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Study of interactions of hyaluronan-amino acids
Jugl, Adam ; Smilek, Jiří (referee) ; Hurčíková, Andrea (advisor)
The master´s thesis deals with the study of the interaction between the polysaccharide hyaluronan of diffrerent molecular weights with the amino acids arginine, lysine, arginine hydrochloride and 6-aminocaproic acid. They are expected interaction between carboxyl groups of hyaluronan and amino groups of amino acids. These interactions were investigated by using ultrasonic spectroscopy, DLS, measuring pH and conductivity. Obtained results were compared with sodium polystyrene sulfonate. With ultrasonic spectroscopy was observed a change of concentration inkrement for titration of amino acid to water or polymers solutions especially for high molecular weight hyaluronan and for NaPSS in combination with 6AKK in concentration range of added amino acid 0–30 mM. The size of this change could mean a degree of interaction between polymers and amino acids. This theory has not been confirmed by other methods. By pH and conductivity measurements interations between arginine and low molecular weight hyaluronan and NaPSS were only confirmed. There was no possibility to make unequivocal conclusions from determination of particle size and zeta potential by DLS. Overall, the issue of the interaction of amino acids with polyanions was proved above expectations complex and will be appropriate to further expand the observations made in this thesis.
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Dynamic light scattering and electroanalytical investigation of hyaluronan-amino acids systems
Muchová, Johana ; Kalina, Michal (referee) ; Chytil, Martin (advisor)
The bachelor thesis deals with interactions between low-molecular and high-molecular weight hyaluronic acid (HA) and protonized amphiphilic amino acids Lysine and Arginine. The interactions were observed in the area of low aminoacids concentrations with in the range 0–15 mmoldm-3. The interactions occur between the carboxyl groups of HA and the amino group of the protonated amino acids. Proving these interactions would allow us to physically modify HA and further more, use such a system as a carrier of pharmaceuticals. The resistence towards the ionic strength at the concentration of 0,015 and 0,15 moldm-3 NaCl was investigated. Previous results show that the system with unprotonated amino acids at low concetrations of electrolyte in the solution is rather disturbing. Therefore, the interactions were reinforced by the aminoacids protonation using HCl. The amino acids were protonated not only completely, but also partly because of negative influence of chloride anions. To study the interactions pH-metry, conductance and Dynamic Light Scattering were used.
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Hydrodynamic properties of hyaluronan-lysin systems
Kunert, Vojtěch ; Kratochvílová, Romana (referee) ; Chytil, Martin (advisor)
This bachelor’s thesis studies the interactions of hyaluronan with partly protonized amino acids lysine and arginine. Rheology and viscosimetry were used to analyze the interactions. pH-metry and conductance measurements were used to check the interactions. Individual mixtures were measured and the data was compared to each other, but also in terms of partly and complete protonization. The interactions have been observed in all selected concentrations.
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Hyaluronan-amino acids interactions
Jugl, Adam ; Maršálek, Roman (referee) ; Mráček, Aleš (referee) ; Pekař, Miloslav (advisor)
The presented dissertation focuses on non-covalent interactions of hyaluronan of different molecular weights (9–1540 kDa) with basic (oligo)-amino acids (especially arginine) and the antimicrobial peptide cecropin B. High-resolution ultrasonic spectroscopy (HR-US), isothermal titration calorimetry (ITC) and potentiometric titration techniques were chosen to investigate the interactions. The thesis focuses on the characterization of interactions, especially with respect to the used molecular weight of interacting polymers and the ionic strength of the environment. Whether interactions occur or not was determined primarily by the length of the arginine oligomer chain. For monomeric amino acids, the interactions were investigated mainly by potentiometric titrations. Interactions were observable from arginine oligomers with eight monomer units. The molecular weight of hyaluronan mainly affected the intensity of the interactions. The transition between the individual conformations of hyaluronan (rod and random coil) was especially significant. Investigation of interactions was performed in water, in solutions with different concentrations of sodium chloride and in PBS. The sufficiently high ionic strength of the solution was able to suppress the interactions in water between the oligomers of arginine and hyaluronan. The basic antimicrobial peptide cecropin B has been shown to interact with hyaluronan in water but not in PBS. Based on these results, it was possible to conclude that the hyaluronan-cecropin B system would be particularly suitable for topical applications.
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Adsorption of AOM amino acids onto activated carbon
Čermáková, Lenka ; Pivokonský, Martin (advisor) ; Benešová, Libuše (referee)
This diploma thesis deals with the efficiency and factors affecting the adsorption of AOM (Algal Organic Matter) amino acids (AAs) arginine (Arg), phenylalanine (Phe) and aspartic acid (Asp) onto granular activated carbon (GAC) Picabiol 12x40 (PIC). The efficiency of AOM AAs removal was studied in laboratory equilibrium and kinetic experiments and it was shown that the adsorption efficiency of the selected AAs is dependent on the structure of the molecule of AAs and the nature of the functional groups of their side chain, and more particularly to solution pH, which determines the nature and size and surface charge of AAs and GAC. In contrast to this, the ionic strength (IS) of solution had relatively low effect on the AAs adsorption. Arg adsorption efficiency increased with increasing pH and reached a maximum at pH 9, where AAs and GAC were oppositely charged, and this leads to attractive electrostatic interactions. In the case of Asp adsorption on PIC practically did not work. The reason is that under all experimental conditions Asp molecules and the surface of the PIC carried identical negative charge. This led to the strong electrostatic repulsion between Asp and PIC which prevented effective adsorption. In the case of Phe the adsorption decreases with increasing pH. Maximum adsorption...
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Study of interactions of hyaluronan-amino acids
Jugl, Adam ; Smilek, Jiří (referee) ; Hurčíková, Andrea (advisor)
The master´s thesis deals with the study of the interaction between the polysaccharide hyaluronan of diffrerent molecular weights with the amino acids arginine, lysine, arginine hydrochloride and 6-aminocaproic acid. They are expected interaction between carboxyl groups of hyaluronan and amino groups of amino acids. These interactions were investigated by using ultrasonic spectroscopy, DLS, measuring pH and conductivity. Obtained results were compared with sodium polystyrene sulfonate. With ultrasonic spectroscopy was observed a change of concentration inkrement for titration of amino acid to water or polymers solutions especially for high molecular weight hyaluronan and for NaPSS in combination with 6AKK in concentration range of added amino acid 0–30 mM. The size of this change could mean a degree of interaction between polymers and amino acids. This theory has not been confirmed by other methods. By pH and conductivity measurements interations between arginine and low molecular weight hyaluronan and NaPSS were only confirmed. There was no possibility to make unequivocal conclusions from determination of particle size and zeta potential by DLS. Overall, the issue of the interaction of amino acids with polyanions was proved above expectations complex and will be appropriate to further expand the observations made in this thesis.
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Hydrodynamic properties of hyaluronan-lysin systems
Kunert, Vojtěch ; Kratochvílová, Romana (referee) ; Chytil, Martin (advisor)
This bachelor’s thesis studies the interactions of hyaluronan with partly protonized amino acids lysine and arginine. Rheology and viscosimetry were used to analyze the interactions. pH-metry and conductance measurements were used to check the interactions. Individual mixtures were measured and the data was compared to each other, but also in terms of partly and complete protonization. The interactions have been observed in all selected concentrations.
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Dynamic light scattering and electroanalytical investigation of hyaluronan-amino acids systems
Muchová, Johana ; Kalina, Michal (referee) ; Chytil, Martin (advisor)
The bachelor thesis deals with interactions between low-molecular and high-molecular weight hyaluronic acid (HA) and protonized amphiphilic amino acids Lysine and Arginine. The interactions were observed in the area of low aminoacids concentrations with in the range 0–15 mmoldm-3. The interactions occur between the carboxyl groups of HA and the amino group of the protonated amino acids. Proving these interactions would allow us to physically modify HA and further more, use such a system as a carrier of pharmaceuticals. The resistence towards the ionic strength at the concentration of 0,015 and 0,15 moldm-3 NaCl was investigated. Previous results show that the system with unprotonated amino acids at low concetrations of electrolyte in the solution is rather disturbing. Therefore, the interactions were reinforced by the aminoacids protonation using HCl. The amino acids were protonated not only completely, but also partly because of negative influence of chloride anions. To study the interactions pH-metry, conductance and Dynamic Light Scattering were used.
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