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Hyaluronan-CTAT hydrogels
Velcer, Tomáš ; Venerová, Tereza (referee) ; Pekař, Miloslav (advisor)
This thesis studies the properties and behaviour of phase-separated hydrogels prepared by interaction of hyaluronan with oppositely charged surfactants. Three representatives of surfactants, namely cetyltrimethylammonium bromide, chloride and p-toluensulfonate (CTAB, CTAC, CTAT), were selected for comparison. Using the method of rheology, the fact that the system of Hya-CTAT forms the most rigid hydrogels has been proved. Higher molecular weight of hyaluronan has also direct influence on the volume and stiffness of the newly formed hydrogels. Preparation methods were compared as well. Mixing the stock solutions of entry components appeard to be the most suitable. Small-angle X-ray scattering was used for determination of shape and size of surfactant's micelles, concluding that it has no effect on the volume of formed gels. The results of this study indicate that given gels are to a certain extent competitive and incorporation of hyaluronan into their structure is desirable with respect to its biological activity. This offers a potential usage of these substances in the field of medical applications.
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Preparation and characterization of nanoparticles for in vitro cell studies
Hladík, Martin ; Černoch, Peter (advisor) ; Pilař, Jan (referee)
This thesis deals with the preparation, characterization methods and in vitro imaging of nanoparticles with great potential for medical diagnostics. A key role in this work occupy nanoparticles comprising a core of calcium tungstate, CaWO4, covered by a natural polysaccharide together serve as a suitable model contrast agent for cell imaging techniques. CaWO4 natural properties such as the absorption of X-rays, natural fluorescence capabilities and capacities for doping fluorescently active lanthanides, makes from nanoparticles suitable candidates for the position of contrast agents for imaging in the diagnosis of oncological diseases. Moreover, by coverage of the inorganic core by natural polysaccharide nanoparticles reach the desired size and the possibility of active targeting to specific or nonspecific interactions with the cell membrane, which are key factors in in vitro cell studies. It was found the most suitable synthesis both doped and undoped core of this model reaching the formation of spherical particles of colloidal dimensions. Doping was realized by red fluorescent trivalent europium, Eu3+ , and green fluorescent trivalent terbium, Tb3+ , and neither of these dopants affected the original crystalline structure CaWO4. In the next stage, these fluorescent nuclei successfully dispersed...
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Hyaluronan-CTAT hydrogels
Velcer, Tomáš ; Venerová, Tereza (referee) ; Pekař, Miloslav (advisor)
This thesis studies the properties and behaviour of phase-separated hydrogels prepared by interaction of hyaluronan with oppositely charged surfactants. Three representatives of surfactants, namely cetyltrimethylammonium bromide, chloride and p-toluensulfonate (CTAB, CTAC, CTAT), were selected for comparison. Using the method of rheology, the fact that the system of Hya-CTAT forms the most rigid hydrogels has been proved. Higher molecular weight of hyaluronan has also direct influence on the volume and stiffness of the newly formed hydrogels. Preparation methods were compared as well. Mixing the stock solutions of entry components appeard to be the most suitable. Small-angle X-ray scattering was used for determination of shape and size of surfactant's micelles, concluding that it has no effect on the volume of formed gels. The results of this study indicate that given gels are to a certain extent competitive and incorporation of hyaluronan into their structure is desirable with respect to its biological activity. This offers a potential usage of these substances in the field of medical applications.
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