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Stress testing of estradiol and ethynylestradiol
Mašková, Kateřina ; Chocholoušová Havlíková, Lucie (advisor) ; Aufartová, Jana (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Kateřina Mašková Supervisor: PharmDr. Lucie Havlíková, Ph.D. Title of Diploma Thesis: Stress testing of estradiol and ethynylestradiol This diploma thesis is focused on the implementation of stress testing of two estrogenic hormones estradiol and ethynylestradiol. Both substances have been exposed to oxidation and acid and alkaline pH at increased temperature of 70řC for a predefined time period. The results of these tests should have shown a decrease or an increase of the peak area of estradiol and 17α- ethynylestradiol and a potential formation of degradation products. Peak areas and retention times of degradation products were observed by HPLC. The aim of this thesis was to determine the properties of these hormones under various stress conditions like extreme conditions of production, storage, transport and/or under various external influences. Characterization of degradation products and verification of the suitability of methods used for the analysis of degradation products were also aims of this paper. The method was partially validated. In the experimental part there has been found out that estradiol and ethynylestradiol were stable in water as well as in acetonitrile solution...
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Development and validation of HPLC method for the determination of nicotine in spray and in e-cigarette cartridges
Maťátková, Marcela ; Chocholoušová Havlíková, Lucie (advisor) ; Matysová, Ludmila (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Marcela Maťátková Supervisor: PharmDr. Lucie Havlíková, Ph.D. Title of Diploma Thesis: Development and validation of HPLC method for the determination of nicotine in spray and in e-cigarette cartridges The aim of this diploma thesis was the development and validation of HPLC method for the determination of nicotine in mouth spray and in e-cigarette cartridges. The development was based on available methods that deal with HPLC analysis of nicotine and its related compound cotinine. The optimum conditions were found using XTerra® MS C18 column (100 x 4.6 mm, 3.5 µm) with mobile phase acetonitrile : 10mM ammonium acetate pH 9 (20 : 80, v/v). The flow-rate was 1 ml/min and the wavelenght of the detector was set up at 260 nm. Trimethoprim was used as an internal standard. Under these conditions nicotine, cotinine and trimethoprim were separated within 5 minutes. It was impossible to determine cotinine in the analysis of mouth spray and chosen electronic cigarette cartridges due to coelution of used excipients. Therefore the developed HPLC method was validated and system suitability parameters were evaluated only for nicotine. The results of validation demonstrated, that the method provides...
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Determination of estrogen derivatives by sequential injection chromatography
Kosařová, Lucie ; Chocholouš, Petr (advisor) ; Chocholoušová Havlíková, Lucie (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical chemistry Candidate: Mgr. Lucie Kosařová Consultant: PharmDr. Petr Chocholouš, Ph.D. Title of Thesis: Determination of estrogen derivatives by sequential injection chromatography This work presents the first utilization of sequential injection chromatography for determination of four estrogen derivatives with similar structure and an internal standard (ethylparaben) with the use of monolithic column Merck® Chromolith® Performance RP-18e 100 mm × 3 mm and pre-column Merck® Chromolith® RP-18e 5 mm × 3 mm of total length 105 mm. A commercially available SIC system - SIChromTM (FIAlab® Instruments Inc., USA), mobile phase composed of acetonitrile:water 40:60 (v/v) and CCD UV-VIS detector were used. Spectrophotometric detection was set up at wavelength of 225 nm. The injected volume of sample solutions was 10 µl and 3 ml of mobile phase was pumped isocratic at flow rate 8 μl.s-1 . High separation efficiency, good peak symmetry and resolution were obtained at these conditions, showing another possibility of use sequential injection chromatography in analytical chemistry. Keywords: sequention injection chromatography, monolithic columns, estrogens
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The metod development for determination of diazodinitrofenol explosive
Ihnát, Lukáš ; Šatínský, Dalibor (advisor) ; Chocholoušová Havlíková, Lucie (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Consultant: Doc. RNDr. Dalibor Šatínský, PhD. Diploma Thesis Title: The method development for determination of diazodinitrofenol explosive A new HPLC method for determination of diazodinitrophenol alongside with sodium picramate was developed and optimized. Column Ascentis® Express C18 10cm x 3mm; 2.7µm particles was select as most suitable one. Detection of compounds was performed at 220 nm using UV detector. Mobile phase consist of mixture 0.085% H3PO4 and acetonitrile in ratio 70/30. Flow rate was determined at 0.8 ml/min. Column oven temperature was set to 50řC. Retention times under these condition was tDDNP=1.324 min a tPikNa=4.012 min. Keywords: determination, diaziodinitrophenol, sodium picraminate, HPLC, chromatography, dinol, DDNP
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Study of influence of mobile phase composition on selectivity and retention of the analytes on HILIC stationary phases
Štětková, Kateřina ; 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....
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Column switching chromatography for mycotoxines determination in Czech beer samples
Lhotská, Ivona ; Ramos, María Carolina Fernández (advisor) ; Chocholoušová Havlíková, Lucie (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Ivona Lhotská Supervisor, consultant: María Carolina Fernández Ramos, Ph.D, Doc. RNDr. Dalibor Šatínský, Ph.D. Title of Diploma Thesis: Column switching chromatography for mycotoxines determination in Czech beer samples A new fast and sensitive method of high performance liquid chromatography for simultaneous determination of mycotoxins ochratoxin A and citrinin using column- switching system for on-line sample pretreatment was developed. 100 µl of beer was injected directly into the chromatographic system. Isolation of analytes was performed on guard column Ascentis Express RP-C18 (5 x 4.6 mm, 2.7 µm) washing out with methanol - water solution of acetic acid 0.5% (30:70, v/v), at a flow rate 2 ml/min; time of valve switch was set on 2 minutes. The separation was performed on Ascentis Express Phenyl-Hexyl column (100 x 4.6 mm, 2.7 µm) with mobile phase of composition acetonitril - water solution of acetic acid 0.5% at a flow rate 1 ml/min. A gradient was increasing up to 75:25 linearly in time 3 - 5.5 min. The temperature 50řC was set up for column separation. Wavelengths of fluorimetric detection were set at Ex 335 nm, Em 497 nm. Analysis of one sample including on-line pretreatment was...
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Development of HPLC method for the determination of 6-gingerol, capsaicin, 8-gingerol, 6-shogaol and 10 gingerol in Zingiber officinale samples
Urbanová, Martina ; Chocholoušová Havlíková, Lucie (advisor) ; Matysová, Ludmila (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Martina Urbanová Supervisor: PharmDr. Lucie Havlíková, Ph.D. Title of Diploma Thesis: Development of an HPLC method for the determination of 6-gingerol, capsaicin, 8-gingerol, 6-shogaol and 10-gingerol in Zingiber officinale samples The diploma thesis was focused on the development of an HPLC method for the determination of 6-gingerol, capsaicin, 8-gingerol, 6-shogaol and 10-gingerol in Zingiber officinale samples. At first, freshly prepared rhizome samples of ginger were selected. Afterwards, levels of analytes in model dried ginger powder samples were evaluated. 6-gingerol had always showed highest response in both fresh rhizome samples of ginger and dried ginger powder samples. Capsaicin has not been found in any sample. 6-shogaol has only been found in dried ginger powder samples. Extraction of other substances depended on the methodology of preparation of particular samples. During the optimization of this method, various mobile and stationary phases were examined. The suitable mobile phase was composed of acetonitrile and water in 50/50 (v/v) ratio. Ascentis® Express Phenyl-Hexyl analytical column (100 x 4.6 mm; 2.7 µm) was chosen as a stationary phase for analysis, which was also...
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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)...
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