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Employment of gas chromatography in the field of drug analysis III.
Šináklová, Barbora ; Kučera, Radim (advisor) ; Vrbatová, Ivana (referee)
Diploma thesis Employment of gas chromatography in the field of drug analysis III. Barbora Šináklová Charles Univerzity in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Chemistry and Drug Control The gas chromatography represents a sensitive analytic method. Effective and fast separation of complicated compounds and manipulation with small amounts of samples using a relatively simple equipment characterise the GC method in particular. Butan-1,3-diol is a substance used in chemical industry as a solvent and a carrier of aromatic substances, or for plastics and explosives production. It is added to antifreeze mixtures in radiatores. Another usage possibility constitute cosmetic products, the substance also occurs in pesticides. Because of its antimicrobial effects, butan-1,3-diol is added to cleansing articles. It extends the effect of certain syringe articles and increases the effect of dissolved effective substances. This method was used in this diploma thesis to determine the volume of butan-1,3-diol and the method was validated. The work was realized with gas chromatograph Shimadzu GC-2010 with flame- ionization detector. Hydrogen was chosen as the carrier gas. Supelcowax TM-10, Fused silica capillary column, 30 m × 0,53 mm × 0,5 µm was used. The inner standard...
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HPLC analysis of dexrazoxane and its metabolites
Dlouhý, Lukáš ; Kovaříková, Petra (advisor) ; Kučera, Radim (referee)
High performance liquid chromatography (HPLC) is one of the most used separating methods of instrumental analysis enabling both qualitative and quantitative analysis of substances. Anthracyclines are cytotoxic drugs widely used in clinical practice for treatment of hematological malignancies (leucaemias, lymphoms) and solid tumours (stomach, breast, ovarian cancer). Treatment by these drugs has a serious limiting factor, however. This factor is an anthracycline induced cardiotoxicity, which is caused by hydroxyl radicals and other reactive oxygen forms. The main role in their formation play the complexes with iron. Dexrazoxane is a derivate of bisdioxopiperazine, which is used to reduce the cardiotoxic effect of anthracyclines. It is supposed that it takes effect by the means of its active metabolite ADR-925, which works as a substance chelating iron. This mechanism hinders the iron dependant formation of oxygen radicals. This thesis deals with analysis options of dexrazoxane and its hydrolysis products/metabolites on the stationary phase Ascentis HILIC in conditions compatible with mass spectrometric detection (MS). The best results were achieved in conditions of isocratic elution using mobile phases containing 5 mM ammonium formiate with pH 5 or 7 and acetonitrile in ratio 22:78 (v/v). Mobile...
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Analytical evaluation of novel drug candidates from the group of iron chelators using HPLC II.
Tomalová, Kateřina ; Kovaříková, Petra (advisor) ; Kučera, Radim (referee)
High performance liquid chromatography (HPLC) has a dominant position among the modern techniques in both the qualitative and quantitative drugs analysis. After adequate sample preparation it is also commonly used for the determination of drugs and metabolites in biological material. This study is focused on the development and validation of a chromatographic method suitable for the analysis of 2',4'-dihydroxyacetophenon isonicotinoyl hydrazone (DHAP-INH) - a novel biocompatible iron chelator, and its application for stability evaluation of this drug candidate in rabbit plasma in vitro. DHAP-INH is among newly synthesized salicylaldehyde isonicotinoyl hydrazone (SIH) analogues, which were prepared to improve compound stability in plasma and thus make pharmacokinetic profile of aroylhydrazones more favorable. Sufficient separation of DHAP-INH, its synthetic precursors/degradation products (2,4-dihydroxyacetophenon and isoniazide) and internal standard (SIH) was achieved on LiChrospher 100, RP-18 column (250 mm × 4,6 mm ID, 5 mm) employing a mobile phase composed of a mixture of phosphate buffer (0.01 M NaH2PO4.2H2O; 2 mM EDTA; pH 6,0) and methanol in a ratio of 54:46 (v/v). UV detection was performed at 254 and 326 nm. Different organic solvents were tested as precipitation agents, however...
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Potentiometric determination of ibuprofen.
Šrámková, Ivana ; Kastner, Petr (advisor) ; Kučera, Radim (referee)
Potentiometric determination of ibuprofen Thesis Ivana Šrámková A development of a selective electrode for potentiometric determination of ibuprofen in pharmaceutical formulations was aimed in this work. Several sensors were constructed. Their response to the ibuprofen was under study. It was revealed that a choice of appropriate membrane components as well as the molar ratio of them is of high importance for an ibuprofen-selective sensor. Some of the tested sensor's response is close to the Nernstian response. The best results were achieved using HP-β-CD with the function of an ionophore, 2- phenyl-2-nitrophenyl ether as a solvent mediator and tetrahexylammonium bromide as lipophilic specie. It was found that one of the evaluated electrodes is potentially iodide- selective. The ibuprofen-selective electrode with the best features is still under study.
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Employment of gas chromatography in the field of drug control I.
Holeksa, Miroslav ; Kučera, Radim (advisor) ; Sochor, Jaroslav (referee)
1. ABSTRACT Ethylenoxide is a volatile gas, used for medical instrument sterilization in hospital, which can not stand heat sterilisation. Ethylenoxid is a cancerogenic and a mutagenic substance and for that reason there are put high demands on residual content in instruments after sterilization. Optimalization of chromatographic conditions was realized in this diploma thesis. Gas chromatograph Shimadzu GC-2010 and PC with chromatographic software GC solution Analysis Ver.:2.21 were used. Restek Rtx®-1 (100% dimethylpolysiloxan), 30 m, 0,32 mm; 1 µm column was used. Carrier-gas (He) flow rate was 1,05 ml/min. Particular conditions for chromatographic determination were optimalised in succesive steps (suitable solvent, thermostating time period and temperature, gas syringe temperature and sample volume). Following conditions of headspace analysis were choosen. Headspace vial thermostating time 30 minutes, temperature 90řC, gas syringe temperature 60řC and DMSO as a solvent. Calibration curve was construed to determinate ethylenoxide content. Its equation is y = 1620x - 6,627 (R2 = 0,999). Before analysis, particular ethylenglycol samples were appropriately modified and injected onto column. Content of ethylenoxid, determined in three samples by calibration curve, was matched to the limit of ethylenoxide...
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i>Employment of HPLC in the field of Drug analysis I.
Radová, Lucie ; Kučera, Radim (advisor) ; Pilařová, Pavla (referee)
8 ABSTRACT This work reports on study of sample stability of omeprazole during chiral analysis. The attention has been paid to the influence of experimental conditions (sample solvent, storage temperature, influence of light) on the stability of (R,S)-omeprazole and (S)-omeprazole as well. . The experimental results have shown that the most suitable solvent is acetonitrile for both i.e. racemic mixture and S-enantiomer. Column temperature and light are important variables, which influence stability of omeprazole during analysis. A decrease of column temperature results in an increase of omeprazole stability. S-enantiomer is more stable in comparison with racemate. An action of light on the solutions results in an decrease of its stability, S-enantiomere is on the light less stable in comparison with racemate.
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The employment of HPLC in the field of drug analysis IV.
Krejčí, Tereza ; Kučera, Radim (advisor) ; Kovaříková, Petra (referee)
Employment of HPLC in the field of drug analysis IV. Diploma thesis Tereza Krejčí Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Chemistry and Drug Control Heyrovského 1203, Hradec Králové. The diploma thesis is targeted to usage of High Performance Liquid Chromatography in the field of Quality control of drug substances. Methylergometrine is a derivative of ergometrine that belongs to Ergot alkaloids. These native origin substances have strong pharmacological effects on different human body systems already in low concentrations. Active components from ergot are acquired by extraction and subsequent separation of individual components from a mixture. These substances are repurified. It is very expensive to produce totally pure substances and thus final substances may contain defined amount of impurities. In case of methylergometrine Related substances are analysed according to the valid European pharmacopoeia. Nine substances are in the specification of possible analysed components, tenth component (-)methylergometrinine has not been described in the pharmacopoeia so far. This thesis deals with development of chromatographic conditions for qualitative separation of a mixture of methylergometrine and its impurities on zirconia based stationary...
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The employment of HPLC for separation of bioconjugates of azaphtalocyanines
Kaminská, Marta ; Kučera, Radim (advisor) ; Pilařová, Pavla (referee)
Diploma thesis The employment of HPLC for separation of bioconjugates of azaphtalocyanines Marta Kaminská Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Chemistry and Drug Control This diploma thesis deals with development of suitable chromatographic conditions for separation of bio-conjugates of azaphthalocyanines. These compounds are of great interest today, they might be useful as potential quenchers of fluorescence in molecular probes. The experiments were carried out in analytical and semi-preparative scale. Nine C18 chromatographic columns were tested. The conditions for analytical and semi-preparative chromatography were optimized. The following chromatographic conditions for separation of bio-conjugates of azaphtalocyanines were found (analytical method): Stationary phase : Hypersil BDS, 100 × 4,6 mm, 3 μm particle size Mobile phase A : 50 mM water solution TEAA in 12 % acetonitrile; Mobile phase B : acetonitrile; Gradient elution. Other conditions : column temperature 40 řC, flow rate 1 ml per minute Detection 254 nm, 374 nm, 552 nm, 673 nm The following chromatographic conditions for separation of bio-conjugates of azaphtalocyanines were found (semi-preparative method) : Stationary phase : Hypersil BDS 250 × 4,6 mm, 5 μm...
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