|
|
Fluorescence detection of metsulfuron methyl in the SIA system
Labaštová, Petra ; Sklenářová, Hana (advisor) ; Chocholouš, Petr (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of analytical chemistry Candidate: Petra Bolinová Supervisor: Doc. PharmDr. Hana Sklenářová, Ph.D. Title of Diploma Thesis: Fluorescence detection of metsulfuron methyl in the SIA system This diploma work deals with fluorescence detection of quinine and metsulfuron methyl (MSM) in aqueous media and organic solvents using sequential injection analysis. This method was chosen to detect herbicide for easy sample application, its low consumption fast results evaluation and higher sensitivity of fluorescence compared to spectrophotometric detection. Chininium sulphate solution was used only as a model substance. The main subject of monitoring was the fluorescence detection of MSM in various organic solvents. Sample of MSM was dissolved in different solvents or mixture of solvents (water, acetone, a mixture of water: acetonitrile, chloroform) and in some cases pH was adjusted and UV degradation of the parent compound was carried out, pH adjustment was ensured by the addition of concentrated H2SO4 to pH = 2. Degradation of MSM was tested with UV at 254 nm and 366 nm. The most advantageous of the tested organic solvents in terms of a signal provided was chloroform. Signal intensity of MSM in chloroform solutions compared to the...
|
|
|
HPLC determination of selected incestisides in cosmetic
Kameníčková, Daniela ; Šatínský, Dalibor (advisor) ; Chocholouš, Petr (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Daniela Kameníčková Supervisor: Doc. RNDr. Dalibor Šatínský, Ph.D. Title of Diploma Thesis: HPLC determination of selected incestisides in cosmetic Active ingredients fenoxycarb and permethrin were determined in cosmetic anti- parasitic product Arpalit® Neo shampoo against parasites with bamboo extract. Analysis was performed by HPLC using RP-Amide column 100 x 3 mm with a particle size of 2.7 micron and detection by UV at a wavelength of 225 nm. Separation proceeded by isocratic elution with mobile phase of acetonitrile - water (55:45) at a flow rate 1.0 ml/min. Temperature during measurement was 60 řC. For evaluation method was used an internal standard method, as the internal standard was used dye sudan II. For separation was needed time interval of 6 min. The retention time of fenoxycarb was 1.01, sudan II 2.87 and permethrin 4.42 min. Resolution of chromatographic peaks fenoxycarb and sudan II was 10.612 and sudan II and permethrin 6.524. Keywords: fenoxycarb, permethrin, HPLC.
|
|
|
Separace vybraných anorganických iontů pomocí sekvenční injekční chromatografie
Jarošová, Patrícia ; Horstkotte, Burkhard (advisor) ; Chocholouš, Petr (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Patrícia Jarošová Supervisors: Dr. Burkhard Horstkotte, Ph.D., M.Sc. Doc. PharmDr. Hana Sklenářová, Ph.D. Title of Diploma Thesis: Separation of selected inorganic ions using the sequential injection chromatography The ability of the guard column Dionex Ionpac® CG5A (2 x 50 mm, P/N 046104) to separate some transition metal cations from water samples, using Sequential injection chromatography (SIC) system was demonstrated. The type of separation was based on ion exchange interaction and the column was filled with particles functionalized by a bilayer of anion-exchange and cation-exchange latex. The chelating agent used in eluent was pyridine- 2,6-dicarboxylic acid (PDCA). A post-column reagent with 4-(2-pyridylazo) resorcinol (PAR) was used for spectrophotometric detection. For optimization, two methods were used: Simplex and univariant studies. Ideal conditions of the separation were found. The mobile phase consisted of PDCA, formic acid, sodium sulphate, and sodium hydroxide in the concentrations 4 mmol/l, 40 mmol/l, 4 mmol/l and 2 mmol/l, respectively. The concentrations of the post-column reagent components were 0.3 mmol/l of PAR, 150 mmol/l of the ammonium hydroxide, 60 mmol/l of...
|
|
|
The development of HILIC method for UHPLC-MS/MS determination of pteridins, a comparison of selectivity of various stationary phases.
Jánská, Radka ; Nováková, Lucie (advisor) ; Chocholouš, Petr (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Radka Jánská Supervisor: PharmDr. Lucie Nováková, Ph.D. Title of Doctoral Thesis: The development of HILIC method for UHPLC-MS/MS determination of pteridins, a comparison of selectivity of various stationary phases This graduation thesis was dealing with the development of HILIC method for the identification and quantification of biologically active substances neopterin, biopterin, 7,8- dihydroneopterin and 7,8-dihydrobiopterin by ultra-high performance liquid chromatography coupled to the mass spectrometry detector of triple quadrupole type. Three chromatographic columns (BEH Glycan, BEH Amide and BEH HILIC) were tested. Several mobile phases and their influence on the separation of target analytes were tested. Mobile phase consisted of aqueous component (acetic and formic acid, ammonium formate and acetate and ammonim hydroxide of low concentration) and acetonitrile. On the chromatographic column BEH Glycan following best mobile phases were evaluated: 1mM ammonium acetate pH= 3.8 with acetonitrile in the ratio 30:70 and 1mM ammonium acetate pH= 6.8 with acetonitrile in the ratio 28:72. Two mobile phases composed of 1mM ammonium acetate pH= 4.8 with acetonitrile in the ratio 23:77 and...
|
|
|
Development of on-line SPE HPLC method for determination of ochratoxin A in Tokaj wines
Uhrová, Adéla ; Šatínský, Dalibor (advisor) ; Chocholouš, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Bc. Adéla Uhrová Supervisor, consultant: Doc. RNDr. Dalibor Šatinský, Ph.D. Title of Diploma Thesis: Development of on-line SPE HPLC method for determination of ochratoxin A in Tokaj wines This diploma thesis deals with the optimization and validation of chromatographic method for determination of ochratoxin A in Tokaj wine with subsequent application on real samples. A high- performance liquid chromatography method with fluorescence detection using on-line extraction by column switching has been developed. 50µl of sample was injected directly in the extraction column, where at 1st minute the analyte was extracted on the Ascentis® Express RP-Amide precolumn in the presence of a mobile phase of 40% MeOH in 0.5% aqueous acetic acid. After the extraction, the valve was switched and the extracted substances were separated on a YMC Triart C18 ExRS analytical column. The separation was carried out under gradient elution with an initial acetonitrile ratio of 45% in the mobile phase, which reached a concentration of 80% in the 5th minute. Fluorimeter detection was optimized for excitation and emission wavelengths ʎEx 335 nm and ʎEm 463 nm. In the last part of the work, ochratoxin A was analyzed in real...
|
|
|
On-line solid phase extraction using sequential injection analysis
Hadysová, Zuzana ; Chocholouš, Petr (advisor) ; Sklenářová, Hana (referee)
Department: Department of Analytical chemistry Candidate: Bc. Zuzana Hadysová Supervisor: PharmDr. Petr Chocholouš, Ph.D. Title of the diploma thesis: On-line solid phase extraction using sequential injection analysis This diploma thesis is focused on the comparison of three sorbents (Iontosorb OXIN 50, Iontosorb Oxin 100 and TOYOpearl AF-chelate-650M) with the aim to find the most suitable one for analysis of Zn2+ using on-line solid phase extraction based on sequential injection analysis. Zinc sulphate solutions at concentrations of 25 nmol/l, 50 nmol/l, 100 nmol/l, 200 nmol/l, 500 nmol/l, 1000 nmol/l, 1500 nmol/l and 2000 nmol/l were used in this work. During the analysis was used the buffer at pH 6, the elution solution HCl at pH 1 and the reagent 4-(2-Pyridylazo)resorcinol (PAR). The effort was to extract Zn2+ at the lowest possible concentrations. Tested parameters were calibration range and repeatability. The best sorbent in comparison was Iontosorb OXIN 100.
|
|
| |
|
|
Development UHPLC-MS/MS method and sample preparation procedure for the determination of steroid compounds in rat plasma
Hromádko, Jiří ; Kočová Vlčková, Hana (advisor) ; Chocholouš, Petr (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Jiří Hromádko Supervisor: RNDr. Hana Kočová Vlčková Ph.D. Title of Diploma Thesis: Development UHPLC-MS/MS method and sample preparation procedure for the determination of steroid compounds in rat plasm The diploma thesis deals with the development of the UHPLC-MS/MS method for the analysis of 37 steroids in plasma and optimization of sample preparation using PP. The analytes include structurally very similar substances with different numbers of hydroxyl or ketonic functional groups, isomeric and mutually isobaric compounds. Since these substances cleave water molecules very easily, precursor ions with one m/z for different substances can be found in the MS spectrum. For these reasons, careful and detailed characterization of the precursors, subsequent scanning of the product ions, and selection of additional SRM transitions were essential. Separation of critical compounds with the same m/z for precursor ions was of importance. The optimization started with the screening of 7 columns using gradient elution of the mobile phase ACN/0.1 % FA in the range of 5 - 98% ACN. Based on the results, an optimization of the mobile phase gradient was performed. The Cortecs C18 column was optimal. Most of the...
|
|
|
Automation of liberation tests for releasing biologically active substances from nanofibers
Schneidrová, Marie ; Sklenářová, Hana (advisor) ; Chocholouš, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of analytical chemistry Candidate: Marie Schneidrová Supervisor: doc. PharmDr. Hana Sklenářová, Ph.D. Title of the diploma thesis: Automation of liberation tests for releasing biologically active substance from nanofibers The main goal of this diploma thesis is an automation of TTC liberation from nanofibers, using non-separation flow method sequential injection analysis. UV-VIS spectrophotometer was used for the detection of signal. Measurements were carried out using 1-3 connected Franz cells in parallel, palced in the water bath. Buffer solutions with pH 7.4 and 4.5 were used as liberation media. The liberation of TTC was realized from two different nanofiber carriers - types "A" and "AK", Difference was in their preparation process. Because of this, each of them revealed various characteristics mainly related to the amount of bound TTC and the way of its binding to the nanofiber carrier. Production of these nanofibers was realized by Technical University Liberec using the technology NanoSpiderTM . Measurements were performed under various predetermined conditions, representing the state of the human skin - two different pH (7.4; 4.5) and temperature (32řC; 37řC) values. Four different types of membrane filters were also used,...
|
|
|
Analysis of steroids from the group of angrogens and glucocorticoids using UHPSFC-MS/MS
Gazárková, Taťána ; Nováková, Lucie (advisor) ; Chocholouš, Petr (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Taťána Gazárková Supervisor: prof. PharmDr. Lucie Nováková, Ph.D. Title of Diploma Thesis: Analysis of steroids from the group of androgens and glucocorticoids using UHPSFC-MS/MS The goal of this study was to develop and optimize an analytical method for the separation of 37 steroids mixture by the ultra-high performance supercritical fluid chromatography hyphenated to mass spectrometry (UHPSFC-MS/MS). Analysis was carried out using Waters Acquity UPC2 system coupled to Xevo TQ-XS mass spectrometer. In the first step it was necessary to consistently characterize the precursor ions of each analyte. Then, the Product ion scan was carried out and proper SRM transitions were chosen. Steroids are isomeric and isobaric substances that often provide the same precursor ions ([M+H]+ , [M+H-H2O]+ , eventually [M+H-2H2O]+ ), or similar fragmentation spectra. This is complicated by the fact that most intense ion of the spectrum is not always [M+H]+ , but also [M+H-H2O]+ ion which is simultanously isobaric m/z for a completely differnt compoud. After careful selection of SRM transitions, the conditions of the ion source were optimized for both positive and negative modes. In the next step, the screening of 18...
|
guest ::
