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Advanced Fluorescence Techniques in Research on Micellar Systems and Their Interactions with Biopolymers
Holínková, Petra ; Burgert, Ladislav (referee) ; Táborský, Petr (referee) ; Pekař, Miloslav (advisor)
The dissertation thesis deals with study of advanced steady-state and time-resolved fluorescence techniques, which can be used for study of micellar systems properties. Selected fluorescence techniques were used for characterization of Septonex and CTAB cationic micellar systems and theirs interactions with hyaluronan. Fluorescent probe pyrene was used for determination of critical micelle concentration (CMC) and micellar aggregation number of these surfactants. The changes of fluorescence behaviour of fluorescein and prodan were studied in wide concentration range of Septonex. Next chapter of thesis deals with study of Förster resonance energy transfer between perylene and fluorescein in Septonex and CTAB micellar solutions and the effect of hyaluronan addition to these systems. Also steady-state and time-resolved fluorescence anisotropy studies were used for research of the effect of hyaluronan addition to micellar solutions. The last chapter of this thesis is focused on photophysical behaviour of Prodan in different solutions (water, Septonex solutions below CMC, hyaluronan solution, Septonex micellar solution and Septonex micellar solution with hyaluronan), which was discussed on the basis of time-resolved emission spectra.
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Model delivery systems for poorly soluble drugs
Sapárová, Alica ; Holínková, Petra (referee) ; Pilgrová, Tereza (advisor)
The solubilizing capacity of micelle–hyaluronan system was studied using the UV-VIS spectrophotometry method. Septonex was chosen as a surfactant and four molecular weights of hyaluronan were used. Solubilization experiments with a hydrophobic dye Sudan Red G and Sudan III were performed in order to obtain a model system of solubilized drugs, which are also hydrophobic. The system was prepared in the environment of mili-Q water. The influence of the molecular weight of hyaluronan on the solubilizing ability has been studied. It was found that concentration of solubilized dyes increases by increasing concentration of micelles in the system and the molecular weight of hyaluronan affects the solubility of the dyes.
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Quality of hydrophobic domains in polyelectrolyte-surfactant system
Holínková, Petra ; Vala, Martin (referee) ; Mravec, Filip (advisor)
In this bachelor thesis were studied the photophysical properties of four fluorescent probes depending on the viscosity of their surroundings by the fluorescence spectroscopy. For probes DPH, DPB a perylene was determinated dependence of fluorescence anisotropy and for P3P dependence of ratio excimer/monomer on the viscosity of the sample. Anisotropy probes DPH and perylene were also used to study interaction between hyaluronan and cationic surfactant CTAB (concentration below CMC) in aqueous solution and 0,15 M NaCl. Information about forming hydrophobic domains were obtained by measurement of fluorescence intensity and anisotropy depending on the concentration of CTAB in the sample. It was found that in an aqueuos solution, after the initial addition of CTAB to hyaluronan formed small hydrophobic domains linked to chain of hyaluronan. Increasing concentration of CTAB leads to the formation of gel and phase separation. After addition of NaCl leads to reorganization of this system and probably the formation of free micelles in the solution with higher concentration of CTAB.
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Anisotropy and time-resolved anisotropy techniques in colloidal systems research
Holínková, Petra ; Táborský,, Petr (referee) ; Mravec, Filip (advisor)
In this diploma thesis were investigated in terms of microviscosity liquid and condensed systems composed of hyaluronan (Hya) and cationic surfactant cetyltrimethylammonium bromide (CTAB). The excitation and emission spectra, lifetime, steady-state fluorescence anisotropy and time-resolved fluorescence anisotropy of the samples were measured. First, was studied the formation of hydrophobic domains in the system Hya-CTAB at concentration of CTAB lower than its critical micelle concentration in an aqueous solution and 0.15M NaCl. It was found that in an aqueous solution small hydrophobic domains linked to chains Hya are formed. Then an increasing concentration of CTAB leads to phase separation and formation of gel. Due to the addition of NaCl then leads to the reorganization of this system and probably the formation of free micelles in the solution. Were also studied condensed phase of system Hya-CTAB-NaCl at high concentrations of surfactant during fourteen days of ageing. It was found that the microviscosity of hydrophobic domains is constant, but the microviscosity of hydrophilic parts gradually decreases.
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Advanced Fluorescence Techniques in Research on Micellar Systems and Their Interactions with Biopolymers
Holínková, Petra ; Burgert, Ladislav (referee) ; Táborský, Petr (referee) ; Pekař, Miloslav (advisor)
The dissertation thesis deals with study of advanced steady-state and time-resolved fluorescence techniques, which can be used for study of micellar systems properties. Selected fluorescence techniques were used for characterization of Septonex and CTAB cationic micellar systems and theirs interactions with hyaluronan. Fluorescent probe pyrene was used for determination of critical micelle concentration (CMC) and micellar aggregation number of these surfactants. The changes of fluorescence behaviour of fluorescein and prodan were studied in wide concentration range of Septonex. Next chapter of thesis deals with study of Förster resonance energy transfer between perylene and fluorescein in Septonex and CTAB micellar solutions and the effect of hyaluronan addition to these systems. Also steady-state and time-resolved fluorescence anisotropy studies were used for research of the effect of hyaluronan addition to micellar solutions. The last chapter of this thesis is focused on photophysical behaviour of Prodan in different solutions (water, Septonex solutions below CMC, hyaluronan solution, Septonex micellar solution and Septonex micellar solution with hyaluronan), which was discussed on the basis of time-resolved emission spectra.
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The media image of the fair trade concept in the Czech press
Holinková, Petra ; Hronová, Tereza (advisor) ; Křeček, Jan (referee)
The thesis The media image of the Fair Trade concept in the Czech press examines media image of the Fair Trade business system in the most widely read newspapers Aha!, Blesk, Hospodářské noviny, Lidové noviny, Mladá fronta DNES, Právo and Sport. The aim is to find out whether newspapers report on Fair Trade in broader context and in which frames it is most likely presented. At the same time the thesis examines the extent to which newspapers inform about Fair Trade. There are two hypothesis formulated, one suggesting that the amount of articles referring about Fair trade has an increasing tendency and that articles do not address the issue in broader context. The answers to research questions and the validity of the hypotheses are examined through quantitative and qualitative content analysis based primarily on the framework theory. Deductive procedure using pre-formulated control questions is also used. The finding is that the newspapers most often present Fair Trade in economics frame followed by conflict frame and human impact frame. In addition, the thesis examines the presence of a critical frame, which is almost absent in the newspapers. The context is usually limited. The amount of articles about Fair Trade is decreasing during the monitored period of time. So the validity of the hypothesis...
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Vliv barvy překážky na kvalitu výkonu koně
HOLINKOVÁ, Petra
This diploma work deals with what influence the colour (red, yellow, green and blue) of an obstacle has on the jumping performance of horses. Eleven horses of different ages and breeds which are used for both recreational as well as sport riding purposes participated in the trial. The success of the horses at jumping over obstacles of variours colours was evaluated in relation to other selected variables, namely gender, age, height of the jump, and the type of riding surface. The horses were most successful at jumping yellow (96.4%) and red (95.2%) obstacles, whilst being less successful over green (85.7%) and blue (83.3%) ones. A successful jump included those where the front or hind hoof touched the obstacle without actually knocking the obstacle down. The values for touching the obstacle with the front or hind hoof were approximately the same for the red (7.1%) and green (9.5%) obstacles. With the yellow obstacles, there was a higher percentage of touching with the front hoof (11.9%) than the hind hoof (4.7%). With the blue obstacles, there was also a higher percentage of touching with the front hoof (10.7%) than the hind hoof (9.5%), although the difference was not as marked as with the yellow obstacles. The influence of the other selected variables on the jumping performance of the horses over the different coloured obstacles was diverse. The values of the correlation coefficients for gender and the type of riding surface did not prove there was a statistically significant influence of the horse´s success. In contrast, statistically significant relationships were proven for the height of a jump which was green, with a correlation coefficient rxy = -0.236+ (i.e. the higher the green jump the less successful the jumps), or yellow, with a correlation coefficient rxy = -0.377+++ (i.e. the older the horse the less successful the jumps).
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Anisotropy and time-resolved anisotropy techniques in colloidal systems research
Holínková, Petra ; Táborský,, Petr (referee) ; Mravec, Filip (advisor)
In this diploma thesis were investigated in terms of microviscosity liquid and condensed systems composed of hyaluronan (Hya) and cationic surfactant cetyltrimethylammonium bromide (CTAB). The excitation and emission spectra, lifetime, steady-state fluorescence anisotropy and time-resolved fluorescence anisotropy of the samples were measured. First, was studied the formation of hydrophobic domains in the system Hya-CTAB at concentration of CTAB lower than its critical micelle concentration in an aqueous solution and 0.15M NaCl. It was found that in an aqueous solution small hydrophobic domains linked to chains Hya are formed. Then an increasing concentration of CTAB leads to phase separation and formation of gel. Due to the addition of NaCl then leads to the reorganization of this system and probably the formation of free micelles in the solution. Were also studied condensed phase of system Hya-CTAB-NaCl at high concentrations of surfactant during fourteen days of ageing. It was found that the microviscosity of hydrophobic domains is constant, but the microviscosity of hydrophilic parts gradually decreases.
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Model delivery systems for poorly soluble drugs
Sapárová, Alica ; Holínková, Petra (referee) ; Pilgrová, Tereza (advisor)
The solubilizing capacity of micelle–hyaluronan system was studied using the UV-VIS spectrophotometry method. Septonex was chosen as a surfactant and four molecular weights of hyaluronan were used. Solubilization experiments with a hydrophobic dye Sudan Red G and Sudan III were performed in order to obtain a model system of solubilized drugs, which are also hydrophobic. The system was prepared in the environment of mili-Q water. The influence of the molecular weight of hyaluronan on the solubilizing ability has been studied. It was found that concentration of solubilized dyes increases by increasing concentration of micelles in the system and the molecular weight of hyaluronan affects the solubility of the dyes.
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Quality of hydrophobic domains in polyelectrolyte-surfactant system
Holínková, Petra ; Vala, Martin (referee) ; Mravec, Filip (advisor)
In this bachelor thesis were studied the photophysical properties of four fluorescent probes depending on the viscosity of their surroundings by the fluorescence spectroscopy. For probes DPH, DPB a perylene was determinated dependence of fluorescence anisotropy and for P3P dependence of ratio excimer/monomer on the viscosity of the sample. Anisotropy probes DPH and perylene were also used to study interaction between hyaluronan and cationic surfactant CTAB (concentration below CMC) in aqueous solution and 0,15 M NaCl. Information about forming hydrophobic domains were obtained by measurement of fluorescence intensity and anisotropy depending on the concentration of CTAB in the sample. It was found that in an aqueuos solution, after the initial addition of CTAB to hyaluronan formed small hydrophobic domains linked to chain of hyaluronan. Increasing concentration of CTAB leads to the formation of gel and phase separation. After addition of NaCl leads to reorganization of this system and probably the formation of free micelles in the solution with higher concentration of CTAB.
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