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Validation of HPLC Method for Determination of some Vitamins in a Multivitamin Product
Stehlíková, Kristýna ; Mokrý, Milan (advisor) ; Kastner, Petr (referee)
Charles University in Prague Faculty of pharmacy in Hradec Králové Department of pharmaceutical chemistry and drug analysis Candidate: Mgr. Kristýna Stehlíková Consultant: RNDr. Milan Mokrý, CSc. Title of Thesis: Validation of HPLC method for determination of some vitamins in a multivitamin product. A method for simultaneous determination of concentrations of vitamins B1 (thiamine), B3 (nicotinamide), B6 (pyridoxine) and vitamin C (ascorbic acid) in a multivitamin product by means of HPLC was validated. Linearity, precision (carried out as repaetibility), accuracy, specificity and robustness were used as validation parameters. Linearity was carried out with the assistance of method of dilution of standard solutions of vitamins in range 50 - 150% of expected concentrations of particular vitamins. Solution of a multivitamin was prepared six-times for the precision experiment and then relative standard deviation was calculated. The relative standard deviation stayed in the range of 0.9 -1,61%. Accuracy was verified by analysis of model samples prepared by addition of known amount of particular vitamins to placebo. Yield varied between 97-105%. During the specificity experiments it was not found any interefence among the other compounds presented in the multivitamin product. Necessity of keeping given...
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Development of stability indicating method for chosen preparation
Chmurová, Klára ; Kastner, Petr (advisor) ; Mokrý, Milan (referee)
1 Abstrakt Development of stability indicating method for chosen preparation(HPLC determination of benzyl alcohol in vaginal cream) Graduation thesis Klára Chmurová Charles University in Prague, Pharmaceutical Faculty in Hradec Králové, Department of Pharmaceutical Chemistry and Drug Control The task was to find out a method of simultaneous determination of benzylkalcohol and imidazol (decomposition product of main substance of cream - clotrimazole). This thesis is intent on determination of benzylalcohol. We were looking for proper modification of the pharmaceutical preparation (vaginal cream), then optimisation of chromatographic conditions and validation of this HPLC method also. The best results were obtained with LiChrosphere RP 18,5 µm column (125 mm x 4,6 mm, SUPELCO, ), methanol : buffer (solution of 250 ml water, 1,05 ml triethylamine and 0,333g natrium hexasulphonate, pH = 7, set up by 85% H3PO4) 30 : 70 (v/v) was used as the mobile phase, flow rate was 1 ml/min. Detection was realised by UV detector with wave length set up on 223 nm. Time of analysis was shorter than 10 min.
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Lipophilicity determination of pyrazine
Balíková, Svatava ; Kastner, Petr (advisor) ; Pilařová, Pavla (referee)
Lipophilicity determination of pyrazine chalcone derivatives Degree paper Svatava Balíková Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Chemistry and Drug Control, Heyrovského 1203, Hradec Králové The lipophilicity (RMW) of 1,3-diphenylprop-2-en-1-one derivatives and 3-phenyl-1-pyrazin- 2-ylprop-2-en-1-one derivatives has been determined by reversed-phase thin-layer chromatography. RP-TLC experiments were carried out with tetrahydrofurane - phosphate buffer (pH 7,0) mobile phase, RMW values were obtained by extrapolation of RM valules (determined by RP-TLC) to tetrahydrofurane-free conditions. The influence of various substituents on RMW values was investigated. Furthermore the correlation between a RP-TLC retention parameter RMW and various calculated log P values was investigated in the series of 3-phenyl-1-pyrazin-2-ylprop-2-en-1-one derivatives. Highly significant correlation was found between RMW values and calculated log P values.
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HPLC Evaluation of L-Tryptophan and Its Metabolites in Biological Material
Málková, Kateřina ; Kastner, Petr (advisor) ; Pilařová, Pavla (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Kateřina Málková Supervisor: PharmDr. Petr Kastner, Ph.D. Title of thesis: HPLC evaluation of L-tryptophan and its metabolites in biological material The purpose of this thesis was to develop optimized conditions for determination of L-tryptophan and its metabolites (L-kynurenine, kynurenic acid, serotonin, 5-hydroxyindole-3-acetic acid, melatonin) using high performance liquid chromatography. Separation was achieved by a silica gel column Kinetex EVO C18 (100A, 150 × 3 mm, 5 μm) with guard column OPTI-GUARD 1 mm C18 using spectrophotometric and fluorimetric detection. Initial parameters of detection mentioned in the method were for kynurenine (absorbance at 369 nm, 227 nm and fluorescence detection Ex: 369 Em: 475). Detection and elution parameters of the method were further optimized for subsequently added analysed substances on the basis of their individual UV and fluorescence spectra. Different types of mobile phase, different pH of buffer were examined. The finally mobile phase consisted of two components: mobile phase A: water + acetate buffer 0,1 M; pH 4,5; methanol in a ratio 97:3 mobile phase B: methanol. The separation was performed by gradient...
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Use of liquid chromatography in pharmaceutical analysis III.
Babinská, Agáta ; Pilařová, Pavla (advisor) ; Kastner, Petr (referee)
Charles University in Praque, Faculty of Pharmacy in Hradec Králové Department: Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Agáta Babinská Tutor: PharmDr. Pavla Pilařová, Ph.D. Name of Degree Paper: Use of liquid chromatography in pharmaceutical analysis III. The purpose of this thesis was bioanalytical evalution of quetiapine and its two biologically active metabolites 7-hydroxyquetiapine and norquetiapine using High Performance Liquid Chromatagraphy. Separation was performed on zirconia reversed-phased column ZirChrom®-PBD (150x4,6 mm, 5 µm). The retention behaviour of those three analytes was examined at different types of mobile phase, changing strenght and pH of buffer and changing levels of organic compound (ACN) in eluent. The finally mobile phase consisted of two components: MF A - acetate buffer, 6mM, pH 4,0:ACN in a ratio 90:10 (v/v) MF B - 10mM trifluoroacetic acid, pH 1,9:ACN in a ratio 40:60 (v/v) The flow rate was 1 ml/min, the temperature was set at 30řC. The detection was carried out at 254 nm. The separation was performed by gradient elution. The analytes were isolated from plasma using LLE. LLE was validated according to FDA and ICH. Flunitrazepam was used as the internal standard. Specificity, accuracy, precision, recovery, linearity,...
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Modification of the capillary wall for the separation purpose I.
Blažková, Andrea ; Kučera, Radim (advisor) ; Kastner, Petr (referee)
Department of Pharmaceutical Chemistry and Drug Analysis Andrea Opavská doc. PharmDr. Radim Kučera, Ph.D. Modification of the capillary wall for the separation purpose I In general, capillary electrophoresis is a separation method suitable for the analysis of charged molecules, eventually neutral substances. The interest in this method and its further modification (e.g. capillary electrochromatography) has been increasing in recent years, is developing. In the case of capillary electrochromatography, the development focuses mainly on the modification of the inner wall of the capillary. The purpose of this modification is in particular to introduce a stationary phase that would improve selectivity, as well as the modification of the electroosmotic flow. The thesis deals with the modification of the internal capillary wall and the subsequent testing of the prepared capillary. One possibility is chemical coating. The second tested method is called Layer-by-Layer and represents the layering of variously charged substances in layers interacting with each other through electrostatic forces. In our work we used polycation poly(diallyldimethylammonium chloride) and graphene dispersion. The choice of graphene is very advantageous because it has excellent adsorption properties due to its morphological...
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Evaluation of the chosen active substance in the preparation by UHPLC II.
Husáková, Šárka ; Kastner, Petr (advisor) ; Mokrý, Milan (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Drug Control Candidate: Šárka Husáková Supervisor: PharmDr. Petr Kastner, Ph.D. Title of thesis: Evaluation of the chosen active substance in the preparation by UHPLC II. Method for the determination of sodium picosulfate monohydrate, its related substances and sodium benzoate using ultra high performance liquid chromatography (UHPLC) was validated. This method has been transmitted from the conditions of previously validated and optimized high performance liquid chromatography (HPLC) method. Separation of the substance was achieved with Kinetex® 2.6 micron C18, 100A, 150 x 3.00 mm, 2.6 microns column using UV detection at a wavelength of 263 nm. The mobile phase consisted of buffer, acetonitrile and propan-2-ol in a ratio of 55: 43: 2 (v/ v/v). The buffer contained sodium dihydrogen phosphate, cetyltrimethylammonium bromide and water. The pH 7.0 of the buffer was achieved by phosphoric acid. The column temperature was 40 ř C, injection volume 3 μl, the flow rate was set at 0.5 ml/min. The method was evaluated as sufficiently selective, precise, exact, linear and sensitive. Furthermore robustness was tested according to the Plackett-Burman design. It was found, that the acetonitrile volume...
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