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Interactions in solutions and gels of stimuli-responsive polymer systems investigated by NMR spectroscopy
Konefał, Rafał ; Spěváček, Jiří (advisor) ; Hrabal, Richard (referee) ; Štěpánek, Miroslav (referee)
Stimuli-responsive (stimuli-sensitive, intelligent, or smart) polymers are polymer materials which, after small external stimuli, evidently change their physical or chemical properties. Smart polymers can be classified according stimuli they respond to such as: temperature changes, mechanical stress, light irradiation, ultrasonic treatment, application of external magnetic as well as electric field, changes of pH, ionic strength, addition of the chemical agents and presence of biomolecules and bioactive molecules. Stimuli-responsive synthetic polymer systems has attracted considerable attention due to wide range of applications, i.e. controlled drug delivery and release systems, diagnostics, tissue engineering and 'smart' optical systems, as well as biosensors, microelectromechanical systems, coatings, and textiles. Among the types of stimuli for this dissertation temperature, pH and reactive oxygen species (ROS) responsive polymer systems were studied. In case of thermoresponsive polymers, when polymer chains are molecularly dissolved in a good solvent, changes (increasing or decreasing) of temperature result in insolubility (globular nanoparticles formation) of polymer chains, called temperature induced phase-separation. pH responsive polymers change properties such as: solubility, volume (gels),...
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Characterization of ultra-thin polymer films on solid substrates using different physical techniques
Pop-Georgievski, Ognen ; Rypáček, František (advisor) ; Adam, Pavel (referee) ; Werner, Carsten (referee)
The presented doctoral research was aimed at preparation and characterization of ultra thin polymer films on solid substrates using different physical techniques. Each of these physical techniques probes selectively different characteristics of the films. While some of the techniques are strong in the predetermination of some unique properties of the layers, they might be limited and give no specific/conclusive information about some other important characteristics. Therefore, only the combination of the techniques provides a profound picture of the thickness, architecture, composition and functionality of the films/layers. This combined characterization approach elucidates in details the physical characteristics and the mechanisms responsible for the unique behavior of different polymer films/layers in the application that they are intended for. In the thesis, of particular interest were films of high biomedical, biotechnological and tissue engineering importance, such as: 1. poly(lactide) films formed by grafting "from-" a silanized alacrite thin films (L605 Co-based super alloy), 2. polydopamine (PDA) films that could serve as substrate independent mod- ification platform for further surface modification steps, 3. poly(ethylene oxide)films formed by "grafting to-" PDA modified surfaces, 4....
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Interactions in solutions and gels of stimuli-responsive polymer systems investigated by NMR spectroscopy
Konefał, Rafał ; Spěváček, Jiří (advisor) ; Hrabal, Richard (referee) ; Štěpánek, Miroslav (referee)
Stimuli-responsive (stimuli-sensitive, intelligent, or smart) polymers are polymer materials which, after small external stimuli, evidently change their physical or chemical properties. Smart polymers can be classified according stimuli they respond to such as: temperature changes, mechanical stress, light irradiation, ultrasonic treatment, application of external magnetic as well as electric field, changes of pH, ionic strength, addition of the chemical agents and presence of biomolecules and bioactive molecules. Stimuli-responsive synthetic polymer systems has attracted considerable attention due to wide range of applications, i.e. controlled drug delivery and release systems, diagnostics, tissue engineering and 'smart' optical systems, as well as biosensors, microelectromechanical systems, coatings, and textiles. Among the types of stimuli for this dissertation temperature, pH and reactive oxygen species (ROS) responsive polymer systems were studied. In case of thermoresponsive polymers, when polymer chains are molecularly dissolved in a good solvent, changes (increasing or decreasing) of temperature result in insolubility (globular nanoparticles formation) of polymer chains, called temperature induced phase-separation. pH responsive polymers change properties such as: solubility, volume (gels),...
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Thin films of plasma polymers as stable supports for biomedical applications
Gordeev, Ivan ; Shukurov, Andrey (advisor) ; Novák, Rudolf (referee) ; Pavlík, Jaroslav (referee)
Title: Thin films of plasma polymers as stable supports for biomedical applications Author: Ivan Gordeev Institute: Charles University in Prague, Department of Macromolecular Physics Supervisor of the doctoral thesis: Doc. Ing. Andrey Shukurov, Ph.D, Charles University in Prague, Department of Macromolecular Physics. Abstract: Plasma polymers have been widely considered for use as bio-active coatings. In biomedicine, the surfaces that withstand accumulation of biofilms are of particular importance. This thesis is focused on development of new plasma-based methods for deposition of bio-resistant (non-fouling) plasma polymers. Poly(ethylene oxide) was the subject material. R.f. magnetron sputtering, plasma-assisted thermal vapour deposition and amplitude modulated atmospheric pressure surface dielectric barrier discharge were the methods adapted to fabricate thin films with tunable chemical composition, cross-link density and biological response. A new insight was gained into the processes of plasma polymerization as well as into composition/structure relationship and its effect on biological properties of resultant films. Keywords: plasma polymerization, PEO, 'non-fouling' properties, protein adsorption, cell adhesion
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Characterization of ultra-thin polymer films on solid substrates using different physical techniques
Pop-Georgievski, Ognen ; Rypáček, František (advisor) ; Adam, Pavel (referee) ; Werner, Carsten (referee)
The presented doctoral research was aimed at preparation and characterization of ultra thin polymer films on solid substrates using different physical techniques. Each of these physical techniques probes selectively different characteristics of the films. While some of the techniques are strong in the predetermination of some unique properties of the layers, they might be limited and give no specific/conclusive information about some other important characteristics. Therefore, only the combination of the techniques provides a profound picture of the thickness, architecture, composition and functionality of the films/layers. This combined characterization approach elucidates in details the physical characteristics and the mechanisms responsible for the unique behavior of different polymer films/layers in the application that they are intended for. In the thesis, of particular interest were films of high biomedical, biotechnological and tissue engineering importance, such as: 1. poly(lactide) films formed by grafting "from-" a silanized alacrite thin films (L605 Co-based super alloy), 2. polydopamine (PDA) films that could serve as substrate independent mod- ification platform for further surface modification steps, 3. poly(ethylene oxide)films formed by "grafting to-" PDA modified surfaces, 4....
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