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Utilization of Light Scattering for the Study on the Structural and Conformation Changes during the Interaction of Biopolymers
Dobiášová, Andrea ; Hurčíková, Andrea (referee) ; Kalina, Michal (advisor)
The aim of this bachelor thesis was to study structural and conformation changes during the interaction of biopolymers by ligth scattering methods. This study was focused on hyaluronic acid with two molecular weights 250 – 450 kDa and 1500 – 1750 kDa, on sodium alginate and dextran hydrochloride (DEAE). NaCl, CaCl2 and BSA were used as interacting agents. Simple physical-chemical methods, like UV-VIS spectrometry, dynamic and electrophoretic light scattering, were used in experimental part. The main used method for these purposes was size exclusion chromatography coupled with light scattering and viscosimetry detectors. The studied characteristics of experiment were molecular weight, gyration and hydrodynamic radius, zeta potential and coefficients of conformation and Mark-Howinks diagrams. Interactions have been proved between negatively charged polyelectrolytes and additives. NaCl practically did not interact with any polysaccharide, only increasing ionic strength. Positively charged dextran interacted only with the BSA, despite having the same charge.
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Structure and Transport Properties of Semi-IPN Hydrogels Based on Polyvinyl Alcohol
Dobiášová, Andrea ; Smilek, Jiří (referee) ; Kalina, Michal (advisor)
The aim of master thesis was to study structural and transport properties of PVA films modified with method of semi-IPN with suitable polyectrolytes and plasticizers. The first important step was optimalization of PVA films preparation, when time of heating was set at 90 °C for 1 hour. Drying was set at 50 °C for 24 hours. Molecular weight of PVA was chosen 85–124 kDa in concentration 10 wt.%. For preparation of PVA-based semi-IPN thin films polyelectrolytes (polyglutamic acid, DEAE-dextran hydrochloride) and plasticizer (glycerol) were selected. Basic characterization of prepared materials was performed with FTIR, TGA, SEM and specific surface analysis. The difference between modified PVA films was in the chargé of individual functional groups carried by used polyelectrolytes. Surfaces of all the PVA films were smooth without visible defects. Transport properties were characterized with the method of horizontal diffusion cell with methylen blue used as a probe. Diffusion coefficients of methylen blue through PVA films were determined. It was found, that the fastest pass was throw PVA film without additives. The slowest diffusion was observed through PVA/DEAE-dextran film, because of the same charge of the film with a probe. PVA/PGA reacted with methylen blue to form a complex. Plasticizer effect on the diffusion was only minor; it caused a slight decrease of diffusion coefficient. These films were easier to handle.
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Structure and Transport Properties of Semi-IPN Hydrogels Based on Polyvinyl Alcohol
Dobiášová, Andrea ; Smilek, Jiří (referee) ; Kalina, Michal (advisor)
The aim of master thesis was to study structural and transport properties of PVA films modified with method of semi-IPN with suitable polyectrolytes and plasticizers. The first important step was optimalization of PVA films preparation, when time of heating was set at 90 °C for 1 hour. Drying was set at 50 °C for 24 hours. Molecular weight of PVA was chosen 85–124 kDa in concentration 10 wt.%. For preparation of PVA-based semi-IPN thin films polyelectrolytes (polyglutamic acid, DEAE-dextran hydrochloride) and plasticizer (glycerol) were selected. Basic characterization of prepared materials was performed with FTIR, TGA, SEM and specific surface analysis. The difference between modified PVA films was in the chargé of individual functional groups carried by used polyelectrolytes. Surfaces of all the PVA films were smooth without visible defects. Transport properties were characterized with the method of horizontal diffusion cell with methylen blue used as a probe. Diffusion coefficients of methylen blue through PVA films were determined. It was found, that the fastest pass was throw PVA film without additives. The slowest diffusion was observed through PVA/DEAE-dextran film, because of the same charge of the film with a probe. PVA/PGA reacted with methylen blue to form a complex. Plasticizer effect on the diffusion was only minor; it caused a slight decrease of diffusion coefficient. These films were easier to handle.
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Utilization of Light Scattering for the Study on the Structural and Conformation Changes during the Interaction of Biopolymers
Dobiášová, Andrea ; Hurčíková, Andrea (referee) ; Kalina, Michal (advisor)
The aim of this bachelor thesis was to study structural and conformation changes during the interaction of biopolymers by ligth scattering methods. This study was focused on hyaluronic acid with two molecular weights 250 – 450 kDa and 1500 – 1750 kDa, on sodium alginate and dextran hydrochloride (DEAE). NaCl, CaCl2 and BSA were used as interacting agents. Simple physical-chemical methods, like UV-VIS spectrometry, dynamic and electrophoretic light scattering, were used in experimental part. The main used method for these purposes was size exclusion chromatography coupled with light scattering and viscosimetry detectors. The studied characteristics of experiment were molecular weight, gyration and hydrodynamic radius, zeta potential and coefficients of conformation and Mark-Howinks diagrams. Interactions have been proved between negatively charged polyelectrolytes and additives. NaCl practically did not interact with any polysaccharide, only increasing ionic strength. Positively charged dextran interacted only with the BSA, despite having the same charge.
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