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Viscosimetry of hyaluronan-amphiphile systems
Trojan, Martin ; Běťák, Jiří (referee) ; Chytil, Martin (advisor)
This bachelor thesis investigates the interaction between the polysaccharide sodium hyaluronate (HA) and some amphiphilic molecules. As amphiphilic molecules the aminoacids lysine and 6 – aminocaproic acids were chosen. The presence of the carboxylic group on HA and the aminogroup on the aminoacids suggests electrostatic interaction between these two compounds. This supposal offers the possibility to modificate HA and uses it as a new type of a carrier of bioactive compounds, for example medicals. The HA of two molecular weights (1.75MDa and 70kDa) were chosen for the study of the interactions with the aminoacids. Solutions of HA and stock solutions of the aminoacids were prepared for their mutual mixing in the various volume ratios. The solutions and the mixtures were measured in three types of environment: pure water, 0.15M solution of NaCl and in phosphate buffer (PBS) of pH 6. The interactions were investigated by means of reometry. Our results show, the presence of interactions between HA and the aminoacids mainly in the system consisting the 1.75 MDa HA and lysine in water. As a result of the interactions, a decrease in the viscosity of the mixtures comparing to the HA solutions was observed.
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Viscometric study of L-Lysine- and 6-aminocaproic acid-hyaluronan systems behavior within the range of low aminoacids concentrations
Šimáčková, Marcela ; Běťák, Jiří (referee) ; Chytil, Martin (advisor)
This bachelor thesis investigates the interaction between high-molecular weight hyaluronic acid (1.75 MDa HA) and amino acids, particularly lysine and 6-aminocaproic acid. The interactions should occur between the carboxyl groups of HA carrying a negative charge and a positive charge located on the nitrogen atom of the protonated amino acids. The presence of these interactions would mean the possibility of establishing bioactive compounds, e.g. drugs, on hyaluronic acid, in which it would act as a targetting carrier. The interactions were examined at low concentrations for both aminoacids, i.e. below 10 mmoldm-3, and for 6-aminocaproic acid also at high aminoacid concentrations, i.e. above 20 mmoldm-3. The presence of interaction was investigated using not only rheology, but also by measuring pH and conductivity. Based on this research, the interactions manifested in terms of a decrease in the system viscosity.
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Investigation of Polyelectrolytes Interactions with Cationic Aminogroups-containing Amphiphiles
Zeman, Jan ; Běťák, Jiří (referee) ; Chytil, Martin (advisor)
The study deals with interactions of polyelectrolytes polystyrene sulfonate and hyaluronic acid with nitrogenic amphiphilic substances, represented by lysine and albumine. To study the interactions pH-metry, conductance, viscositic and turbidity measurement, DLS and reometry were used. All mixtures of different concentrations were measured and the data were compered with data obtained from measurement of samples with amphiphilic sumstances without polyelectrolytes. Observed interactions occured in the aminoacid concentrations between 0 to 20 mmoldm-3, then the PSS interaction groups were fully bonded by lysine and no more interactions were recognized. The same behaviour were observed in albumine solutions with concentration under 2 gdm-3.
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Study on interactions of protonated aminoacids with low-molecular weight hyaluronan
Chlumská, Jana ; Kalina, Michal (referee) ; Chytil, Martin (advisor)
This bachelor thesis deals with interactions between hyaluronic acid (HA) of low molecular weight (110-130 kDa) and protonated aminoacids lysine and 6-aminocaproic acid. For investigation of these interactions, methods such as pH-metry, conductance measurement, viscometry and dynamic light scattering were used. The electrostacic interactions between carboxylic group of HA and the aminogroup of the aminoacids are presumed. Proving these interactions would allow us to physically modify HA and further more, using such a system as a carrier of pharmaceuticals. The interactions of protonated lysine with HA were studied in pure water or in the solution of NaCl (c = 15 mmol•dm-3). Interactions of 6-aminocaproic acid were studied only in pure water. Both aminoacids were in the concentration range 0.9-20 mmol•dm-3. The decrease in the viscosity of the solutions indicates the interactions for lysine; for 6-aminocaproic acid the interactions also occured, but not as signifciantly as for the system containing lysine.
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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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Vliv příkrmu na porážkovou hmotnost a složení jatečného těla u faremně chovaných daňků (Dama dama)
FRIEDBERGEROVÁ, Eliška
This thesis "Effect of concentrates feeding on slaughter weight and carcass composition in farmed fallow deer (Dama dama)" evaluates the influence of two different sorts of complementary food and a nutritive supplement to slaughter weight and structure of a fatted body. The literature summary is complemented with results of the experiment conducted on The Mnich Farm near Kardašova Řečice in association with The Institute of Animal Science. Ten-month fallow deers were divided into three groups. Each of them was kept separately, one (the control group No.1) was fed only by pasture, the group No.2 and No.3 were fed by complementary food consisting of barley and oat in a ratio of 2/3:1/3 in the amount of 0,4 kg per one head and day. The group No. 3 was extra served by the nutritive supplement containing protected lysine. The animals were weighted at the beginning of the experiment and in the process of slaughter at the age of sixteen months. Fifteen heads of cattle were randomly chosen from every group and they were slaughtered during three days - five at a day from each of group. The animals were transported to the slaughterhouse afterwards where the slaughter preparation was done according to the JUT´s (The Slaughter Preparation of meat stock classification) and the SEUROP´s (The System of Slaughter Preparation of meat stock classification) rules. The differences were statistically compared. Beyond the task the economical evaluation of profitability of complementary food and nutritive supplement admixture to the feeding ration and the slaughter processing effectivity has been made.
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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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