|
|
Retention Behaviour of Catecholamines and Their Precursors under HILIC Conditions
Tibenský, Andrej ; Kastner, Petr (advisor) ; Štěrbová, Petra (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Andrej Tibenský Supervisor: PharmDr. Petr Kastner, Ph.D. Title of thesis: Retention behaviour of catecholamines and their precursors under HILIC conditions The aim of this diploma thesis was to study retention behaviour of catecholamines and their precursors under Hydrophilic Interaction Liquid Chromatography by using spectrophotometric and fluorometric detection. 5 analytes were examined - adrenaline, noradrenaline, dopamine, L-DOPA, and tyrosine. Retention behaviour studying began by using LUNA 3 µm (PFP)2 column which possesses both RPLC and HILIC characteristics with 2 different mobile phases. The first one consisted of 25 mM acetic acid in mixture of acetonitrile and water and the second mobile phase was 25 mM acetate buffer (pH 4,50) in mixture of acetonitrile and water. Subsequently, the effect of stationary phase was studied on neutral column XBridge BEH Amide and columns Avantor ACE HILIC-A and Sequant ZIC-HILIC with ionic interactions. Mobile phases consisted of high proportion of acetonitrile (70-90 %) and their composition was the following - 25 mM acetic acid in mixture of acetonitrile and water. Then, the effect of acetic acid concentration as a mobile...
|
|
|
Evaluation of phenolic substances content in plant material
Hollá, Marcela ; Sklenářová, Hana (advisor) ; Hroboňová, Katarína (referee) ; Štěrbová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Mgr. Marcela Hollá Supervisor: assoc. prof. PharmDr. Hana Sklenářová, Ph.D. Consultant: prof. RNDr. Dalibor Šatínský, Ph.D. Title of Doctoral Thesis: Evaluation of phenolic substances content in plant material Scientific community has always been interested in the research of natural substances. The main reasons are a huge diversity of substances themselves and their significant impact on human health. The development of new analytical and extraction methods, including new approaches for sample preparation, enable obtaining more detailed knowledge about the structure and biological properties of plant substances. A significant group consists of substances with antioxidant effects, such as phenolic compounds, which are an important part of human food. The presented dissertation thesis deals with determination of selected groups of natural substances from the point of view of specific requirements for chromatographic separation, choice of detection technique with regard to the selectivity and sensitivity of the determination, as well as the possibility of applying modern and green extraction approaches. The first part of the presented work is devoted to the issue of determination of selected plant...
|
|
|
Evaluation of Metabolism and Excretion of Endogenous Substances and Xenobiotics
Uher, Martin ; Hroch, Miloš (advisor) ; Peš, Ondřej (referee) ; Štěrbová, Petra (referee)
Despite the significant progress in analytical techniques, the development and validation of methods for determining endogenous compounds is still a challenging task due to the natural presence of the analyte in the investigated biological matrix. In contrast to xenobiotics, which do not normally occur in biological material, endogenous substances represent a fundamental problem leading to the impossibility of obtaining an analyte-free sample, the so-called blank, which is used in the development and validation of a new method for the preparation of reference samples. Several generally accepted procedures to solve this problem are described, such as the use of surrogate matrices, analyte-purified matrices, or surrogate analytes; however, the used procedures do not always meet the requirements for developing a reliable analytical method according to the given guidelines and regulations. This study aimed to propose an alternative approach in the preparation of validation reference samples while preserving the original biological matrix and solving the problem with the natural presence of analyzed compounds in these samples and, subsequently, apply the validated method as part of metabolomic studies focused on the research of selected liver diseases. The presented procedure is based on the standard...
|
|
|
Retention Behaviour of Catecholamines and Their Precursors under HILIC Conditions
Tibenský, Andrej ; Kastner, Petr (advisor) ; Štěrbová, Petra (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Andrej Tibenský Supervisor: PharmDr. Petr Kastner, Ph.D. Title of thesis: Retention behaviour of catecholamines and their precursors under HILIC conditions The aim of this diploma thesis was to study retention behaviour of catecholamines and their precursors under Hydrophilic Interaction Liquid Chromatography by using spectrophotometric and fluorometric detection. 5 analytes were examined - adrenaline, noradrenaline, dopamine, L-DOPA, and tyrosine. Retention behaviour studying began by using LUNA 3 µm (PFP)2 column which possesses both RPLC and HILIC characteristics with 2 different mobile phases. The first one consisted of 25 mM acetic acid in mixture of acetonitrile and water and the second mobile phase was 25 mM acetate buffer (pH 4,50) in mixture of acetonitrile and water. Subsequently, the effect of stationary phase was studied on neutral column XBridge BEH Amide and columns Avantor ACE HILIC-A and Sequant ZIC-HILIC with ionic interactions. Mobile phases consisted of high proportion of acetonitrile (70-90 %) and their composition was the following - 25 mM acetic acid in mixture of acetonitrile and water. Then, the effect of acetic acid concentration as a mobile...
|
|
|
Development of LC-MS method for determination of selected endocrine disruptors
Chvalkovská, Eliška ; Kučera, Radim (advisor) ; Štěrbová, Petra (referee)
Charles University Phaculty od Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Eliška Chvalkovská Supervisor: doc. PharmDr. Radim Kučera, Ph.D. Consultant: Mgr. Martin Novák Title of thesis: Development of LC-MS method for determination of selected endocrine disruptors The thesis is focused on the development and optimization of LC-MS method for the determination of twelve endocrine disruptors in amniotic fluid of pregnant women in the third trimestr of pregnancy. There is a suspision that premature births are connected with an increased incidence of endocrine disruptors in amniotic fluid. The analytes were extracted by liquid-liqud extraction with 4-methylpentan-2- on. The analytical method is based on using reverse phase high-performance liquid chromatography with Hypersil C4 GOLD column (2.1 × 100 mm, particles 1.9 µm). For analysis the gradient elution with the mobile phase A (0.5% (v/v) formic acid aqueous solution) and B (0.5% (v/v) formic acid solution in acetonitrile) at a flow rate of 0.5 ml/min, injection 5 µl and column oven temperature 35 řC was used. The high- resolution mass spectrometer Orbitrap Q Exative Plus with atmospheric pressure chemical ionization in positive mode was used to identify and determine the response of...
|
|
|
Assessment of physico-chemical and pharmacokinetic properties of potential antitubercular agents
Nevosadová, Lenka ; Váňová, Nela (advisor) ; Štěrbová, Petra (referee)
This master's thesis focuses on determining the physio−chemical and stability properties of select groups of potential antituberculosis agents such as T, K, LV and G substances. The goal of this work was to expand the portfolio of information necessary as this for subsequent preclinical testing of new potential drugs. The theoretical work introduces the serious global infectious disease, tuberculosis, and the emerging resistance of Mycobacterium tuberculosis strains to current drugs. Furthermore, the developmental directions of new potential antituberculosis drugs and a description of the used analytical methods − spectrophotometry and HPLC analysis − are presented here. The experimental work is dedicated to the description of individual techniques which were used to determine the properties of the selected substances, such as its solubility in 5 % DMSO, stability in plasma, microsomal stability, stability in Šul media, and experimental determination of logP and logD. It is very clear from the experimental results how individual structural changes in the molecules affected some pharmacokinetic or physio−chemical properties of the given substance. For example reducing plasma stability by incorporating sulphur into the carbon liking chain or decrease of microsomal stability by using lacton form. The...
|
|
|
Development of LC-MS method for determination of selected endocrine disruptors
Chvalkovská, Eliška ; Kučera, Radim (advisor) ; Štěrbová, Petra (referee)
Charles University Phaculty od Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Eliška Chvalkovská Supervisor: doc. PharmDr. Radim Kučera, Ph.D. Consultant: Mgr. Martin Novák Title of thesis: Development of LC-MS method for determination of selected endocrine disruptors The thesis is focused on the development and optimization of LC-MS method for the determination of twelve endocrine disruptors in amniotic fluid of pregnant women in the third trimestr of pregnancy. There is a suspision that premature births are connected with an increased incidence of endocrine disruptors in amniotic fluid. The analytes were extracted by liquid-liqud extraction with 4-methylpentan-2- on. The analytical method is based on using reverse phase high-performance liquid chromatography with Hypersil C4 GOLD column (2.1 × 100 mm, particles 1.9 µm). For analysis the gradient elution with the mobile phase A (0.5% (v/v) formic acid aqueous solution) and B (0.5% (v/v) formic acid solution in acetonitrile) at a flow rate of 0.5 ml/min, injection 5 µl and column oven temperature 35 řC was used. The high- resolution mass spectrometer Orbitrap Q Exative Plus with atmospheric pressure chemical ionization in positive mode was used to identify and determine the response of...
|
|
|
Analytical and bioanalytical assessment of novel anticancer drugs
Šesták, Vít ; Štěrbová, Petra (advisor) ; Bednář, Petr (referee) ; Šatínský, Dalibor (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Mgr. Vít Šesták Supervisor - specialist: PharmDr. Ján Stariat, Ph.D. Supervisor: doc. PharmDr. Petra Kovaříková, Ph.D. Title: Analytical and bioanalytical assessment of novel anticancer drugs Pharmaceutical analysis plays an indispensable role in the development of novel safer, cheaper and more effective drugs and chaperones them from their first synthesis throughout their existence. To date, the method most commonly used in pharmaceutical analysis is liquid chromatography (LC) with various detection modalities. Separation via LC enables analysis of very complex mixtures such as biological samples or samples from stability studies. The soaring interest in LC hyphenated with mass spectrometry (MS) in pharmaceutical analysis is partly due to its increasing affordability and mainly due to its ability to separate the molecules of the analyte according to their mass-to-charge ratio (m/z). The additional dimension of separation grants it a superior selectivity. In addition, MS provides priceless information on the structure of the analyte - be it the m/z or fragmentation spectra. In its theoretical part, this dissertation deals with basic description of liquid...
|
|
|
Application of modern separation techniques in the analysis of biological material
Červinková, Barbora ; Solich, Petr (advisor) ; Mikuš, Peter (referee) ; Štěrbová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Department of Analytical Chemistry Candidate Mgr. Barbora Červinková Supervisor prof. RNDr. Petr Solich, CSc. Title of Doctoral Thesis Application of modern separation techniques in the analysis of biological material The presented dissertation is focused on development, optimization and validation of new extraction procedures and chromatographic methods for determination of vitamins A and E, inflammation biomarkers, DNA and RNA oxidative stress products in biological matrices. In the theoretical part of this work selected analytes and possibility of their determination in biological materials are described. Moreover, modern trends in liquid chromatography and bioanalytical validation guidelines are included. In this part, special attention is focused on sample handling, transport and pre- treatment. The second part is focused on published methods and divided into two sections. The first section comments published developed analytical methods. As first method, determination of lipophilic vitamins in human serum by miniaturized liquid-liquid extraction with subsequent separation on fluorinated stationary phase using UHPLC system with fluorescent detection in 4 min is discussed. Thereafter, determination of creatinine, DNA and...
|
|
|
LC-HRMS analysis of selected antihypertensive drugs in biological material for compliance assessment
Tláskalová, Anna ; Kučera, Radim (advisor) ; Štěrbová, Petra (referee)
5 ABSTRACT Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Anna Tláskalová Supervisor - specialist: Mgr. Martin Mžik Supervisor: doc. PharmDr. Radim Kučera, Ph.D. Title: LC-HRMS analysis of selected antihypertensive drugs in biological material for compliance assessment About 40 % of Czech population between the ages of 25 and 64 suffer from arterial hypertension. Although an array of effective antihypertensives is available nowadays, optimal blood pressure during treatment is reached by mere 30 % of the patients. This is mainly due to the patients' poor adherence to the treatment, who use their medicaments incorrectly or not at all. The adherence of a patient to the treatment, as well as pharmacokinetics, represent the most significant source of variability of the answer to the treatment and notably influences its outcome. The monitoring of plasmatic levels of antihypertensives is one of the methods of modern medicine which enables both an effective supervision of the incorrectly compensated patients, and the adjustment of dosage scheme. This diploma thesis focuses on development and optimisation of extraction procedures for selected antihypertensives (amiloride, amlodipine, betaxolol, bisoprolol, carvedilol, celiprolol,...
|
guest ::
RSS feed.