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Utilization of statistical approach in development of HPLC methods
Vymyslický, Filip ; Křížek, Tomáš (advisor) ; Kozlík, Petr (referee)
The aim of this diploma thesis was to develop a systematic procedure for the development of HPLC methods using the design of experiments. The system was developed based on the development of three HPLC methods for the determination of the purity of active substances using the design of experiments approach. The HPLC method for determining the purity of esomeprazole was selected to develop the systematic process for the development of HPLC methods by statistical approach. Experimental space was explored to find more suitable separation conditions. The second method used to develop the systematic procedure was the method for determining the purity of bisoprolol. This method was converted to a column of smaller size and the composition of the aqueous part of mobile phase was modified compared with the original pharmacopoeial method. Experimental space was explored to find more suitable separation conditions using the design of experiments. Last the method for determining the purity of risperidone was chosen. The composition of the aqueous part of mobile phase was changed in contrast to the original pharmacopoeial method. Experimental space was explored to find more suitable separation conditions using the design of experiments. For all studied HPLC methods, the values of the monitored chromatographic...
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Modification of carbon felt detector with copper microparticles
Baroch, Martin ; Dejmková, Hana (advisor) ; Schwarzová, Karolina (referee)
The first aim of this work was to develop copper modified carbon felt electrode for detection of amino acids, which are not electrochemically active on ordinary carbon electrodes. Phenylalanine solution at a concentration 1.0 mmol dm-3 was chosen as the testing solution. Electrode modified with electrochemical deposition of copper from mixture of copper(II) sulphate and sodium sulphate provided very low responses which were decreasing during first measurements, apparently because of insufficient amount of copper. Therefore, further experiments were performed using copper microparticles as a modifier. Copper microparticles activated in nitric acid at a concentration 80 mmol dm-3 were applied at carbon felt by several techniques and in different parts of the felt, i.e. by stirring the felt in microparticles suspension, by dripping of the suspension to the part of the felt in contact with capillary (proximal), between two parts of the carbon felt (sandwich) and at a part of the carbon felt in contact with electrolyte in a measuring cell (distal). Electrodes modified in the distal and in the sandwich arrangement were chosen as the best ones. In the last part, calibration dependences for phenylalanine in concentration range from 0.025 mmol dm-3 to 1.0 mmol dm-3 were measured on the last two electrodes....
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Content of biologically active phenolic compounds in cultivated of species of Vaccinium genus.
CARDOVÁ, Michaela
This bachelor´s thesis includes a knowledge about active biologic compounds from the most common grown species of cranberry (Vaccinium) in the Czech Republic. Active substances have been analyzed in varieties of Vaccinium vitis-idaea like Koralle, Runo bielawskie, Sanna, Sussi, Linnea and Ida. Polyphenols are biomolecules, which are founded in products of plants and there have been proved an antioxidant and anti-inflammatory effects in vivo and in vitro (Chiva-Blanch, 2017). In during of evolution, in plants evolved an ability to produce of secondary polyphenolic metabolites, which weren´t intervened to their growth and development but they are very important for environment, for reproduction strategy and mechanism of protection (Cheynier, 2013). Between polyphenols belong to for examples flavonoids and anthocyanins, which are co-pigment of their property. Next analyzed compound was vitamin C alias ascorbic acid. This substance is simple low-molecular-weight carbohydrate. Synthesis of vitamin C is localized of plants and some species of animal, (Lykkesfeldt, 2014). Ascorbic acid is a good antioxidant, which save organism before ROS (reactive oxygen form) and stimulated immune system. The aim of this study was analyzed the content of quercetin, ascorbic acid and the content of total anthocyanin in six selected varieties of cranberry. The determination as such was performed using high performance liquid chromatography (HPLC) and determination of content of anthocyanin were analyzed by use spectrophotometer for define concentration from absorbance of valid sample. We analyzed all of three mentioned kinds of compounds. The higher results of anthocyanin were analyzed from kind Sussi. Concentration was 617 ? 8.7 mg/kg. In kind of Sanna, the ascorbic acid amount to 110 ? 1.4 mg/kg and there were measured the content of quercetin 1019 ? 36 mg/kg in freeze-dryied material.
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In vitro saturation study of 99mTc-HYNIC-ramucirumab on PC-3 cell line
Lach, František ; Bárta, Pavel (advisor) ; Smutná, Lucie (referee)
v anglickom jazyku Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Student: František Lach Supervisor: Mgr. Pavel Bárta, PhD Consultant: Mgr. Lucie Hyršová Title of diploma thesis: In vitro saturation study of 99m Tc-HYNIC-ramucirumab on PC-3 cell line The number of malignant tumours in the population has increased in recent years. Due to the frequent serious sides effects of chemotherapeutic drugs on the whole organism, targeted antitumor therapy is at the forefront. Due to its specific effect on the regulatory and signal pathways of protein structures, monoclonal antibodies are used for the target anti-tumour therapy. The basic properties of the growing tumour include vasculogenesis (the ability to build new blood vessels from the endothelial precursors) and angiogenesis (the process of self-inducing formation of blood vessels). Endothelial tumour progenitors include vascular endothelial growth factor (VEGF). VEGF activates its biological activity by binding to its transmembrane tyrosine-kinase receptors VEGFR. Indeed, the inhibition of the vascular endothelial factor receptors is the target of some monoclonal antibodies. Ramucirumab is a monoclonal antibody that selectively inhibits VEGF receptor type 2 (VEGFR-2) and thereby...
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Voltammetric and Amperometric Determination of Nitrophenols Using Boron-Doped Diamond Film Electrode
Karaová, Jana ; Barek, Jiří (advisor) ; Šelešovská, Renáta (referee) ; Jaklová Dytrtová, Jana (referee)
Presented Ph.D. Thesis is focused on the use of the boron-doped diamond (BDD) electrodes for voltammetric and amperometric determination of selected nitrophenols: 2-nitrophenol (2NP), 4-nitrophenol (4NP), and 2,4-dinitrophenol (2,4DNP). These compounds are listed as "priority pollutants" by United States Environmental Protection Agency (US EPA) due to their negative impact on living organisms and are mainly used in agriculture as plant growth stimulators. BDD electrodes are used for determination of wide range of electrochemically both reducible and oxidisable organic compounds and have become a popular electrode material thanks to its commercial availability and excellent mechanical and electrochemical properties. A differential pulse voltammetric method was developed for the determination of 2NP, 4NP and 2,4DNP at a BDD film electrode using electrochemical reduction and of 4NP and 2,4DNP using electrochemical oxidation. The method was successfully applied for the direct determination of these compounds in drinking and river water in the concentration range from 4×10-7 to 2×10-5 mol.L-1 . To improve the limit of quantification, a preconcentration by solid phase extraction from 100 mL (drinking and river water) and 1000 mL (drinking water) of water samples was used with limit of determination...
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HPLC-ED/UV for determination of vanillylmandelic acid in human urine after solid phase extraction
Němečková-Makrlíková, Anna ; Dejmková, H. ; Navrátil, Tomáš ; Barek, J. ; Vyskočil, V.
HPLC with electrochemical and spectrophotometric detection (ED/UV) after solid phase extraction (SPE) was used for determination of vanillylmandelic acid in human urine. HPLC-ED was performed at a glassy carbon electrode in a “wall-jet” arrangement in acetate-phosphate buffer at pH = 2.5 and gradient elution (increasing content of\nacetonitrile from 5 to 25% in 10 minutes) was used. Optimized parameters were following: flow rate of mobile phase 1 mL min−1, detection potential +1.1 V, detection wavelength 279 nm, injected volume 20 μL. Dependence of the peak current on the analyte concentration was linear in the concentration range from 10 to 150 μmol L−1, with obtained limits of detection 2.6 μmol L−1 (calculated from peak height) and 1.9 μmol L−1 (calculated from peak area) for HPLC-ED, and 11.0 μmol L−1 (calculated from peak height) and 9.8 μmol L−1 (calculated from peak area) for HPLC-UV.
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HPLC Analysis of Drugs
Kouřil, Tomáš ; Kubíček, Vladimír (advisor) ; Drastík, Martin (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Tomas Kouril Consultant: Ing. Vladimir Kubicek, CSc. Title of Thesis: HPLC analysis of Drugs The diploma thesis describes selection of the most suitable conditions for determination of a two enantiomers of drugs betaxolol and bisoprolol with a method HPLC. The aim of the thesis was to find a suitable isocratic method for the substances for extraction from plasma. The chromatographic column Daicel Chiralcel ® OD-R 4,6 mm x 250 m was utilized. The best results were achieved with mobile phase consisting of acetonitrile and aqueous solution of sodium perchlorate (1 molar) in volume ratio 50:50 for betaxolol and 35:65 for bisoprolol. The column was thermostated at 25 řC. UV detection (λ = 190 nm) was applied to get a sufficient sensitivity. Tramadol and O-desmethyltramadol was tested as an internal standard. Biological samples were tested by LLE before the HPLC analyses. Furthermore, the LLE method for biological samples was tested before performing HPLC.
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Chromatographic characterization of an ion-exchange column
Seidlová, Bára ; Sobotníková, Jana (advisor) ; Křížek, Tomáš (referee)
The following evaluation procedure was selected for the charterized ion-exchange column Phenosphere™ SCX. First of all, a set of biologically interesting analytes was selected. This set contained several basic drugs, specifically five tricyclic antidepressants (TCA), an anesthetic called procaine and a substance with antimalaric and antiarrythmic effect - quinidine. For this set of basic substances were the separation conditions optimized on a characterized ion-exchange column Phenosphere™ SCX. The effect of the mobile phase composition on chromatographic behaviour of selected drugs was investigated, for instance the effect of used buffer and its concentration, buffer pH and the effect of addition of the organic modifier (in this case methanol). Under optimized chromatographic conditions for basic drugs analysis the ion-exchange column was characterized using LSER (Linear Solvation Energy Relationship). The chromatographic behaviour of the test substances with known molecular descriptors was found and then the multiple linear regression between retention factors of test substances and their molecular descriptors was done. The results of the multiple linear regression were discussed and then the interactions contributing to the analyte retention on the investigated cation-exchange column...
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Latitudinal trend in feather growth rates and steroid hormone concentrations in avian feathers
Brzobohatá, Tereza ; Albrecht, Tomáš (advisor) ; Sedláček, Ondřej (referee)
Avian life histories range along the axis from slow to fast, with slow life histories being characterized by greater investments in future reproduction, and fast by greater investments in current reproduction. The concept of pace-of-life syndromes refers to the coevolution of life strategies and related physiological, immunological and behavioral traits. Avian species from tropical areas are characterised by slower life histories (longer parental care, later maturation, smaller clutches, reduced metabolic rate) when compared to temperate zone species. Within this latitudinal gradient, investments in the total amount (weight) of body feathers have also been shown to be reduced in tropical birds. It remains unclear, however, whether feather growth itself follows this latitudinal pattern, and is slower in tropical species. Tropical birds have lower basal levels of corticosterone and testosterone, however available studies are based mainly on analyzes of hormone concentrations from plasma. The first aim of this diploma thesis was to evaluate differences between tropical (Cameroon) and temperate zone (the Czech Republic) passerine species in investments in tail feather growth by using methods of comparative ptilochronology. The second aim of the diploma thesis was to analyze concentrations of steroid...
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