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PREPARATION AND CHARACTERIZATION OF BIOPOLYMER-BASED NANOPARTICLES AND NANOFIBERS AND THEIR APPLICATION IN FOOD AND COSMETICS
Kundrát, Vojtěch ; Vilčáková, Jarmila (referee) ; Kráčmar, Stanislav (referee) ; Márová, Ivana (advisor)
The presented dissertation thesis deals with the polymer polyhydroxybutyrate and other biopolymers as a basic building block for the construction of micro- and nanoscopic structures and materials used in food and cosmetics. In the theoretical part, current literary review is prepared to introduce the basics of this application field. The practical part of the work is composed of three blocks developed during the doctoral study. In the first and most important part are summarized comments to the academic and patent outputs, where among the academic ones it is possible to find two peer-reviewed articles dealing with the electrostatic and wet spinning of PHB and properties of prepared materials. The patent outputs consist of several accepted and applied projects, which summarize results on both PHB spinning methods, but also on general approaches enabling the processing of PHB into forms enabling many applications in food and cosmetics. Second part was focused on the patented composition of the UV protection cream based on the prepared nanoscopic and micro- morphologies of PHB. The third block summarizes results focused predominantly on the electrostatic spinning of PHB and other biopolymers. Finally, a short chapter containing a brief description of projects that were in a way related to the dissertation topic, but rather practical development work in Central Tanzania and West Africa, which draw on knowledge and contacts gained during studies at FCH BUT Brno.
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The influence of PEO source on nanofiber layer preparation
Grufíková, Jana ; Knotek,, Petr (referee) ; Knotková, Kateřina (advisor)
The electrospinning process of polymer solutions is affected by many different parameters that can be divided into solution parameters, process parameters, and ambient parameters. This study is focused on characteristics of a polymer and its solution, which are ranging into the solution parameters. The aim of this study is to compare poly(ethylene oxide) characteristics in the relation to electrospinning of hyaluronic acid, to find the difference between them using available analytic, thermic and spectral methods, and to define the influence of properties on polymeric solutions behavior during electrospinning. It was find that poly(ethylene oxides) obtained from two different sources behave differently in an electrostatic field, although their molar mass is declared as the same. It was also confirmed that the electrospinning process of polymeric solutions is affected mainly by their viscosity and conductivity. This two properties are determined especially by the molar mass of polymer and also by the content of impurities or content of some another polymer during electrospinning of mixed solution.
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Electrospinning of Modified Biopolymers for Medical Applications
Pavliňáková, Veronika ; Martinová,, Lenka (referee) ; Zajíčková, Lenka (referee) ; Vojtová, Lucy (advisor)
Předkládaná disertační práce se zabývá přípravou a charakterizací nových biokompatibilních nanovláken s potenciální aplikací v medicíně. V této práci byl výběr jednotlivých složek pro přípravu nanovlákenného materiálu zvolen tak, aby vyhovoval nárokům tkáňového inženýrství. Literární rešerše shrnuje poznatky o elektrostatickém zvlákňování a o jeho parametrech. Dále se věnuje možnostem elektrostatického zvlákňování proteinů kolagenu a želatiny a jejich směsmi se syntetickými polymery a biopolymery a anorganickými plnivy. Teoretická část řeší také různé postupy síťování nanovláken vedoucí ke zlepšení jejich hydrolytické stability a mechanických vlastností. Poslední část je zaměřena na anorganické nanotrubky halloysitu (HNT), které získaly svou pozornost díky svým vynikajícím fyzikálním a biologickým vlastnostem. V experimentální části byly zpracovány dvě případové studie, z nichž každá se zabývá přípravou nanovlákenných biomateriálů s potenciální aplikací v medicíně. První studie je zaměřena na přípravu a charakterizaci nových hydrolyticky stabilních antibakteriálních želatinových nanovláken modifikovaných pomocí oxidované celulózy. Unikátní inhibiční účinky nanovláken byly testovány na kmenu bakterie Escherichia coli pomocí metody chemické bioluminiscence. Kultivované buňky lidského papilárního adenokacinomu plic prokázaly dobrou adhezi a proliferaci k povrchu nanovláken. Druhá část popisuje vliv zdroje a množství anorganických halloysitových nanotrubek na strukturu a vlastnosti amfifilních nanovláken ze směsi želatiny a syntetického polykaprolaktonu. Přídavek HNT zlepšil tepelnou stabilitu, mechanické vlastnosti (jak tuhost, tak prodloužení) a snížil krystalinitu nanovláken. HNT z různých zdrojů neměl vliv na chování buněk, ale mírně ovlivnil proliferaci a životaschopnost buněk na povrchu nanovláken.
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Determination of additives in multicomponent electrospinning systems
Gajdová, Barbora ; Petr, Knotek (referee) ; Knotková,, Kateřina (advisor)
This bachelor thesis deals with methods of producing nanofibres from mixture of different polymers. Different methods of preparation and production nanofibres by 4SPIN® are described in theoretical part. Experimental part deals with incorporation of additives into fibred layer. There were four different dyes used in this thesis: brilliant green, erythrosine, riboflavin and eriochrom black. UV – VIS spectrophotometry was used to measure volume of additives in nanofiber layer.
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Effect of pH on quantitative determination of additives in nanofibers
Grufíková, Jana ; Marek, Pokorný (referee) ; Knotková,, Kateřina (advisor)
The object of my thesis was to prepare a nanofiber layer with dye additives and to quantify the additive content in dependence on pH. The nanofiber layers with additives were prepared by means of electrospinning. The analysis of the additive content in samples was performed by UV-VIS spectrophotometry. Concretely Erythrosine, Eriochrome Black, Riboflavin and Brilliant Blue were analysed. Each of this colors has different chemical structure and charge. The pH was defined by use of buffers, namely acetate buffer (pH 5), phosphate buffer (pH 7,4) and carbonate buffer (pH 10). For Erythrosine and Eriochrome Black the research was extended to study the effect of ionic strength on the quantitative determination of these dyes. It was found that the quantity of the determined additive depends on the pH and also on the ionic strength. However, this dependency is different for each additive. This confirms the assumption of influenced chemical structure and charge by interaction with polymers and buffers used in this experiment. The accuracy of evaluation is influenced by the way of data processing.
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