|
|
Use of UHPLC-MS/MS method for the evaluation of the effect of flavouring additives on the content of catechins in tea samples and matrix effects
Pavlík, Jakub ; Nováková, Lucie (advisor) ; Chocholoušová Havlíková, Lucie (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Jakub Pavlík Supervisor: Assoc. Prof. PharmDr. Lucie Nováková, Ph. D. Title of Diploma thesis: Use of UHPLC-MS/MS method for the evaluation of the effect of flavouring additives on the content of catechins in tea samples and matrix effects This diploma thesis is based on the findings published in the Journal of Pharmaceutical and Biomedical Analysis [1], which describes the incidence of matrix effects in several samples of flavored tea infusions. Measured matrix effects were not very high (ranging from -5.3% to + 10.4%), as well as the number of analyzed samples. Therefore, the research in this thesis was focused on the analysis of commercially available teas using a tea bagged (Pickwick) and loose leaf tea (Basilur). Loose leaf tea has been used for the preparation of custom blends with better defined composition. In total, 11 different flavors which are commonly used were tested in this study including: cranberry fruits, mint leaf, rosehip fruit, lemon zest, orange zest, ginger root, rose flower, cinnamon bark, lemon grass, jasmine blossom and vanilla. Analyses were carried out on the ACQUITY Ultra Performance LC coupled to triple quadrupole mass spectrometer Quattro Micro (Waters)...
|
|
|
Study of influence of mobile phase composition on selectivity and retention of the analytes on HILIC stationary phases
Štětková, Kateřina ; Kočová Vlčková, Hana (advisor) ; Chocholoušová Havlíková, Lucie (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Kateřina Štětková Supervisor: RNDr. Hana Vlčková, Ph.D. Title of Diploma thesis: Study of influence of mobile phase composition on selectivity and retention of the analytes on HILIC stationary phases This graduation thesis deals with an influence of concentration of ACN, pH and buffer concentration in mobile phase on retention of selected analytes and on selectivity of Atlantis HILIC Silica column (3 μm, 2,1 mm x 100 mm) and Luna NH2 column (3 μm, 2,0 mm x 100 mm). A set of 35 analytes including neutral, basic and acidic compounds were chosen for this study. Detection was performed by PDA detector at the wave-length of 245 nm. Measurements were carried out using isocratic flow 0.4 ml.min-1 of mobile phase ACN/water (buffer). The column temperature was set up to 30 řC, auto sampler temperature to 4 řC and injection volume to 2 µl. For easier evaluation of results, measured data are presented in charts and tables. These were used to evaluation of columns in terms of selectivity and retention of the individual groups of analytes. The typical HILIC behavior, an increasing retention of analytes with increasing ACN concentration in mobile phase, was observed for Atlantis HILIC Silica column....
|
|
|
Comparison of selectivity and retention of the analyties on two HILIC stationary phases
Hodovská, Nikola ; Vlčková, Hana (advisor) ; Chocholoušová Havlíková, Lucie (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Nikola Klvanová Supervisor: RNDr. Hana Vlčková, Ph.D. Title of Diploma thesis: Comparison of selectivity and retention of the analytes on two HILIC stationary phases This diploma thesis deals with an influence of ACN concentration, pH and buffer concentration in mobile phase on the retention of tested analytes and selectivity of two analytical columns Luna HILIC (diol) column (3 μm, 3 mm x 100 mm) and Ascentis ES Cyano column (3 μm, 2.1 mm x 100 mm). A set of 28 analytes including neutral, basic and acidic compounds was chosen for this study. Detection was performed by PDA detector at the wave-length of 245 nm. Measurement was performed isocratically at the mobile phase flow rate of 0.7 ml/min and 0.3 ml/min. Mobile phase was consisted of a mixture of acetonitrile and water component (buffer or acetic acid). The column temperature was set up to 30 řC, autosampler temperature to 4 řC. Injection volume was 5 μl or 3 μl. For easier evaluation of results, measured data are presented in the charts and tables. The influence of the ACN content in mobile phase was evaluated based on the plots of the retention factor that showed increasing retention with increasing ACN content (typical HILIC...
|
|
|
HPLC method development for artificial colorants determination in green beer samples
Stachová, Ivana ; Šatínský, Dalibor (advisor) ; Chocholoušová Havlíková, Lucie (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Bc. Ivana Stachová Supervisor: Doc. RNDr. Dalibor Šatínský, Ph. D. Title of diploma Thesis: HPLC method development for artificial colorants determination in green beer samples HPLC method was used and validated for the simultaneous determination of synthetic water- soluble dyes: E 102 - Tartrazine, E 104 - Quinoline Yellow, E 110 - Sunset Yellow, E 131 - Patent blue, E 132 - Indigo carmine, E 142 - Green S, E 133 - Brilliant Blue FCF and E 143 - Fast Green FCF. The method was applied for direct determination of these dyes in samples of green beers Jarní pivo 11ř (Primátor, Náchod), Krasličák 14ř (Ježek, Jihlava), Zelený král Vratislav 12ř (Konrád, Vratislavice), Velikonoční speciál 14ř (Starobrno, Brno), Velikonoční ležák 12ř (Radniční pivovar, Jihlava) Rohozec 11ř (Rohozec, Malý Rohozec), Zelená nefiltrovaná 12ř (Žlebské Chvalovice), Velikonoční zelený ležák 12ř (Purkmistr, Plzeň), Velikonoční kopřivová 12ř (Modrá Hvězda, Dobřany), Valášek 12ř (Valášek, Vsetín), Podkováň 12ř (Podkováň, Dolní Cetno). Analytical Chromolith Performance CN 100 x 4.6 mm column and guard column Chromolith CN 5 x 4.6 mm Merck were used and mobile phase contained 40% (v/v) methanol / 2% (v/v) acetic acid...
|
|
| |
|
|
Development of HPLC method for the determination of amygdalin and serotonin in dietary supplement
Parmová, Martina ; Chocholoušová Havlíková, Lucie (advisor) ; Aufartová, Jana (referee)
The analytical method for the determination of amygdalin and serotonin supplement B17 APRICARC using high-performance liquid chromatography was developed and validated. The 96 % ethanol was used for the extraction to obtain analytes. As a suitable chromatographic column was chosen the column Ascentis Express® OH5 (3 x 100 mm, 2,7 µm). The composition of the mobile phase for the analysis was 10 mM acetate buffer pH 3.8 : acetonitrile 10:90 (v:v). The flow rate was set on 0.8 mL / min, for the detection of amygdalin was used an UV detector (wavelength 215 nm) and for the detection of serotonin was used the fluorescence detector (Ex 280 nm , Em 340 nm ). A suitability test of chromatographic system was performed and these parameters were pursued: column efficiency, resolution peak symmetry factor and repeatability of analysis. Within the actual validation these parameters were pursued: accuracy, linearity, precision, and limit of detection and quantification.
|
|
| |
|
|
Development of MEPS method for UHPLC-MS/MS determination of entecavir in renal ultrafiltrate
Janák, Jaroslav ; Vlčková, Hana (advisor) ; Chocholoušová Havlíková, Lucie (referee)
1 Abstract Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of analytical chemistry Candidate: Jaroslav Janák Supervisor: RNDr. Hana Vlčková, Ph.D. Title of Thesis: Development of MEPS-UHPLC-MS/MS methods for the determination of entecavir in kidney ultrafiltrate. The thesis deals with the development and validation of sample preparation method for determination of entecavir in kidney ultrafiltrate, using techniques MEPS (microextraction by packed sorbent). The previously developed UHPLC-MS/MS method for the determination of entecavir in rat urine has been used for the analysis. Hydrophilic interaction chromatography by column Acquity BEH Amide and isocratic elution were employed. The composition of the mobile phase was acetonitrile and 5 mM ammonium acetate pH 4.0 in the ratio 75:25 (v:v). Entecavir C2 13 N15 was used as the internal standard. Ionization of the analyte was carried out by electrospray in the positive ion mode and triple quadrupole was employed as the detector. Quantification of the analyte was realized by two SRM transitions of entecavir and internal standard method. Based on the MEPS optimization method, porous graphitic carbon suitable for the analysis of polar compounds was selected as the most suitable sorbent. The mixture of acetonitrile and water in a...
|
|
|
Forced degradation studies of dimethindene maleate using HPLC
Pannyová, Anna ; Chocholoušová Havlíková, Lucie (advisor) ; Kujovská Krčmová, Lenka (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Student: Anna Pannyová Supervisor: PharmDr. Lucie Havlíková, Ph.D. Title of diploma thesis: Forced degradation studies of dimethindene maleate using HPLC The aims of this thesis were to perform forced degradation of dimethindene maleate and to optimize the chromatographic conditions for the determination of dimethindene maleate and its related compounds. The stress testing was conducted with drug product/drug in order to exam its stability. Decomposition of the product can lead to loss of the content of the active substance, loss of their pharmacological activity or forming of degradation products. Dimethindene maleate is an antihistamine drug. He affects H1 histamine receptors. Nowadays, high performance liquid chromatography (HPLC) is one of the most used separation techniques for the determination of the drug stability. The stability of dimethindene maleate was investigated using stress testing (forced degradation studies). Dimethindene was stable in aqueous and acid solution as well as under heating (70řC). Significant degradation was observed when the drug was subjected to basic and oxidation stress conditions; this led to the formation of two degradation products DP1 and DP2 (described using...
|
|
|
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...
|
guest ::
