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Interactions of polycations and anionic surfactants
Szabová, Jana ; Krouská, Jitka (referee) ; Mravec, Filip (advisor)
This thesis deals with the study of interaction polycations and anionic sufactants with regard to phase separation in water and in physiological saline solution (0.15 moldm3 NaCl). First, the solubilizing experiments were made (using hydrophobic dye red oil O) for mapping behavior system SDS-DEAE. Then the aggregation behavior of surfactant was measured. Using solubilizing experiments the area for influence of addition dextran hydrochloride for aggregation was selected. This behavior was investigated by fluorescence spectroscopy using pyrene as fluorescence probe. The Critical Micellar and Agregation Concentration of studied system was determined and defined the area of phase separation. The influence of the process of preparing hydrogels by dry or wet path was studeid. The measurements revealed that the addition of salt and polymer has a considerable influence on value of CAC. It was also found, that increasing ionic strength affects the formation of a hydrogel. Finally, it was found that the process of preparing hydrogels does not affect formation of hydrogel.
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Interaction of trimethylchitosan with Niaproof surfactant
Zbořilová, Hana ; Krouská, Jitka (referee) ; Mravec, Filip (advisor)
This thesis is focused on the study of interaction of the polycation N,N,N-trimethylchitosan (TMC) with the anionic surfactant Niaproof® 4 in water and physiological saline solution. Due to the commercial unavailability of N,N,N-trimethylchitosan, the polymer was first synthesized from chitosan, followed by NMR and FTIR characterization. Before the study of the system polycation–anionic surfactant itself, the behavior of the anionic surfactant Niaproof® 4 in aqueous solution and physiological saline solution was explored. The micellization of the surfactant Niaproof® 4 and the aggregation of TMC–Niaproof® 4 system were observed by fluorescence spectroscopy using the fluorescence probe pyrene. Values of critical micelle and critical aggregation concentration were determined on the basis of measurements. It was confirmed that presence of the sodium chloride supports the micellization by increasing the ionic strength of the solution, which leads to decrease of CMC in physiological saline solution. The interaction of TMC–Niaproof® 4 occurs at lower concentration then CMC in both aqueous and physiological environments. Phase separation occurs at higher concentrations of the surfactant leading to stabilization of the system.
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Microcalorimetric and Light Scattering Methods in the Study of Interactions in Biopolymer - Surfactant System
Šojdrová, Kamila ; Mravec, Filip (referee) ; Krouská, Jitka (advisor)
Biopolymer surfactant systems have been studied by using different physico chemical methods. As the biopolymer, it was chosen high (1400–1600 kDa), medium (250–450 kDa) and low (8–15 kDa) molecular weight sodium hyaluronate. Two cationic surfactants – cetyltrimethylammonium bromide (CTAB) and carbethopendecinium bromide (Septonex) were selected to provide polyelectrolyte complexes with oppositely charged hyaluronan. The critical aggregation concentration of the surfactant in the system was monitored by dynamic light scattering (Zetasizer Nano ZS). SEC-MALS method was used for the description of the conformation of sodium hyaluronate of different molecular weights and polyelectrolytes complexes hyaluronan surfactant after reaching the aggregation point. Isothermal titration calorimetry (ITC) was used to determine the critical aggregation concentration of the surfactant by monitoring the thermal changes accompanying the aggregation of the system. It was found out that the increasing molecular weight of hyaluronan in these systems decreases the critical aggregation concentrations and conversely.
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Interaction of trimethylchitosan with Niaproof surfactant
Zbořilová, Hana ; Krouská, Jitka (referee) ; Mravec, Filip (advisor)
This thesis is focused on the study of interaction of the polycation N,N,N-trimethylchitosan (TMC) with the anionic surfactant Niaproof® 4 in water and physiological saline solution. Due to the commercial unavailability of N,N,N-trimethylchitosan, the polymer was first synthesized from chitosan, followed by NMR and FTIR characterization. Before the study of the system polycation–anionic surfactant itself, the behavior of the anionic surfactant Niaproof® 4 in aqueous solution and physiological saline solution was explored. The micellization of the surfactant Niaproof® 4 and the aggregation of TMC–Niaproof® 4 system were observed by fluorescence spectroscopy using the fluorescence probe pyrene. Values of critical micelle and critical aggregation concentration were determined on the basis of measurements. It was confirmed that presence of the sodium chloride supports the micellization by increasing the ionic strength of the solution, which leads to decrease of CMC in physiological saline solution. The interaction of TMC–Niaproof® 4 occurs at lower concentration then CMC in both aqueous and physiological environments. Phase separation occurs at higher concentrations of the surfactant leading to stabilization of the system.
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Microcalorimetric and Light Scattering Methods in the Study of Interactions in Biopolymer - Surfactant System
Šojdrová, Kamila ; Mravec, Filip (referee) ; Krouská, Jitka (advisor)
Biopolymer surfactant systems have been studied by using different physico chemical methods. As the biopolymer, it was chosen high (1400–1600 kDa), medium (250–450 kDa) and low (8–15 kDa) molecular weight sodium hyaluronate. Two cationic surfactants – cetyltrimethylammonium bromide (CTAB) and carbethopendecinium bromide (Septonex) were selected to provide polyelectrolyte complexes with oppositely charged hyaluronan. The critical aggregation concentration of the surfactant in the system was monitored by dynamic light scattering (Zetasizer Nano ZS). SEC-MALS method was used for the description of the conformation of sodium hyaluronate of different molecular weights and polyelectrolytes complexes hyaluronan surfactant after reaching the aggregation point. Isothermal titration calorimetry (ITC) was used to determine the critical aggregation concentration of the surfactant by monitoring the thermal changes accompanying the aggregation of the system. It was found out that the increasing molecular weight of hyaluronan in these systems decreases the critical aggregation concentrations and conversely.
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Interactions of polycations and anionic surfactants
Szabová, Jana ; Krouská, Jitka (referee) ; Mravec, Filip (advisor)
This thesis deals with the study of interaction polycations and anionic sufactants with regard to phase separation in water and in physiological saline solution (0.15 moldm3 NaCl). First, the solubilizing experiments were made (using hydrophobic dye red oil O) for mapping behavior system SDS-DEAE. Then the aggregation behavior of surfactant was measured. Using solubilizing experiments the area for influence of addition dextran hydrochloride for aggregation was selected. This behavior was investigated by fluorescence spectroscopy using pyrene as fluorescence probe. The Critical Micellar and Agregation Concentration of studied system was determined and defined the area of phase separation. The influence of the process of preparing hydrogels by dry or wet path was studeid. The measurements revealed that the addition of salt and polymer has a considerable influence on value of CAC. It was also found, that increasing ionic strength affects the formation of a hydrogel. Finally, it was found that the process of preparing hydrogels does not affect formation of hydrogel.
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