National Repository of Grey Literature 18 records found  previous11 - 18  jump to record: Search took 0.00 seconds. 
Development of Novel Electrochemical Methods Using Various Membrane Materials for Monitoring of Selected Anticancer Drugs and Phytochelatins
Skalová, Štěpánka ; Barek, Jiří (advisor) ; Labuda, Ján (referee) ; Trnková, Libuše (referee)
Present Ph.D. Thesis is focused on the development of electrochemical methods for determination of anticancer drugs using various types of membranes for their preliminary separation. Furthermore, this Thesis reports the study of transport mechanisms of heavy metals in the presence of phytochelatins across biological membranes. Sodium anthraquinone-2-sulphonate (AQS) was used as a model compound for its similar structure with anthraquinone-based (AQ-based) anticancer drugs (doxo/daunorubicin) and also due to its better availability. All these compounds can be easily electrochemically oxidized and/or reduced. Redox behaviour of AQS was investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) in a cathodic region on mercury meniscus modified (m-AgSAE) and polished silver solid amalgam (p-AgSAE) electrodes, Obtained results were used for the development of a micro-volume voltammetric cell (MVVC). Its applicability for voltammetric determination of anticancer drugs was verified by using doxorubicin (DX) as a model substance. The second part of this Thesis deals with therapeutic monitoring of anticancer drugs in the blood circulation of the patients. For pilot experiments, a liquid-flow system with dialysis catheter and amperometric detection was used. The flow rate of carrier...
New Strategies in Electrochemical Detection of DNA Damage Induced by Interaction with UV radiation
Přibylová, Monika ; Vyskočil, Vlastimil (advisor) ; Fischer, Jan (referee)
V této bakalářské práci byl zkoumán netradiční redoxní indikátor 5-nitro-1,10-fenantrolin jako možný ukazatel poškození DNA. Měření probíhalo elektrochemicky technikou diferenční pulzní voltametrie v tříelektrodovém zapojení. Jako pracovní elektroda byla použita elektroda z ultračistého grafitu, která byla modifikována nízkomolekulární DNA z lososích spermií. Poškození DNA probíhalo pomocí UVC záření o vlnové délce 254 nm. Byl studován rozdíl výšky voltametrických signálů 5-nitro-1,10-fenantrolinu mezi nepoškozenou a poškozenou DNA. Nově vyvinuté metody se ukázaly jako slibné pro detekci míry poškození DNA v závislosti na čase ozařování a v závislosti na vzdálenosti od zdroje ozařování. Poškození DNA bylo rozsáhlejší u obou studovaných faktorů v závislosti na jejich rostoucích hodnotách. Klíčová slova Elektrochemie DNA biosenzory Netradiční elektrodové materiály Poškození DNA Biologicky aktivní látky Záření
Study of bioactive compounds of fennel
Mierna, Jana ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
The master´s thesis is focused on the study of biologically active compounds of fennel. The theoretical part describes basic characteristics of fennel and its chemical composition, further specifies plant´s biological active substances and antioxidants, also describes extraction techniques for obtaining these bioactive compounds, methods of their determination and verification of antimicrobial effect. In the experimental part were spectrophotometrically determined contents of polyphenols and flavonoids in the prepared extracts of fennel tea, whole and crush spice. On the basis of extraction curves, antioxidant activity and potential antimicrobial activity against the selected microorganisms Bacillus subtilis, Bacillus cereus, Serratia marcescens a Micrococcus luteus was determined in the samples with the highest values of the given bioactive substances. Among the all monitored extracts, the inhibitory effect was showed only by an aqueous extract of the fennel tea against the bacterial strain of Micrococcus luteus.
Determination of biologically active compounds in hops by LC/HR-MS method
Jandovská, Vladimíra ; Sobotníková, Jana (advisor) ; Spáčil, Zdeněk (referee)
This thesis describes development and optimalization of method for identification of polyphenols compounds present in hops (Humulus lupulus L.) that have potential antimicrobial activity. Within extraction of compounds from hop, minced hop cones were applied in a growth medium, where compounds diffused into the medium and created an inhibition zone after inoculated with Streptococcus aureus. The method combining extraction with acetone a salting out using QuEChERS principles was optimized for extraction of compounds from solid growth medium. The analysis was carried out using LC/HR-MS with a quadrupole-orbitrap hybrid mass analyzer. The MS method was developed as a screening method with a subsequent fragmentation of compound of interest on the base of inclusion mass list. The compounds extracted from inhibition zone were identified either by searching against a database or their structures have been elucidated on the basis of their fragmentation spectra.
Flavonoids and other biologically active compound in sea buckthorn
Michalíková, Adéla ; Hudeček, Jiří (advisor) ; Moserová, Michaela (referee)
This bachelor thesis summarizes information about sea buckthorn (Hippophae rhamnoides), about chemical composition of different parts and products based on this species, and about their biologically active contents. A special emphasis is given to the oil prepared from sea buckthorn fruits. Sea buckthorn is a rich source of antioxidants such as vitamin C, vitamin E, flavonoids and carotenoids. The oil contains high levels of unsaturated fatty acids, in particular of palmitooleic acid. The beneficial effects on human health make sea buckthorn and products from this plant popular food supplements. The second part of this thesis describes analytical methods used for determination of bioactive compounds in sea buckthorn.The protocols based on high performance liquid chromatography, gas chromatography or capillary electrophoresis are described in more detail. In the experimental part, four samples of sea buckthorn oil (two from Czech and two from Mongolian producers) were compared using absorption spectrophotometry and colorimetric evaluation using the CIELab method. Both samples of Czech origin displayed somewhat shifted absorption maxima and much weaker absorption, their coloration being much weaker. This may suggest some adulteration of these products Keywords: Sea buckthorn, Hippophae rhamnoides,...
Preparation of 3-phenylpentanoic and 3-phenylpent-2-enoic acid derivatives
Fatka, David ; Machara, Aleš (advisor) ; Veselý, Jan (referee)
This Bachelor's thesis deals with preparation of the intermediates of the analgesic tapentadol. The chosen synthetic strategy requires a preparation of appropriate derivatives of 3-phenylpentanoic and 3-phenylpent-2-enoic acid. Synthesis of those derivatives represents the cornerstone of the thesis. In the first part, the thesis describes an effort associated with a preparation of 1-[(3-benzyloxy)phenyl]propan-1-one, a necessary intermediate for the preparation of the titled compounds. Then addition reactions were studied on the aforementioned ketone. The second part of the thesis focuses on one particular addition, a Reformatsky reaction, and deals with further optimization. In addition, the submitted thesis also describes variety of attempts to carry out dehydration of the Reformatsky adducts, namely, benzylic tertiary alcohols. Powered by TCPDF (www.tcpdf.org)
The problems of interaction testing compounds in ecotoxicology.
Pavlíčková, Ivana ; Pavlovský, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
Bachelor thesis summarizes current knowledges of the problems of interaction of tested compounds and the determination of ecotoxicity. The work deals with the evaluation of ecotoxicity of binary mixtures of substances, toxic metals, or biologically active substances. The work is a brief summary of ecotoxicity tests used.
Characterization of active substances in several kinds of beer
Benešová, Pavla ; Obruča, Stanislav (referee) ; Márová, Ivana (advisor)
The aim of this bachelor thesis is to analyse biologically active compounds, especially of phenolic character, in 10 kinds of alcohol-free beer in comparison with alcoholic beer. In theoretical part basic steps of brewery technology are described including alcohol-free beer production. Characteristic compounds occurring especially in Czech beer e.g. proteins, phenolics, bitter substances and also methods for their analysis are discussed as well. Microfluidic electrophoresis (Experion, BioRad) was used to beer protein analysis. Phenolic compounds, flavonoids, technological characteristics and antioxidative activity were measured by spectophotometry. Individual phenolics of selected beers were identified and quantified by LC/ESI-MS analysis too. In alcohol-free beers similar concentrations of biologically active compounds were found in comparison with alcoholic beers, especially in the case of beer phenolics.

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