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Voltammetric Determination of Flutamide at Screen-Printed Carbon Electrodes
Škvarla, Juraj ; Vyskočil, Vlastimil (advisor) ; Fischer, Jan (referee)
The paper deals with the electrochemical behaviour of flutamide at screen-printed carbon electrodes (SPCE) with the aim of optimizing conditions for their practical use in the in situ analyses. A stability of stock solution was verified and confirmed primarily. Then, an influence of pH, stirring time and flutamide concentration in the analyzed solution on the voltammetric behavior of flutamide were systematically studied using DC voltammetry and differential pulse voltammetry at SPCE. One well-developed voltammetric peak of flutamide was detected in the whole pH region investigated. The time of stirring appears to be of crucial importance for the result of measurements at all pHs. The longer time of stirring of the solution prior to measurements, the higher is the flutamide peak. Therefore, the time of stirring was set constant for the rest of measurements. The optimum conditions for voltammetric determination have been found in Britton-Robinson buffer pH 7.0 - methanol (9:1) for both DCV and DPV at SPCE. Concentration dependences were found to be linear for the range 1·10-6 - 1·10-4 mol·dm-3 and evaluable (but not reliable) up to 1·10-7 mol·dm-3 . Reached limits of quantification were 6·10-7 mol·dm-3 for DCV at SPCE and 8·10-7 mol·dm-3 for DPV at SPCE. The determination of flutamide in...
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Scattering and spectroscopic studies of polyelectrolytes and associating block copolymers
Škvarla, Juraj ; Štěpánek, Miroslav (advisor) ; Špírková, Milena (referee) ; Humpolíčková, Jana (referee)
This dissertation focuses on application of scattering and spectroscopic techniques for studies of self-assembled systems of amphiphiles (both polymeric and low-molar mass) and polyelectrolytes in aqueous solutions. Special attention was paid to optical methods, namely static, dynamic and electrophoretic light scattering and steady-state and time-resolved fluorescence spectroscopy, which were supported by a number of other techniques such as small-angle X-ray scattering or transmission electron microscopy. The dissertation brings new results regarding micellization behavior of perfluorinated surfactants, self-assembly and stability of thermoresponsive amphiphilic block copolymers and counterion condensation on polyelectrolytes in aqueous solution.
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Nanoparticles based on block copolymer complexes with fluorosurfactants
Škvarla, Juraj ; Štěpánek, Miroslav (advisor) ; Netopilík, Miloš (referee)
This thesis deals with (i) complex nanoaggregates of cationic perfluorinated surfactant N-(1,1,2,2- tetrahydroperfluorodecyl)pyridinium chloride and of double hydrophilic block polyanions poly(ethylene oxide)-b-poly(methacrylate) and poly(ethylene oxide)-b-poly((2-sulfamate-3- carboxylate)isoprene), and with (ii) mixed micelles of amphiphilic copolymer poly(ethylene oxide)- b-poly(e-caprolactone) and nonionic perfluorinated fluorosurfactant Zonyl FSN-100. The study was aimed at the characterization of the association behavior of the block copolymer-fluorosurfactant systems in aqueous solutions depending on the amount of the added surfactant, pH of the solvent and the structure of the copolymers.
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Scattering and spectroscopic studies of polyelectrolytes and associating block copolymers
Škvarla, Juraj ; Štěpánek, Miroslav (advisor) ; Špírková, Milena (referee) ; Humpolíčková, Jana (referee)
This dissertation focuses on application of scattering and spectroscopic techniques for studies of self-assembled systems of amphiphiles (both polymeric and low-molar mass) and polyelectrolytes in aqueous solutions. Special attention was paid to optical methods, namely static, dynamic and electrophoretic light scattering and steady-state and time-resolved fluorescence spectroscopy, which were supported by a number of other techniques such as small-angle X-ray scattering or transmission electron microscopy. The dissertation brings new results regarding micellization behavior of perfluorinated surfactants, self-assembly and stability of thermoresponsive amphiphilic block copolymers and counterion condensation on polyelectrolytes in aqueous solution.
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Nanoparticles based on block copolymer complexes with fluorosurfactants
Škvarla, Juraj ; Štěpánek, Miroslav (advisor) ; Netopilík, Miloš (referee)
This thesis deals with (i) complex nanoaggregates of cationic perfluorinated surfactant N-(1,1,2,2- tetrahydroperfluorodecyl)pyridinium chloride and of double hydrophilic block polyanions poly(ethylene oxide)-b-poly(methacrylate) and poly(ethylene oxide)-b-poly((2-sulfamate-3- carboxylate)isoprene), and with (ii) mixed micelles of amphiphilic copolymer poly(ethylene oxide)- b-poly(e-caprolactone) and nonionic perfluorinated fluorosurfactant Zonyl FSN-100. The study was aimed at the characterization of the association behavior of the block copolymer-fluorosurfactant systems in aqueous solutions depending on the amount of the added surfactant, pH of the solvent and the structure of the copolymers.
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Voltammetric Determination of Flutamide at Screen-Printed Carbon Electrodes
Škvarla, Juraj ; Fischer, Jan (referee) ; Vyskočil, Vlastimil (advisor)
The paper deals with the electrochemical behaviour of flutamide at screen-printed carbon electrodes (SPCE) with the aim of optimizing conditions for their practical use in the in situ analyses. A stability of stock solution was verified and confirmed primarily. Then, an influence of pH, stirring time and flutamide concentration in the analyzed solution on the voltammetric behavior of flutamide were systematically studied using DC voltammetry and differential pulse voltammetry at SPCE. One well-developed voltammetric peak of flutamide was detected in the whole pH region investigated. The time of stirring appears to be of crucial importance for the result of measurements at all pHs. The longer time of stirring of the solution prior to measurements, the higher is the flutamide peak. Therefore, the time of stirring was set constant for the rest of measurements. The optimum conditions for voltammetric determination have been found in Britton-Robinson buffer pH 7.0 - methanol (9:1) for both DCV and DPV at SPCE. Concentration dependences were found to be linear for the range 1·10-6 - 1·10-4 mol·dm-3 and evaluable (but not reliable) up to 1·10-7 mol·dm-3 . Reached limits of quantification were 6·10-7 mol·dm-3 for DCV at SPCE and 8·10-7 mol·dm-3 for DPV at SPCE. The determination of flutamide in...
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