní a vysoce proměnlivé optické vlastnosti. Vykreslování takových prostředí je náročnou oblastí v počítačové grafice, která zahrnuje simulaci rozptylu světla uvnitř vodního objemu. Jsou zkoumány metody počítačové grafiky pracující v reálném čase pro vykreslování a simulaci oceánů. Jsou navrhnuty techniky aproximující rozptyl první řádu a vícenásobný rozptyl pro vykreslení vodního objemu za pomocí krokování paprsku. Optické vlastnosti objemu jsou popsány pomocí fyzikálně založeného bio-optického modelu. Navíc, jsou vykresleny povrchové a volumetrické kaustiky odpovídající lomu světla skrze simulovaný vodních povrch pomocí Fourierovy transformace. Navržená technika pro vykreslování scén nebyla implementována v plné podobě. Byly implementovány pouze některé navržené techniky a s nimi byly provedeny experimenty zvlášť.
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Association behavior of diblock copolymers with pH-responsive and thermoresponsive blocks in aqueous solutions
Škorňa, Adam ; Štěpánek, Miroslav (advisor) ; Raus, Vladimír (referee)
Univerzita Karlova Přírodovědecká fakulta Studijní program: Makromolekulární chemie Studijní obor: Makromolekulární chemie Bc. Adam Škorňa Asociační chování dvojblokových kopolymerů s pH-responsivními a termoresponsivními bloky ve vodných roztocích Associationbehavior of diblock copolymers with pH-responsive and thermoresponsive blocks in aqueous solutions Diplomová práce Školitel: prof. RNDr. Miroslav Štepánek. Ph.D. Praha 2022/2023 Abstract The growing number of double-responsive block copolymers with well-defined physical properties have beensynthesizedbycontrolledradical polymerization inthe last decades.These block copolymers (BCPs) can have interestingarchitecture and very complex phase behaviour, resulting in so-called "schizophrenic" micellization. It was suggested previously that BCPs consisting of a polyelectrolyte block and a thermoresponsive block may exhibit so-called "schizophrenic" micellization: In selective solvents, depending on pH and temperature, solvophilic (core-forming) blocks of these BCPs may become solvophobic (corona-forming). In this thesis, we conducted a study of double-responsive diblockcopolymer poly(di-[ethylene glycol] methyl ether methacrylate)-b-poly(2-[diisopropylamino] ethyl methacrylate) (PDEGMA-b-PDIPAEMA), inwhich PDEGMA acts as thermoresponsive blockwithLCST of 27...
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Synthesis of triblock terpolymers as a tool for preparation of smart drug delivery nanosystems
Orságh, Martin ; Uchman, Mariusz Marcin (advisor) ; Fernandez Alvarez, Roberto (referee)
In this thesis, we describe the synthesis and self-assembly of new photo-responsive triblock terpolymers by RAFT polymerization. These triblock terpolymers were characterized by GPC, NMR and IR spectroscopy. The resulting nanoparticles were characterized by DLS, SAXS and Cryo-EM. To avoid problems with RAFT polymerization of the photo-responsive monomer o- nitrobenzyl acrylate, we used naphthacyl methacrylate, a new RAFT-polymerizable photo- responsive monomer. In addition, we used phenylboronic acid moieties to conjugate model drugs with our triblock terpolymers via dynamic covalent bonding and studied stimuli-triggered release of a model drug-like compound, Alizarin Red S. Our results showed that naphthacyl methacrylate is indeed polymerizable by RAFT and that such polymers retain photo-responsive properties. We were also able to bind Alizarin Red S to the polymer via boronate ester linkage and trigger its release by dopamine or fructose addition, both of which are biologically relevant compounds. Therefore, our photo- and diol-responsive nanoparticles open up opportunities for developing new drug-delivery systems.
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Stimuli - responsive nanoparticles with boronic ester linkages as a potential carrier for drug delivery
Hlavatovičová, Eva
This thesis deals with the post-polymerization functionalization of a pH-responsive poly(styrene)-b-poly(4-vinyl pyridine)-b-poly(ethylene oxide) triblock terpolymer with stimuli responsive and diol-binding 2-bromomethyl-4-fluorophenylboronic acid and 2- bromomethyl-phenylboronic acid suitable for biomedical applications. A reproducible method of quaternization of poly(4-vinyl pyridine) block with prescriptible quaternization ratio was developed and the reaction yield was analyzed by 11 B, 1 H NMR and infrared spectroscopy. A reproducible self-assembly protocol for stable nanoparticles from functionalized stimuli-responsive triblock terpolymer was found, and the nanoparticles were studied by static, dynamic and electrophoretic light scattering, and cryogenic transmission electron microscopy. Fluorescence and UV-VIS spectroscopy measurements were performed for description of boron-ester linkages formation and hydrolysis with model drug Alizarin as a study of encapsulation and release reactions together with sugar sensing reactions for potential drug delivery.
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Post-polymerization modification of block copolymers as a tool for preparation of new drug delivery nanosystems
Marková, Pavlína ; Uchman, Mariusz Marcin (advisor) ; Košovan, Peter (referee)
Amphiphilic block copolymers self-assemble into clinically efficacious nanostructures, whose size, stability, and surface chemistry can be easily adjusted for each purpose. This versatility has prompted the vast scope of their biomedical applications, especially in the field of drug delivery. In particular, polyester-based nanoparticles have been used in gene, nucleic acid, therapeutic protein and drug delivery for their in vivo biocompatibility and biodegradability. However, most studies have only focused on amphiphilic copolymers with either short hydrophobic segments, no modification or a single preparation pathway. This diploma thesis focuses on the synthesis of poly(ethylene oxide)-b-poly(caprolactone) copolymers containing propargyl groups using two parallel approaches, namely a copolymerization with a modified monomer and a post-polymerization modification. A subsequent thiol-yne click reaction with 1-thioglycerol yielded copolymers with vicinal diols, which can reversibly bind to benzoxaborole- and boronic acid-derived compounds. Both synthetic pathways were evaluated based on macromolecular characteristics afforded by nuclear magnetic resonance spectroscopy and by size exclusion chromatography. Furthermore, we characterized the self-assembled nanoparticles by static and dynamic light...
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Procedurally Generated Landscape in Fragment Shader
Leitner, Denis ; Milet, Tomáš (referee) ; Chlubna, Tomáš (advisor)
This thesis deals with rendering of procedurally generated landscape without the use of input geometry or textures. It describes techniques for generation and realistic rendering of natural outdoor scenes. These techniques include terrain generation and realistic atmosphere and cloud rendering. Thesis also describes the use of raymarching for terrain and shadow rendering and realistic lighting for terrain which includes ambient and indirect light approximation.
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