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Analyses of Statins in Biological Samples
Vlčková, Hana ; Solich, Petr (advisor) ; Nobilis, Milan (referee) ; Šimek, Petr (referee)
5 ABSTRACT Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of analytical chemistry Candidate: Mgr. Hana Vlčková Supervisor: Prof. RNDr. Petr Solich, CSc. Supervisor specialist: Assoc. Prof. PharmDr. Lucie Nováková, Ph.D. Title of Doctoral Thesis: Analysis of statins in biological samples The doctoral thesis deals with analysis of statins in biological samples. Statins are the most widely used drugs for the treatment of Familiar hypercholesterolemia. Due to very low concentration of statins (ng/ml) in human plasma a choice of suitable analytical methods is limited. Liquid chromatography with mass spectrometry detection is the most suitable technique due to high selectivity and sensitivity. Sample preparation step has to be used before chromatographic determination of analytes in complex matrices, such as biological samples. Primarily theoretical part of doctoral thesis summarizes individual pharmacological properties and effects of statins. Another part is devoted to theoretical knowledge of UHPLC-MS/MS. The widest section deals with description of the individual sample preparation techniques. The practical part contends with development of UHPLC-MS/MS methods for the determination of statins in biological samples and selection and development of suitable sample preparation...
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Quantitative Measurement of Drugs in Biological Samples using Chromatography Methods.
Maláková, Jana ; Nobilis, Milan (advisor) ; Polášek, Miroslav (referee) ; Chládek, Jaroslav (referee)
Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of Pharmaceutical Chemistry and Drug Control Candidate: PharmDr. Jana Maláková Supervisor: Doc. PharmDr. Milan Nobilis, PhD., Associate Professor of Bioorganic Chemistry. Title of Doctoral Thesis: Quantitative measurement of drugs in biological samples using chromatography methods. The thesis deals with the application of instrumental analytical methods to the quantitative measurement of drugs and their metabolites in biological samples using liquid and gas chromatography. Various procedures of sample preparation were evaluated during optimization of analytical assays. Precipitation of proteins with acetonitrile was employed (analysis of cefuroxime), liquid-liquid extraction (analysis of topiramate, 8-methoxypsoralen) and samples were also purified using a mixed-mode solid-phase extraction (reversed-phase and ion-exchange principle) during the analysis of galantamine and its metabolites. The unbound cephuroxime fraction in the plasma and protein binding were determined using an ultrafiltration method. Chromatography conditions - gas or liquid chromatography- depended on physico-chemical characteristics of a drug. Due to the thermal decomposition of topiramate, derivatization was used to form a more stable methyl...
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Analysis of Biologically Active Compounds by Capillary Electrophoresis
Petrů, Klára ; Polášek, Miroslav (advisor) ; Nobilis, Milan (referee) ; Urbánek, Marek (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate Mgr. Klára Petrů Supervisor Doc. RNDr. Miroslav Polášek, CSc. Title of Doctoral Thesis Analysis of biologically active compounds by capillary electrophoresis The thesis presented is dealing with the analysis of quaternary ammonium compounds of pharmaceutical importance by capillary electrophoresis (CE). Basic principles of CE and respective means of detection are discussed in the theoretical part. Special attention is paid to capacitively coupled contactless conductivity detection C4D and to the CE coupling with mass spectrometry (CE-MS). The chemical and pharmacological properties of the compounds of interest: carbethopendecinium bromide, pancuronium bromide (PM), vecuronium bromide (VM) and rocuronium bromide (RM) are characterized. The experimental work is focused on the development and validation of new analytical CE methods for the assay of such compounds. in pharmaceuticals. The C4D detection was applied because of poor UV adsorption capability of all compounds studied. I. The first part deals with the CE analysis of septonex, an antiseptic drug with the character of surfactant. The background electrolyte was 30 mM MES of pH 7 containing 12.5 mg/ml of 2-hydroxypropyl-β-...
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Modern Trends in Sample Preparation of Biological Material for Analysis of Selected Biologically Active Compounds
Sadílek, Petr ; Solich, Petr (advisor) ; Nobilis, Milan (referee) ; Barták, Petr (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Petr Sadílek, M.Sc. Supervisor: Prof. RNDr. Petr Solich, CSc. Co-supervisor: Doc. RNDr. Dalibor Šatínský, Ph.D. Title of Doctoral Thesis: Modern Trends in Sample Preparation of Biological Material for Analysis of Selected Biologically Active Compounds This doctoral thesis deals with the determination of selected drugs, their metabolites and other biologically active substances in biological materials. This area of instrumental analysis turns out to be very attractive recently. The reason for this is the need to monitor and optimise treatment and the goal is to achieve the most effective therapy with minimum side effects of drugs for every individual; there are also toxicological reasons. The thesis concentrates on the entire analytical phase of laboratory screening, i.e. not just on development and validation of chromatographical methods of analysis, but also (and especially) on preparation of biological samples prior to the actual analysis. This phase is crucial for analytes assessment, since it determines not only correct results of the laboratory examination, but also influences the lifespan of laboratory equipment, especially chromatographic columns. These days mostly traditional...
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Transdermal Permeation Enhancers: Study of Structure-activity Relationships.
Novotný, Michal ; Vávrová, Kateřina (advisor) ; Nobilis, Milan (referee) ; Rabišková, Miloslava (referee)
Permeation enhancers are compounds that promote drug flux into systemic circulation or adjacent tissues. This doctoral thesis follows our previous results and aims at studying two different groups of potential permeation enhancers: dicarboxylic acid derivatives and analogues of Transkarbam 12. The main purpose of my work was to study the structure- activity relationships in these permeation enhancers and to contribute to the elucidatation of their mechanism of action. The first part of my work was focused on derivatives of dicarboxylic acids. Series of enhancers based on maleic, fumaric, succinic, tartaric and meso-tartaric acids were prepared. The enhancing activity of these compounds was investigated in vitro in Franz diffusion cells using theophylline as a model drug and porcine skin. The single-chain amphiphiles were markedly more effective than the double-chain ones. The most active enhancer, monododecyl maleate, that is a cis- derivative, was a more potent enhancer than its respective trans- isomer. Furthermore, the activity of similar succinates, i.e. compounds having a single bond, strongly depended on the donor vehicle. No difference between diastereoisomeric tartaric and meso-tartaric acid derivatives was found. The second part of my work dealt with Transkarbam 12, an ammonium carbamate...
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Study of chiral aspects of drug metabolism using instrumental analytic methods
Holmanová, Veronika ; Nobilis, Milan (advisor) ; Kovaříková, Petra (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Drug Control Candidate: Bc. Veronika Holmanová Supervisor: Doc. PharmDr. Milan Nobilis, CSc. Title of diploma thesis: Study of chiral aspects of drug metabolism using instrumental analytic methods For the evaluation of stereospecificity of rat and human cytosolic carbonyl reductases and activity of microsomal oxidases involved in nabumetone biotransformation, a new chiral high-performance liquid chromatographic method was developed. The prepared LLE-HPLC-PDA method enabled extraction, separation and ultraviolet detection of prochiral nabumetone and its five phase I metabolites including enantiomers of two chiral biotransformation products of carbonyl reduction. Methyl ester of naproxen served as an internal standard. Diethyl ether was used for liquid-liquid extraction (LLE) of biomatrices. Chiralcel OD-R 250 mm×4.6 mm column with a mobile phase methanol-1M NaClO4/HClO4 aqueous solution pH=3 (75:25, v/v) were employed in isocratic sufficient separation of nine analytes. The whole analysis lasted 60 minutes at the flow rate of 0.5 ml/min. The column effluent was monitored using a photodiode-array detector (scan or single wavelength at λ=265 nm). The results of in vitro nabumetone...
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Phase II biotransformation of NSAID flobufen
Babú, Yogeeta ; Wsól, Vladimír (advisor) ; Nobilis, Milan (referee) ; Kuchař, Miroslav (referee)
Xenobiotic chemicals are chemicals foreign to life that are usually derived synthetically or from an abiotic process. The synthetic xenobiotic chemicals are often of enormous value to human society and are usually the majority of the chemicals in such important groups of substances as petrochemicals, pesticides, plastics and pharmaceuticals, where the term drug is usually applied when referring to xenobiotics. Biotransformation is a major mechanism for drug elimination, as they undergo biotransformation after they enter the body. Biotransformation, which almost always produces metabolites that are more polar than the parent compound, usually terminates the pharmacologic action of the parent drug and, via excretion, increases removal of the drug from the body. However, other consequences are possible, including similar or different pharmacologic activity, or toxicological activity. The routes by which drugs may be biotransformed are many and varied and include oxidation, reduction, hydrolysis and conjugation reactions, among others. It is important that these pathways are understood, as the route of metabolism of a drug can determine its ultimate pharmacological or toxicological activity. Drug biotransformation is divided into two phases: Phase I, or functionalisation reactions and Phase II, or conjugative...
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Analytical evaluation of biologically active compounds using liquid chromatography.
Zerzaňová, Anna ; Klimeš, Jiří (advisor) ; Blešová, Marie (referee) ; Nobilis, Milan (referee)
Disertační práce Summary 133 This dissertation thesis is focused on the analytical evaluation of biologically active compounds with the aid of High Performance Liquid Chromatography, especially with selective and sensitive detection performed by mass and coulometric detector. In the theoretical part of this dissertation thesis, there is attention paid to the importance and status of mass spectrometry as a tool of the modern analytical method of the detection. In this dissertation thesis, there is also a view of electrochemical methods and applications, focusing on coulometric measurements in flow systems. The results of the experimental work have been compiled and presented in three articles published in scientific impact journals. The list of reached results is following: The first article deals with a comparison of four chromatographic columns for their use in bioanalytical studies. Numerous HPLC columns with different bonded stationary phases are nowadays available, and producers continue to expand the range of columns they offer. Four real mixtures of biologically active compounds were used for the testing. Every mixture contained a parent active compound, its real metabolites and proper internal standard. Measurements were performed on two monolithic and two particle-packed columns with quite new...
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