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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.
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...
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...
Optimization of chromatographic parameters for chiral separation of biologically active compounds
Novák, Martin ; Kučera, Radim (advisor) ; Nobilis, Milan (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Chemistry and Pharmaceutical Analysis Student: Bc. Martin Novák Supervisor: doc. PharmDr. Radim Kučera, Ph.D. Consultant: Mgr. et Mgr. Rafael Doležal, Ph.D. Title of diploma thesis: Optimization of chromatographic parameters for chiral separation of biologically active compounds. The diploma thesis was focused on the development of a HPLC-UV method for the determination of K 1277 enantiomers of systematic name N-(2-((6-chloro-1,2,3,4-tetra- hydroacridin-9-yl)amino)hexyl-2-amino-3-(1H-indole-3-yl) propylamide dihydrochloride, which is one of the compounds from the tacrine-tryptophan hybrids group. These tacrine-tryptophan hybrids could be considered as promising candidates of potential drugs against Alzheimer's disease. The thesis brings an explanation of basic characteristic of chiral molecules, principles of chiral separation, pathophysiology, clinical manifestation and treatment of Alzheimer's disease and short characteristic of tacrine-tryptophan hybrids in the theoretical section. The aim of my diploma thesis was to find the optimal chromatographic conditions for separation of K 1277 enantiomers synthesized from tacrine and tryptophan fragments. The experimental part deals with the development of the chiral...
Extraction of nucleotides from plant matrix and their determination by ion-exchange high performance liquid chromatography
Konečná, Markéta ; Sobotníková, Jana (advisor) ; Coufal, Pavel (referee)
In this thesis chromatographic conditions for the HPLC analysis of ribonucleotides AMP, ADP and ATP were optimized. For their separation chromatographic column, Nucleogel SAX 1000-8, 50 x 4,6 mm, from the German company Marcherey-Nagel was used. The mobile phase of a 0,2 mol/L solution of KH2PO4, its pH was adjusted with 1mol/L with potassium hydroxide to pH = 5,00. As the most suitable flow rate was selected 1,0 mL/min. The analysis was conducted using an isocratic elution. Detection was conducted by a DAD detector at a wavelength of λ = 260 nm. Substances were eluted in the following order AMP (tr = 0,911 min), ADP (tr = 1,667 min) and ATP (tr = 7,262 min). The total analysis time of the mixture of standards, under the conditions mentioned above, lasted for 10 minutes. For the extraction of adenosine-5-ribonucloetides the real matrix frozen and lyophilized leaves of tobacco virginia (Nicotiana tabacum L.) have been used. Two methods of extraction were applied. The first procedure was based on the extraction of AMP, ADP and ATP from the leaves of the tobacco plant by boiling deionized water. In the second method 0,07 mol/L HClO4 for the extraction instead of deionized water was used. Keywords: HPLC, adenosine ribonucleotides, AMP, ADP, ATP, tobacco virginia
Analysis of biologically active substances by modern separation methods
Bierhanzl, Václav ; Čabala, Radomír (advisor) ; Pacáková, Věra (referee) ; Sýkora, David (referee)
The thesis is dedicated to the phospholipids and their polar headgroups analysis by gas chromatography, capillary electrophoresis and mass spectrometry. Phospholipids are the most important polar lipids and they are classified into phospholipid classes according to their phosphorylated groups. Phospholipids can be found in cell membranes and the changes in their ratio are monitored to research the impact of external conditions on cells. Actually thin layer chromatography is still used for phospholipid class ratio analyses. It is not suitable for microbiological research due to its time demandingness. The presented compendium of papers engaged in phospholipid classification is targeted on Bacillus subtilis strain, which produces potential antibiotics with detergent effect - surfactin. Published methods can be used for research of optimal conditions for producing microbe cultivation. Because non-polar parts of the phospholipid molecule (fatty acids) can affect the analysis methods on spliced polar headgroups have to be designed. Capillary electrophoresis and gas chromatography methods were developed and the latter one was further optimized for simultaneous analysis with fatty acids. Additional part deals with an alternative approach which consists in direct injection on mass spectrometer of intact...
Disposition of New Synthetic Drugs in The Organism. Pharmacokinetics and Biotransformation Study. Toxicological Detection in Biological Materials.
Židková, Monika ; Balíková, Marie (advisor) ; Šustková, Magdaléna (referee) ; Šanda, Miloslav (referee)
The object of this thesis was the study on the pharmacokinetics and biotransformation of selected abused new synthetic drugs, specifically belonging to cathinone and aminoindane groups, in experimental rats. This work consisted of two parts: a biotransformation study of mephedrone, methylone, 5,6-methylenedioxy-2- aminoindane (MDAI) and a distribution profile study of mephedrone, methylone, MDAI and naphyrone. This document is presented as a commentary to the original papers, which were published in peer reviewed journals. The samples of blood and tissue (brain, lungs, liver) were taken at specific times after a subcutaneous single bolus dose of the studied drugs. The urine samples for the biotransformation studies were collected over a 24-hour period following the sc. dose. The LC/HRMS method was used for metabolite detection and quantitative analysis. Our findings not only included testing metabolites of the aforementioneddrugs against the synthesized reference standards, but also discovering previously unknown metabolites of these drugs. Ten phase I and five phase II metabolites aside from the parent drug were identified in urine after mephedrone administration by comparison of their spectra against those of reference standards and/or MS2 spectra of previously identified metabolites. The main...
Carotenoids of snow algae as biomarkers for exobiology: Raman spectroscopic perspective
Němečková, Kateřina ; Jehlička, Jan (advisor) ; Němec, Ivan (referee)
The major aim of this thesis is critical evaluation of Raman spectroscopy in the detection of carotenoids of extremophiles, namely snow algae. Extremophilic microorganisms play an important role in exobiology since they set hypothetical boundaries for the presence of life on Earth. Raman spectroscopy will be a part of two mission to Mars. Here, a laboratory Raman microspectrometer was used for the analysis of 11 samples of snow algae from different locations over the years 2002-2017. The acquired spectra were compared with HPLC/UV-VIS analysis. The results showed that the ability of Raman spectroscopy to discriminate between structurally slightly differing carotenoid pigments or several carotenoids in an admixture is limited. Contrary, HPLC/UV-VIS permitted to detect various structurally similar carotenoids (and chlorophylls). However, HPLC/UV-VIS worked with overall pigment extracts during which some structural information can be lost. Raman microspectrometer allowed analysis of cells in different life-cycle stages and thus several various spectra could be studied. Raman microspectrometer was therefore more suitable for carotenoid detection in mixtures of various life-stages than HPLC/UV-VIS. Key words carotenoids, snow algae, exobiology, habitability, biomarker, Raman spectroscopy, HPLC/UV-VIS
Radiolabeling of ramucirumab followed with the study of its internalization in vitro
Gajdoš, Jakub ; Bárta, Pavel (advisor) ; Kuchařová, Monika (referee)
v anglickém jazyce Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Student: Bc. Jakub Gajdoš Supervisor: Mgr. Pavel Bárta, Ph.D. Title of diploma thesis: Radiolabeling of ramucirumab followed with the study of its internalization in vitro. The process of angiogenesis ensures the formation of the bloodstream at the site of its increased need. Therefore, it is not surprising that angiogenesis is often included in the tumor production process, because it provides the tumor cells nutrition supply and metabolite removal. The targeting of angiogenesis has become a key topic of some scientific research. The process of tumor blood supply formation provides a family of vascular endothelial factors (VEGFs) and their respective receptors, which have become the target of the angiogenesis attenuation in a cancer treatment. One of many therapeutics is the monoclonal antibody ramucirumab targeted against VEGF receptor type 2 (VEGFR-2). Radioactive labeling of ramucirumab with a suitable radionuclide could bring benefits in either radiotherapy or radiodiagnostics. The aim of this diploma thesis was the indirect radioactive labeling of monoclonal antibody ramucirumab using 99m Tc as radiodiagnostic nuclide via the chelation agent succinimidyl-6-...
In vitro saturation study of 99mTc-HYNIC-ramucirumab on PC-3 cell line
Lach, František ; Bárta, Pavel (advisor) ; Hyršová, 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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