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The Titrimetric determination with thermometric detection.
Nohavová, Ivana ; Opekar, František (advisor) ; Coufal, Pavel (referee)
Thermometric detection is one of the less usual methods for the objective titration end- point detection. The temperature change at the reaction between an analyte and a titration reagent is monitored by a thermistor. Break-response to the volume of an added titrant indicates reaching the end point of the titration. Subject of this work is to develop a method for the titrimetric determination of acids and bases with this detection method.
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Application of monosubstituted cyclodextrins in chiral separation of omeprazole by capillary electrophoresis
Dvořák, Aleš ; Čabala, Radomír (advisor) ; Coufal, Pavel (referee)
Chiral separation of omeprazole was the subject of this work. Five diferent monosubstituted derivatives of α- and β-cyclodextrins, two of them cationic and three anionics, were used as chiral selectors in various buffers of different pH. The influence of CD and buffer concentrations on chiral separation was studied. Voltage of 25 kV, UV detection in the range from 202 to 303 nm and constant temperature of 20 řC was used for all measurements. Concentration of CDs between 0 and 7 mmol.l-1 was used. Fused silica capillary of 50 µm ID and 375 µm OD, 48,5 cm total and 40 cm effective lenght was used as separation capillary. Dimethylformamide was used in stock solution of omeprazole as solvent, and was simultaneously applied as EOF marker. Succesfull chiral separation of omeprazole was achieved under the application of 2'-O-carboxymethyl-β-cyclodextrin (2'-CM-β-CD) and mono-6-deoxy-6-N,N,N',N',N'-pentamethylethylendiammonio- cyclomaltoheptaose dichloride (PEMEDA-β-CD) where the resolution of 1,42 (pH = 5,1) and 4,29 (pH = 11,1) was measured, respectively.
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Use of liquid chromatography in pharmaceutical analysis and preparation of monolithic stationary phases for thin-layer chromatography
Vojta, Jiří ; Coufal, Pavel (advisor) ; Tůma, Petr (referee) ; Jelínek, Ivan (referee)
(EN) In the first part of this work, analytical methods for determination of impurities of active pharmaceutical ingredients (API) in combined pharmaceutical dosage forms were developed and validated. Development of the methods covered both the optimization of sample preparation procedure and chromatographic conditions. The methods were validated according to International Conference on Harmonization guideline and both of them were confirmed to be able to analyze stability samples. Impurities in paracetamol, codeine phosphate hemihydrate and pitophenone hydrochloride in the presence of fourth API fenpiverinium bromide were separated by using ion-pair reversed phase chromatography with gradient elution. Symmetry C18, 250 x 4,6 mm, 5 µm heated to 35 řC was used as a separation column. A diode array detector was used. The detection wavelengths were set as follows: 220 nm for paracetamol impurity K, 245 nm for paracetamol and its other impurities and 285 nm for codeine, pitophenone and their impurities. Impurities in valsartan, amlodipine besylate and hydrochlorothiazide were separated by reversed phase UHPLC method with gradient elution. Chromatographic column Zorbax Eclipse C8 RRHD, 100 x 3,0 mm, 1,8 µm heated to 30 řC and spectrophotometric detection were used. The detection wavelengths were set as...
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Polymethacrylate monolithic columns in capillary liquid chromatography
Grafnetter, Jan ; Coufal, Pavel (advisor) ; Pacáková, Věra (referee) ; Ventura, Karel (referee) ; Sýkora, David (referee)
3 Conclusions This Thesis gives chromatographic and structural characteristics of the butyl methacrylate monolithic columns prepared for the capillary liquid chromatography. Results of this Thesis clearly demonstrate the possibility of preparation of capillary monolithic columns with a good repeatability of the principal chromatographic parameters. A completely new technique for preparation of the monolithic columns for use in the on-column detection mode was introduced. Different photometric detection modes were applied to monolithic capillary columns in CLC. The advantages and disadvantages of the on-column detection mode in comparison to the additional detection capillary were studied and described. It was shown that the best separation and the most sensitive quantification in the short analysis time could be reached by using the monolithic columns with detection window placed directry on the separation capillary, just after the stationary phase or within the monolith. The attempts leading to preparation of chiral monolithic stationary phases, which would allow enantioseparation of selected chiral analýes' were not totally successful. No time was left to find the suitable chromatographic conditions for enantioseparations. \ I
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Analysis, separation and physico-chemical characterization of peptide hormones by capillary electrophoresis
Šolínová, Veronika ; Jelínek, Ivan (advisor) ; Feltl, Ladislav (referee) ; Coufal, Pavel (referee) ; Samcová, Eva (referee)
I 11 CoNcr,usroNs The work bas demonstrated that capinary zone elechophoresis and micelrar electokinetic cbromatography are high-perfomrance and high-sensitive methods for qualitative and quantitative anďysis and for physico-chemicď characÚerization ofpeptide hormones. using the strategy for the rational selection of experimental conditions for cE analysis and separations ofpeptides, ionogenic peptides were separated as cations in the classical and isoelectric buffers in the acidic region, pH 2- 2'5, and as anions in amphoteric buffer in weakry arkaline conditions, pH = 8'1. Non-ionogenic peptides were analyzed by miceilar electrokinetic chromatography with micelrar phase consisting of anionic detergent sodium dodecylsulphate in alkaline conditions, pH 8.8. The experimental conditions were selected with the aim to avoid the adsorption of peptides on the capillary wall, which was particularly reached with suppression of dissociation of si'anol gÍoups on the imer capillary wall in the acidic pH region and with electrostatic repursion negatively charged peptides from negatively charged dissociation silanol groups on the inner capillary wall in the alkaline pH region. The pH values of background electrolýes were chosen in the region, where the biggest differences in calculated specific charges of analyzed...
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Post-column derivatization in HPLC for analysis of amino acids
Vaňkátová, Petra ; Coufal, Pavel (advisor) ; Sobotníková, Jana (referee)
Proteinogenic amino acids are the basic structural building units of proteins. Their analysis is important in many fields, especially in medicine. This thesis deals with one of the methods of derivatization of amino acids in order to increase their absorption in the UV - the post-column derivatization using copper (II) oxide. It is quick, robust and easy-to-use method. Following the nowadays trend in the analysis of free amino acids, this thesis is focused on the HILIC mode separation environment.
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