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Complexes of 1,4,7-triazacyclononane phosphinate derivatives
Lebruška, Viktor ; Kubíček, Vojtěch (advisor) ; Štěpnička, Petr (referee)
Phosphorus pendant arms accelerate the complexation of gallium(III) ions with macrocyclic chelators, which is crucial parameter in labelling by the radioisotope 68 Ga and their use in positron emission tomography (PET). In this thesis, new chelators for the selective complexation of gallium(III) ions were designed. Two chelators derived from the TACN macrocycle were prepared, namely: 1,4,7-triazacyclononane-1-methyl-methylene- bis(phosphinic) acid (H2L1 ) and 1,4,7-triazacyclononane-1-methyl-methylene- bis(phosphinato)-4,7-bis(methyl-phosphinic) (H4L2 ). The acidobase properties of the H2L1 were investigated using potentiometric and NMR titrations. Complexes of H2L1 with Ni(II), Cu(II), Zn(II) and Ga(III) were investigated using potentiometric titrations, which showed the high stability of these complexes. The solid-state structures of the Cu-L1 and Zn-L1 complexes were determined by X-ray diffraction. Complexation of the radioisotope 68 Ga(III) was studied for chelators H2L1 , H4L2 and for several related chelators with phosphorus pendant arms. The complexation study showed that chelators with the methylene-bis(phosphinate) pendant arm and some other phosphorus chelators derived from the TACN macrocycle accelerate complexation of gallium(III) ions. Using Dynamic PET scanning and ex-vivo...
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Ternary macrocyclic complexes of metals with fluoride anions
Kuncová, Lucie ; Kubíček, Vojtěch (advisor) ; Schulz, Jiří (referee)
The aim of this thesis was to synthesize three ligands derived from mackrocycle TACN, which were previously investigated in our laboratory group, and subsequently prepare gallium and aluminum complexes with these ligands for the study of coordination properties. The complexes were characterized by NMR, HPLC-MS and EA. For the complexes that were prepared, data on the ability to bind fluoride anions (i.e. the formation of ternary macrocyclic complexes) were measured using fluoride ion-selective electrode. Dissociation equilibria at pH = 8-10 were also studied for the complex [Ga(L1)] that had the highest percentage of bound fluorine anions (~ 95%).
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Dimer macrocyclic complexes
Rys, Jan ; Kubíček, Vojtěch (advisor) ; Vojtíšek, Pavel (referee)
This thesis is focused on dimer macrocyclic ligands and their complexes. Two dimer macrocyclic ligands based on ligand DO3A, linked with xylyl linker were prepared (BDO3A-p-X a BDO3A-m-X). Both synthetized ligands were characterized using NMR, MS, EA and in the case of BDO3A-p-X by X-ray crystallography. Data for calculating pseudo-first order reaction rates for complexations with Ce3+ metal ion and their pH dependency were obtained by use of UV/VIS spectrophotometry. Obtained data were compared to structurally close monomer ligand BnDO3A. Dimer ligands display different coordination properties based on proximity and position of coordinating cavities. Both prepared ligands behave differently than structurally close monomer ligand BnDO3A.
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Nanofiber membranes with encapsulated photoactive molecules simultaneously generating NO and 1O2 species
Liška, Vojtěch ; Mosinger, Jiří (advisor) ; Kubíček, Vojtěch (referee)
This thesis focuses on the preparation and study of a new type of photoactive polycaprolactone nanofibrous membrane with encapsulated NO photodonor 4-(N- (aminopropyl)-3-(trifluoromethyl)-4-nitrobenzenamine)-7-nitrobenzofurazan and photosensitizer chlorin e6. The electrospun nanofibrous membrane exhibits efficient photogeneration of NO and singlet oxygen molecules, which initiate facial and space photoantibacterial properties. The structure of the prepared NO photodonor was studied by NMR spectroscopy and UV-VIS absorption spectroscopy measurements. The resulting nanofibrous material was studied by scanning electron microscopy, and the successful encapsulation of both photoactive species was studied by absorption and fluorescence spectroscopy. Photogeneration of the NO molecule was studied by direct amperometric detection of NO and by reaction with a chemical substrate. The photogeneration of singlet oxygen O2( Δg 1 ) was studied by time-resolved spectroscopy and by reaction with a chemical substrate. Significant photoantibacterial properties were demonstrated on the bacterial strain Escherichia coli DH5α. Both antibacterial effects were studied by monitoring the number of colony forming units (CFU) using image analysis, and the facial effect by scanning electron microscopy. Keywords: singlet...
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Modelling of quantum dynamics in anharmonic potentials using model of interacting harmonic oscillators.
Kubíček, Václav ; Čížek, Martin (advisor) ; Houfek, Karel (referee)
Thematically, the work pursues a means of numerical description of anhar- monic molecular vibrations regarding vibronic coupling. The main concern is with the possibility of replacing motion in adiabatic anharmonic potential with a set of vibroni- cally interacting harmonic potentials. The work initially provides an accurately tested implementation of a numerical method for finding stationary states in anharmonic po- tentials. And mainly, there is included a thorough discussion of how well the spectrum and states of the vibranically coupled model correspond to the adiabatic approximation of the same model. 1
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HPLC of Bioactive Compounds
Lukšanová, Aneta ; Kubíček, Vladimír (advisor) ; Lázníčková, Alice (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Biophysics and Physical Chemistry Consultant: Ing. Vladimír Kubíček, CSc. Student: Aneta Lukšanová Title of thesis: HPLC of bioactive compounds This diploma thesis is focused on finding conditions of HPLC analysis of midazolam and it's two metabolites - 1-hydroxymidazolam and 4-hydroxymidazolam, on method validation and on finding an appropriate internal standard. The analysis was carried out under reversed-phase conditions, the chosen column was POROSHELL 120 EC-C18, 3.0 X 100 NM, 2.7 µm, and a mixture of acetonitrile and ammonium acetate buffer with pH 4.5 in a ratio of 35/65 has been proven to be effective mobile phase. Detection was carried out using the diode array detector with wavelength values 223 nm and 272 nm. The column was thermostated at 25 řC, the analysis time was 10 minutes. Flow rate of mobile phase was 0.700 ml/min. Diazepam was found as a suitable internal standard. The method was validated only for 1-hydroxymidazolam and 4-hydroxymidazolam determination in rat plasma due to a submitter's request. Within the analytic method validation the following parameters were tested: precision, accuracy, lower limit of quantitation, linearity and selectivity.
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Oxidation of a psychoactive substance fluoromethoxyacetyl fentanyl
Krejčí, Michaela ; Kubíček, Vladimír (advisor) ; Nováková, Veronika (referee)
7 2. ABSTRACT Fluoromethoxyacetyl fentanyl (FMAcF) is a new psychoactive substance that belongs to the group of newly illegally synthesized fentanyl derivatives that have been entering the European drug market since 2009. The aim was to define the electrochemical behavior of FMAcF and to suggest possible oxidation mechanisms. In this research, the electrochemical methods and in situ UV-Vis spectroelectrochemistry were used to study drug oxidation and reduction mechanism. Electrochemical techniques were combined with high performance liquid chromatography with diode array detector. FMAcF in the aqueous medium provided a single oxidation peak whose potential depended on pH. The substance was not reduced under the studied conditions. UV-Vis spectroelectrochemistry showed the formation of a reaction intermediate. The substance was electrolyzed and the UV-Vis absorption spectra of the products were determined. The oxidation mechanism of the substance has been proposed. In future the incubation with liver microsomes will be performed to detect metabolic pathways. Key words: Cyclic voltammetry, Oxidation, Bioactive substance, Fentanyls, Fluoromethoxyacetyl fentanyl
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Influence of Electrolytes on CMC
Šmerdová, Jana ; Kubíček, Vladimír (advisor) ; Lázníčková, Alice (referee)
Souhrn V této diplomové práci bylo použito UV-VIS absorpční spektrofotometrie k měření CMC katonických tenzidů a vlivu elektrolytů na CMC. Dosažené výsledky potvrzují očekávaný trend poklesu hodnot CMC tenzidů se stoupající iontovou silou roztoků. Použitá modifikace metody UV-VIS absorpční spektrofotometrie pro stanovení CMC byla rovněž úspěšná.
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Study of radiolabelling of receptor-specific peptide from the group of gastrin derivatives I
Zeithamová, Jana ; Lázníčková, Alice (advisor) ; Kubíček, Vladimír (referee)
This work studies the radiolabeling of minigastrins using 111 In. For experimental purposes minigastrins 46, 47 and 48 were used with different amino acids sequences. It was made especially for radiochemical purity 111 InCl3 sign, since this parameter is very important for possible future use of these labeled peptides. Another parameter investigated was the monitoring of the stability of radioactively labeled minigastrins. Results were measured using high performance liquid chromatography, the clear evidence of pollution and possible degradation products. The second applied method was performed by instant thin-layer chromatography in several different environments. The objective was to determine the dependence on the purity of the product over time in both short and long time intervals.
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