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Supercritical fluids for extraction of biologically active compounds from Eucalyptus leaves
Herbsová, Diana ; Pilařová, Veronika (advisor) ; Sklenářová, Hana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Bc. Diana Herbsová Supervisor: PharmDr. Veronika Pilařová, PhD. Title of the diploma thesis: Supercritical fluids for extraction of biologically active compounds from Eucalyptus leaves Eucalyptus is nowadays used for its anti-inflammatory, antibacterial, and antioxidant effects in the pharmaceutical and cosmetic industries. Eucalyptus contains various compounds including flavonoids, volatile compounds, terpenoid acids, and phenolic acids. The aim of this work was to develop a two-step selective extraction method for the extraction of compounds of different physicochemical properties from Corymbia citriodora leaves using extraction solvent containing CO2. Supercritical CO2 is a non-polar solvent with polarity and physicochemical properties, that can be changed by mixing with a suitable polar solvent. In this way, a wide range of compounds with different polarities can be extracted. In this study, the key parameters, including temperature in the range of 40-80 řC, pressure in the range of 100-300 bar were optimized using Box-Behnken design with heptane and ethanol/H2O as a cosolvent. After optimalization of the key parametres, the extraction kinetics were tested at flow rates of 2 mL/min and 4...
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Optimalization of sample preparation step for UHPLC-MS/MS analysis of atorvastatin, rosuvastatin and their metabolites
Pilařová, Veronika ; Nováková, Lucie (advisor) ; Chocholoušová Havlíková, Lucie (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of analytical chemistry Candidate: Veronika Pilařová Supervisor: Doc. PharmDr. Lucie Nováková Ph.D. Title of GraduationThesis: Optimalization of sample preparation step for UHPLC-MS/MS analysis of atorvastatin, rosuvastatin and their metabolites The purpose of this graduation thesis was the optimalization of UHPLC-MS/MS method for the determination of concentrations of atorvastatin, rosuvastatin and their metabolites in biological material, and then development and optimalization of a MEPS (microextraction by packed sorbent) method for sample preparation of biological material and validation of this method. Acquity BEH C18 column (50 x 2.1 mm, 1.7 µm, Waters) was used for the separation of the analytes. Electrospray ionization was performed in both negative and positive ion mode. Triple quadrupole mass analyser was used for detection. Precursor ions and fragment ions were chosen for each statin. Collision energy and cone voltage were optimized for all analytes individually. Quantification of analytes was performed using the SRM (selected reaction monitoring). Protonated molecule [M+H]+ , which was measured in the positive ion mode, was chosen as a precursor ion for rosuvastatin lactone. Ion [M-H]- , which was measured in...
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Application of supercritical fluid chromatography in analysis of natural compounds
Lacmanová, Tereza ; Nováková, Lucie (advisor) ; Pilařová, Veronika (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Tereza Lacmanová Supervisor: Assoc. Prof. PharmDr. Lucie Nováková, Ph.D. Title of Diploma Thesis: Application of supercritical fluid chromatography in analysis of natural compounds The goal of this diploma thesis is to verify the suitability of UHPSFC method with PDA and MS detection for analysis of natural products. For the analyzes, two representatives of natural compounds - the alkaloids of the family Amaryllidaceae with effect in the treatment of Alzheimer's disease and phenolic compounds with antioxidant activity - flavonoid rutin, quercetin and their metabolites were chosen. Separations were carried out on the UHPSFC system Acquity UPC2 with PDA and MS detector. The basic screening was performed on 10 stationary phases: BEH 2-EP, HSS SB C18, BEH, Torus DIOL, Torus 2-PIC, Torus DEA, CSH PFP, Torus 1-AA, Cortecs HILIC and BEH Amide. Four mobile phases were tested: 1. CO2 + MeOH, 2. CO2 + MeOH + 0.1 % NH4OH, 3. CO2 + MeOH + 10 mM ammonium formate, and 4. CO2 + MeOH + 10 mM ammonium formate + 2 % H2O. Separation conditions were as follows: flow rate 1.5 ml/min, temperature 40 řC, pressure 140 bar, gradient elution from 2 % to 40 % within 4 minutes, with two isocratic steps at the beginning and...
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Family and its Importance in a Child's Life
Pilařová, Veronika ; Sotáková, Hana (advisor) ; Presslerová, Pavla (referee)
This thesis deals with family education and the importance of family for the child of preschool age. The theoretical part provides expert knowledge of the child of preschool age, family upbringing. Furthermore it describes concepts of family, its functions and finally family in child's drawing. The empirical part is focused on the research study of families and its significance for the child. It emphasizes the time parents spent with children, the family environment and the overall family situation. The research is conducted using interviews with children, mothers and teachers. To underline the entire research I also analyzed children's drawings.
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Development and optimization of sample preparation step for fast chromatographic analysis
Pilařová, Veronika ; Nováková, Lucie (advisor) ; Bednář, Petr (referee) ; Šatínský, Dalibor (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of analytical chemistry Candidate Mgr. Veronika Pilařová Supervisor Assoc. Prof. Lucie Nováková, Ph.D. Title of Doctoral Thesis Development and optimization of sample preparation step for fast chromatographic analysis. The aim of the dissertation thesis is the development of modern extraction methods for the sample purification and for the analytes isolation and preconcentration from various biological materials, including biological fluids (plasma, serum, vaginal lavages) and plant material. Modern approaches have a lots of advantages such as a lower consumption of sample and organic solvents, extraction speed-up, better sample purification, matrix removal and lower influence of matrix effects. Extracts from modern microextraction methods can be analyzed by separation methods including ultra-high performance liquid chromatography and supercritical flluid chromatography coupled with mass spectrometry. The separation methods enable fast high-throughput analysis with sensitive and selective detection. Individual projects show the possibilty of use of the modern approaches in the sample preparation field, where the microextraction by packed sorbent (MEPS), microextraction by solid phase extraction in pipette tips...
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Development of supercritical fluid extraction for isolation of biologically active substances
Kuda, Lukáš ; Pilařová, Veronika (advisor) ; Sklenářová, Hana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Lukáš Kuda Supervisor: PharmDr. Veronika Pilařová, Ph.D. Title of Diploma Thesis: Development of Supercritical Fluid Extraction for Isolation of Biologically Active Substances The main aim of this study was to optimize the method for extraction of quercetin - flavonoid with antioxidant activity - from dried crushed quince fruit (Cydonia oblonga Mill.) using supercritical fluid extraction (SFE). The supercritical fluid extraction is a method in which supercritical fluid is used to extract active compounds. Neat CO2 is the most common used solvent. Due to its physicochemical properties, it is suitable solvent for the extraction of non-polar compounds. While extraction of polar compounds id required, the organic solvents such as ethanol, methanol or isopropanol are added to the supercritical fluid. Depending on the amount of added organic solvent, SFE, SFE with modifier, CO2 expanded liquid extraction and pressurized liquid extraction are distinguished. Temperature and pressure are other key parameters affecting extraction and need to be optimized as well. The optimization of the quercetin extraction method was carried out in several following steps. First, the key parameters were tested using...
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Optimization of extraction of phenolic substances using carbon dioxide
Karola, Michal ; Sklenářová, Hana (advisor) ; Pilařová, Veronika (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Michal Karola Supervisor: doc. PharmDr. Hana Sklenářová, Ph.D. Advisor: Mgr. Marcela Hollá Title of diploma thesis: Optimization of extraction of phenolic substances using carbon dioxide This diploma thesis deals with the optimization of extraction of phenolic substances by supercritical fluid extraction, using carbon dioxide, from a sample of homogenized dried apple chips. To quantify and identify the analytes contained in the extract, 14 standards were analysed using a separation method in a UHPLC system with a diode array detector. In the identification of the extracts' components, 13 analytes were identified and after their quantification, 6 analytes were found to have major content. The difference in the sum of the concentrations of the 6 and 13 analytes was small, and therefore, optimization was carried out for these 6 majorly represented analytes, which are chlorogenic acid, epicatechin, catechin, phloridzin, quercitrin, and guaiaverin. The extraction optimization was carried out in 4 successive steps. The first step of the optimization was to determine the influence and significance of CO2 content in the extraction medium, H2O content in the ethanolic cosolvent, pressure and temperature...
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Development of supercritical fluid extraction for isolation of biologically active substances
Kuda, Lukáš ; Pilařová, Veronika (advisor) ; Sklenářová, Hana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Lukáš Kuda Supervisor: PharmDr. Veronika Pilařová, Ph.D. Title of Diploma Thesis: Development of Supercritical Fluid Extraction for Isolation of Biologically Active Substances The main aim of this study was to optimize the method for extraction of quercetin - flavonoid with antioxidant activity - from dried crushed quince fruit (Cydonia oblonga Mill.) using supercritical fluid extraction (SFE). The supercritical fluid extraction is a method in which supercritical fluid is used to extract active compounds. Neat CO2 is the most common used solvent. Due to its physicochemical properties, it is suitable solvent for the extraction of non-polar compounds. While extraction of polar compounds id required, the organic solvents such as ethanol, methanol or isopropanol are added to the supercritical fluid. Depending on the amount of added organic solvent, SFE, SFE with modifier, CO2 expanded liquid extraction and pressurized liquid extraction are distinguished. Temperature and pressure are other key parameters affecting extraction and need to be optimized as well. The optimization of the quercetin extraction method was carried out in several following steps. First, the key parameters were tested using...
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Application of supercritical fluid chromatography in analysis of natural compounds
Lacmanová, Tereza ; Nováková, Lucie (advisor) ; Pilařová, Veronika (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Tereza Lacmanová Supervisor: Assoc. Prof. PharmDr. Lucie Nováková, Ph.D. Title of Diploma Thesis: Application of supercritical fluid chromatography in analysis of natural compounds The goal of this diploma thesis is to verify the suitability of UHPSFC method with PDA and MS detection for analysis of natural products. For the analyzes, two representatives of natural compounds - the alkaloids of the family Amaryllidaceae with effect in the treatment of Alzheimer's disease and phenolic compounds with antioxidant activity - flavonoid rutin, quercetin and their metabolites were chosen. Separations were carried out on the UHPSFC system Acquity UPC2 with PDA and MS detector. The basic screening was performed on 10 stationary phases: BEH 2-EP, HSS SB C18, BEH, Torus DIOL, Torus 2-PIC, Torus DEA, CSH PFP, Torus 1-AA, Cortecs HILIC and BEH Amide. Four mobile phases were tested: 1. CO2 + MeOH, 2. CO2 + MeOH + 0.1 % NH4OH, 3. CO2 + MeOH + 10 mM ammonium formate, and 4. CO2 + MeOH + 10 mM ammonium formate + 2 % H2O. Separation conditions were as follows: flow rate 1.5 ml/min, temperature 40 řC, pressure 140 bar, gradient elution from 2 % to 40 % within 4 minutes, with two isocratic steps at the beginning and...
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