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Optimizing the determination of distribution of surfactant at phase separation in polymer-surfactant system
Sátorová, Kateřina ; Pekař, Miloslav (referee) ; Mravec, Filip (advisor)
This diploma thesis is focused on the determination of distribution a surfactant at phase separation in polymer-surfactant system. Sodium hyaluronate of three molecular weights was chosen as a polymer, CTAB was used as a surfactant. The experiments were performed in an environment of 0,15 M NaCl. The measurement of the CTAB concentration in samples was based on the formation of coloured complexes of CTAB and picric acid in chloroform. UV-VIS spectroscopy was used for the detection of these complexes. The content of CTAB was determined in four gels of different composition (2% Hya + 200 mM CTAB, 2 % Hya + 50 mM CTAB, 0,5 % Hya + 200 mM CTAB, 0,5 % Hya + 50 mM CTAB). All gels were gradually washed five times with 0,15 M NaCl. The content of CTAB was determined for newly prepared gels and for gels after 2 and 4 months since the preparation. Initial concentrations of CTAB and hyaluronan have greater influence on the distribution of CTAB after phase separation, than the molecular weight of hyaluronan. The content of CTAB in newly prepared gels and after 4 months since preparation is very similar and demonstrates the stability of the system.
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Encapsulation of natural antioxidants
Štindlová, Jitka ; Obruča, Stanislav (referee) ; Márová, Ivana (advisor)
In theoretical part of this diploma thesis the basic properties of antioxidants, especially anthocyanins and phenolic compounds are described, as well as the basic features and principles of free radicals formation. The theoretical part also describes some possible ways of encapsulation of antioxidants into polysaccharide and lipid particles. In the experimental part basic characteristics of extracts from selected lyophilized fruits and vegetables (carrots, apples and mixed berries) are described. As group parameters of plant extracts the total antioxidant activity, content of flavonoids and phenolics, carotenoids, anthocyanins and ascorbic acid were determined. In experimental part also various encapsulation techniques were tested, encapsulation effectiveness of each technique was evaluated and the stability and size of the created particles were determined. As the best encapsulation method in terms of encapsulation efficiency in most of samples/parameters ethanol injection was found. On the other hand the particles prepared by ethanol injection are relatively unstable in terms of zeta potential, which is followed by their tendency to aggregate. As the most stable particles prepared by thin layer evaporation (TLE) and reverse phase thin layer evaporation (RP-TLE) were evaluated. Particles prepared by TLE, RP-TLE and chitosan-alginate particles exhibited a negative charge, while particles prepared by ethanol injection stayed uncharged and chitosan particles have a positive charge.
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The chitosan-glucan complex isolated from Schizophyllum commune
Krčmář, Martin ; Obruča, Stanislav (referee) ; Omelková, Jiřina (advisor)
Chitosan-glucan complex is fungal origin copolymer that finds application in medicine and cosmetics. Traditionally mycelium of Aspergillus and Penicillium is considered as industrial chitosan-glucan complex source, though utilization of Micromycetes in biotechnological productions is sometimes undesirable. The aim of the work was to study the possibility of Basidiomycete Schizophyllum commune submerged cultivation for industrial scale chitosan-glucan complex production use. Within the work there was studied effect of cultivation conditions (type and concentration of carbon sources in nutrient medium, ratio of carbon source to nitrogen source, medium initial pH and aeration intensity) on Sch. commune #127 mycelium growth, chitosan-glucan complex formation and exopolysaccharide synthesis. As the result, the method for chitosan-glucan complex production increase and exopolysaccharide synthesis suppression was suggested. Chitosan-glucan complex from Sch. commune #127 submerged mycelium was separated by successive alkali and acid treatments. Effects of alkali concentration and application technique, and type of acid on physical and chemical properties of chitosan-glucan complex were described. Analytical methods for in process control and final product characteristics were suggested.
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Synthesis of core/shell quantum dots for diagnostic
Mihajlovic, A.
In this paper, synthesis of colloidal core and core/shell quantum dots (QDs) was described. First, CdTe QDs capped with glutathione, thioglycolic or mercaptopropionic acid were prepared in aqueous phase, and used for synthesis of colloidal core/shell CdTe/ZnS QDs. Core/shell QDs were used for conjugation with bovine serum albumin (BSA) or immunoglobulin G (IgG) via different crosslinkers (CDI, EDC/NHS, EDC). QDs as well as QDs-protein/antibody conjugates were characterized via UV-Vis spectroscopy and capillary electrophoresis (CE). Based on UV-Vis spectroscopy results it was found that, with increasing concentration of BSA, fluorescence intensity of QDs decreased. CE confirmed formation of QDs-BSA and QDs-IgG conjugates.
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Nanostructures produced by conducting polymer, polyaniline
Konyushenko, Elena ; Stejskal, Jaroslav (advisor) ; Vohlídal, Jiří (referee) ; Žigon, Majda (referee)
Charles University in Prague Faculty of Science Department of Physical and Macromolecular Chemistry Institute of Macromolecular Chemistry Academy of Sciences of the Czech Republic Nanostructures produced by conducting polymer, polyaniline Abstract of the Doctoral Thesis Elena Konyushenko Supervisor: Jaroslav Stejskal, PhD. Prague 2008 Univerzita Karlova v Praze Přírodovědecká fakulta Katedra fyzikální a makromolekulární chemie Ústav makromolekulární chemie Akademie věd České republiky, v.v.i. Nanostruktury vytvářené vodivým polymerem, polyanilinem Autoreferát disertační práce Ing. Elena Konyushenko Školitel: RNDr. Jaroslav Stejskal, CSc. Praha 2008 Contents 1. The aims of the Thesis 5 2. Preparation of polyaniline 6 3. Polymerization of aniline in the solutions of weak acids 7 4. Oxidation of aniline in alkaline media 8 5. Supramolecular morphology of polyaniline 9 6. Preparation of composites of carbon nanotubes and polyaniline 15 6.1. Carbon nanotubes coated by polyaniline 15 6.2. Properties of the composites 15 7. Carbon nanotubes with nickel catalyst nanoparticles coated by polyaniline 16 Abstract (in Czech) 18 References 19 List of papers 21 4 List of papers 1. Konyushenko EN, Stejskal J, Šeděnková I, Trchová M, Sapurina I, Cieslar M, Proke J, Polyaniline nanotubes: conditions of formation, POLYMER...
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Význam glutathionu pro kvalitu hroznů a vína
Kandourova, Alexandra
Glutathione is an important constituent of grape, must, and wine. Special emphasis is given to its occurrence in grapes, must, and wine; its role as an antioxidant in wine. The effect of glutathione on aroma compounds is also outlined. There are information on the positive effects of the use of glutathione-enriched preparations in wine industry. It is evaluated its effectiveness in combination with ascorbic acid against oxidative color formation.
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Monitoring antiplatelet therapy in kardiology patients.
Colová, Martina ; Jílek, Petr (advisor) ; Trejtnar, František (referee)
1 ABSTRAKT Tato bakalářská práce se zabývá sledováním antiagregační léčby u kardiologických pacientů. Teoretická část této práce popisuje vznik primární hemostatické zátky, typy antiagregační léčby, příčiny rezistence antiagregační léčby. Vyhodnocuje výsledky optického a impedančního měření agregace trombocytů a účinnosti antiagregační léčby. Sledovaný soubor zahrnuje měření 94 pacientů. Klíčová slova: hemostáza - agregace trombocytů - antiagregační léčba - kyselina acetylsalicylová - clopidogrel ABSTRACT This thesis deals with the monitoring of antiplatelet therapy for cardiac patients. The theoretical part of this work describes the primary haemostatic plug formation, types of antiplatelet therapy, antiplatelet therapy causes resistance. Evaluates the results of optical and impedance measurements of platelet aggregation and the effectiveness of antiplatelet therapy. The observed set of measurements includes 94 patients. Keywords: hemostasis - platelet aggregation - antiplatelet therapy - acetylsalicylic acid - clopidogrel
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Spectroelectrochemical cell with CD-trode
Hladík, Martin ; Nesměrák, Karel (advisor) ; Rychlovský, Petr (referee)
This bachelor thesis was aimed on the optimisation of preparation of gold electrodes (CDtrodes) from commercially available DVDs by treatment of concentrated nitric acid. The duration of the treatment was set on 20 minutes, based on study of voltammetric responses of fabricated CDtrodes. The CDtrodes were employed in spectroelectrochemical cells in two arrangements (i) with beam perpendicular to the area of electrode, and (ii) with beam collinear to the area of electrode. The formation and extinction of phenothiazine radicals during cyclic voltammetry were followed spectrophotometrically. Key words: spectroelectrochemistry, CDtrode, phenothiazine
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The design and synthesis of selective copper(II) chelators
Havlík, Jan ; Kotek, Jan (advisor) ; Holzhauser, Petr (referee)
Title: Design and synthesis of selective copper(II) chelators Author: Jan Havlík Department: Department of Inorganic Chemistry, Faculty of Science Supervisor: assoc. prof. RNDr. Jan Kotek, Ph.D. Supervisor's e-mail address: modrej@natur.cuni.cz The aim of this work was to prepare selective copper(II) chelators. Within the frame of this thesis were synthesized 13 compounds, from which 7 are new. All compounds were fully characterized by NMR spectroscopy and mass spectrometry. Copper(II) complex of synthesized ligand 1,11-bis(methylphosphinic acid)cyclam, (1,11-dipin), was studied in thermodynamic and formation/decomplexation studies. For 1,11-dipin-copper(II) complex were determined values of rate constants and activation parameters. Keywords: selective chelator, copper, cyclam derivatives, macrocyclic ligands, methylphosphonate, methylphosphinate
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The influence of intravenously administeres lactoferrin in early phase of coronnary thrombosis - histopathological analysis
Škrle, Jan ; Semecký, Vladimír (advisor) ; Mladěnka, Přemysl (referee)
Lactoferin (La) is an 80-kDa iron-binding glykoprotein. It shares a high degree of homology at amino acid sequence level and also the three dimensional conformation level with transferin. Afinity of Lf to iron is about 260times higher than that of transferin. Lf is present physiologically in exocrine secretions, eg.: tears, saliva, milk, sinovial fluid, seminal fluid and in the secondary granules of neutophils. The precise function of Lf in organism is considered to be very complex and is still a hot subject of scientific disputation. Lf was documented to act as antimicrobial, antiinflamatory and antitumoral agent. These effects are probably based on its iron chelating properties. Similarly La inhibits hydroxyl radical formation via Fenton reaction due to chelation of free iron. The catecholamine model of myocardial injury, represented by administration of synthetic catecholamine isoprenaline (ISO), posseses many pathophysiological similarities with acute myocardial infarction (AMI). The only possibility for myocardial tissue recovery in AMI represents the reperfusion of ischaemic myocardium. But this process is associated with tissue derangement due to burst of hydroxyl radical catalyzed by free iron (Fenton reaction). Therefore La has been proposed to have potentially positive effects in a catecholamine...
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