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Time-resolved fluorescence in investigation of colloid system
Černá, Ladislava ; Ouzzane, Imad (referee) ; Mravec, Filip (advisor)
This thesis is focused on determination of the basic spectral characteristics, such as fluorescence maximum and lifetime, of fluorescent probes prodan [6-propionyl-2-(dimethylamino)naphthalene] and perylene by steady-state and time-resolved fluorescence spectroscopy. Time-resolved measurements were realized through TCSPC method (time-correlated single photon counting). The characteristics of prodan were found in water, acetone, n-heptane and in mixtures of these, so that a polar scale of environments would arise. Both of the mentioned probes were further investigated in systems of aqueous solutions of hyaluronic acid (300 kDa) at the concentration of 10 mg•l-1 together with cationic surfactant CTAB (cetyltrimethylammonium bromide) at the concentration range from 0.01 to 0.20 mmol•l-1 (before CMC). The aim was to confirm the reach and the range of critical aggregation concentration of the surfactant (CAC), to uncover the basic spectral characteristics of the mentioned probes in this concentration range and to verify the stability of this system in the presence of NaCl at the concentration of 0.15 mol•l-1. Furthermore, by TCSPC method were obtained time-resolved emission spectra of prodan from the system of hyaluronic acid and CTAB at one concentration of CTAB in CAC interval both without salt and with salt at the concentration of 0.15 mol•l-1. The obtained time-resolved emission spectra correlated with the results of the CAC concentration range measurement. After addition of salt the system of CAC proved to be unstable.
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Time-resolved fluorescence study of liquid and condensed systems based on biopolymer-surfactant interactions.
Černá, Ladislava ; Žitňan, Michal (referee) ; Mravec, Filip (advisor)
This thesis studies properties of hydrogel, which arises on the basis of electrostatic and hydrophobic interactions between hyaluronan chain and micelles of cationic surfactant. A native sodium hyaluronan at molecular weight 750–1 000 kDa and a cationic surfactant CTAB (cetyltrimethylammonium bromide) were used. This hydrogel was assessed as a material for drug delivery systems. The hydrogels were made by mixing 200mM CTAB with 0.5% hyaluronan, both dissolved in 0.15M aqueous solution of NaCl simulating physiological solution. Methods used in this study were steady-state and time-resolved fluorescence spectroscopy, more accurately time-resolved emission spectra (TRES) and deconvolution of steady-state emission spectra of a whole sample by means of parameters gained from fluorescence intensity decays at a set of wavelenghts. Selected systems were investigated by three fluorescent probes, prodan, laurdan and rhodamine 6G. The first two mentioned probes were in hydrogel localized only within micelles in three different microenvironments. Rhodamine 6G pointed out that in hydrogel the aqueous environment is significantly restricted in comparison to purely micellar solution. In addition, rhodamine informed about less available micelle surfaces, caused by hyaluronan chains occupation. There were no interactions between the probes and hyaluronan chains. Freshly made hydrogels showed almost the same results as after a week of maturation under its supernatant.
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Professional Education of Pharmacy Assistants in the Czech Republic
Krupková, Alena ; Kotlářová, Jana (advisor) ; Černá, Ladislava (referee)
PROFESSIONAL EDUCATION OF PHARMACY ASSISTANS IN THE CZECH REPUBLIC Author: Alena Krupková Supervisor of the diploma thesis: RNDr. Jana Kotlářová Ph.D. Department of Social and Clinical Pharmacy, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, the Czech Republic INTRODUCTION: The aim of the present diploma thesis is to map the area of the professional preparation of the pharmaceutical assistants in the Czech Republic before they commence career and after that. OBJECTIVE: To examine how the conditions of the undergraduate and postgraduate studies are perceived from the very perspective of the pharmaceutical assistants, which positives and negatives they find in relation to these questions. On the basis of the evaluated data, to suggest possible ways of eliminating demerits and improving the current education system. METHODS: For the method of research, questionnaires focusing on the opinions of respondents-the pharmaceutical assistants- on the subject were used. Both paper and electronic questionnaires were used and during the period starting in November 2010 and ending in October 2011 we were able to assemble 140 filled out questionnaires. The main database consisted of them. The programme that was used to process the data was Microsoft Excel RESULTS: Among the most important...
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Time-resolved fluorescence study of liquid and condensed systems based on biopolymer-surfactant interactions.
Černá, Ladislava ; Žitňan, Michal (referee) ; Mravec, Filip (advisor)
This thesis studies properties of hydrogel, which arises on the basis of electrostatic and hydrophobic interactions between hyaluronan chain and micelles of cationic surfactant. A native sodium hyaluronan at molecular weight 750–1 000 kDa and a cationic surfactant CTAB (cetyltrimethylammonium bromide) were used. This hydrogel was assessed as a material for drug delivery systems. The hydrogels were made by mixing 200mM CTAB with 0.5% hyaluronan, both dissolved in 0.15M aqueous solution of NaCl simulating physiological solution. Methods used in this study were steady-state and time-resolved fluorescence spectroscopy, more accurately time-resolved emission spectra (TRES) and deconvolution of steady-state emission spectra of a whole sample by means of parameters gained from fluorescence intensity decays at a set of wavelenghts. Selected systems were investigated by three fluorescent probes, prodan, laurdan and rhodamine 6G. The first two mentioned probes were in hydrogel localized only within micelles in three different microenvironments. Rhodamine 6G pointed out that in hydrogel the aqueous environment is significantly restricted in comparison to purely micellar solution. In addition, rhodamine informed about less available micelle surfaces, caused by hyaluronan chains occupation. There were no interactions between the probes and hyaluronan chains. Freshly made hydrogels showed almost the same results as after a week of maturation under its supernatant.
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Time-resolved fluorescence in investigation of colloid system
Černá, Ladislava ; Ouzzane, Imad (referee) ; Mravec, Filip (advisor)
This thesis is focused on determination of the basic spectral characteristics, such as fluorescence maximum and lifetime, of fluorescent probes prodan [6-propionyl-2-(dimethylamino)naphthalene] and perylene by steady-state and time-resolved fluorescence spectroscopy. Time-resolved measurements were realized through TCSPC method (time-correlated single photon counting). The characteristics of prodan were found in water, acetone, n-heptane and in mixtures of these, so that a polar scale of environments would arise. Both of the mentioned probes were further investigated in systems of aqueous solutions of hyaluronic acid (300 kDa) at the concentration of 10 mg•l-1 together with cationic surfactant CTAB (cetyltrimethylammonium bromide) at the concentration range from 0.01 to 0.20 mmol•l-1 (before CMC). The aim was to confirm the reach and the range of critical aggregation concentration of the surfactant (CAC), to uncover the basic spectral characteristics of the mentioned probes in this concentration range and to verify the stability of this system in the presence of NaCl at the concentration of 0.15 mol•l-1. Furthermore, by TCSPC method were obtained time-resolved emission spectra of prodan from the system of hyaluronic acid and CTAB at one concentration of CTAB in CAC interval both without salt and with salt at the concentration of 0.15 mol•l-1. The obtained time-resolved emission spectra correlated with the results of the CAC concentration range measurement. After addition of salt the system of CAC proved to be unstable.
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