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Employment of HPLC in the field of drug analysis III.
Václavková, Jana ; Kovaříková, Petra (referee) ; Kučera, Radim (advisor)
Diploma thesis The use of HPLC in the analysis of drugs III Jana Václavková Charles Univerzity in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Chemistry and Drug Control High-performance liquid chromatography is one of the most progressive separative and analytical methods. Phases based on the oxide of zirconium with more advantageous chemical properties represent an alternative to classical stationary silica gel phases. The aim of this diploma thesis was to transfer the conditions of separation from the column ZirChrom® -PBD to the column Zirchrom® -MS and, thus, enable connection with the mass detector. During the separation, various types of buffer (diammonium hydrogen phosphate, ammonium acetate), concentrations of buffer, and constitutions of the mobile phase (solvents: acetonitrile, methanol) were used. For the separation of ondansetron and its five impurities, the following optimal conditions were found out: a mobile phase composed of acetonitrile and 5 mM ammonium acetate (pH 7), 0-4 min. (40 : 60, V/V), 4-5 min. (40→50 : 60→50, V/V), 5-21 min. (50 : 50, V/V), 21-25 min. (50→40 : 50→60, V/V). The analysis was carried out at the temperature of 40 řC and the flow rate of 0.5 mL min-1 . The detection was performed at the wavelength of 216 nm. The separation...
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Analytical determination of active compounds by liquid chromatography II
Raška, Martin ; Kovaříková, Petra (referee) ; Sochor, Jaroslav (advisor)
ANALYTICAL DETERMINATION OF ACTIVE COMPOUNDS BY LIQUID CHROMATOGRAPHY II. The Preliminary Study of SPME Master's Thesis Martin Raška Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Chemistry and Drug Control, Heyrovského 1203, Hradec Králové This thesis deals with the issue of analytical determination of active compounds by liquid chromatography. It's specifically focused on determination of benzodiazepines in biological material by using solid-phase microextraction (SPME) and high performance liquid chromatography (HPLC). HPLC is one of the most important chromatographic methods today. Its main advantages are sensitivity, selectivity and speed of separation and creation of reproducible record. SPME can be described as a simple and effective sample preparation technique integrating sorption, desorption and concentration of an analyte. This technique is solvent-free and requires no use of a complicated apparatus. Its basic principle is the exposure of liquid or fluid sample to a small amount of extraction phase. The following chromatographic conditions were proved to be optimal. Methanol:water (80:20) was used as a mobile phase with pH value adjusted to 7.5, flow rate was 0.8 ml/min and detection wavelength was 254 nm. Polydimethylsiloxane fiber...
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Analysis of selected polar compounds in HILIC mode
Brychová, Anna ; Vrbatová, Ivana (referee) ; Kovaříková, Petra (advisor)
Nowadays High Pressure Liquid Chromatography is the most important and the most frequently used separation technique that enables qualitative and quantitative analysis of the complex mixtures. One of its variants is Hydrophilic Interaction Liquid Chromatography. Lately this technique has experienced an increasing boom particularly, due to its ability to improve separation of very polar and hydrophilic compounds. The adeninribonucleotides (ATP, ADP, AMP, cAMP), creatine and phosphoceratine are among these highly polar compounds that are of great importance not only for human body. Number of analytical methods has been developed and published for the analysis of these compounds; however HPLC methods using the reverse phases have been dominated. The basic overview of these methods is a part of this diploma thesis. The experimental part of this thesis is focused on the development of chromatographic conditions suitable for the simultaneous analysis of ATP, ADP, AMP, cAMP, creatine and phosphocreatine in HILIC mode. The best separation was achieved on ZIC®-HILIC (150 x 2,1 mm; 3,5 μm; 200 Å) column using a binary mobile phase and gradient elution. The mobile phase consisted of the A component, (2 mM ammonium formate, pH 6,45) and the B component (90% of acetonitrile, 2 mM ammonioum formate) that were...
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The use of Infrared and Raman Spectrocopy for Preformulation Pharmaceutical Developmnet
Klimeš, Jiří ; Vrbatová, Ivana (referee) ; Kovaříková, Petra (advisor)
56/56 ABSTRACT THE USE OF INFRARED AND RAMAN SPECTROSCOPY FOR PREFORMULATION PHARMACEUTICAL DEVELOPMNET Mgr. Jiří Klimeš April 2010 Department of Pharmaceutical Chemistry and Drug Control; Pharmaceutical Faculty, Charles University in Prague Zentiva, k.s, Prague, Development Department, Laboratories of Solid State Analysis Within pharmaceutical preformulation development, we are interested in information which is helpful for drug product formulation. The properties expected from drug product are stability and suitability for manufacturing. All of these properties must be in accordance with therapeutic and regulatory requirements. For this purpose, there are many analytical methods used in the pharmaceutical industry that serve for investigation of stability, quality and possible interactions of active pharmaceutical ingredient with excipients. Accuracy, efficacy, and especially promptness and difficultness of analysis are the criteria for selection of a particular analytical method. Solid state methods are essential, just for their smart use and applicability to acquiring further characteristics of the sample, e.g. polymorphisms, size and particles distribution, which represent crucial knowledge, for formulation of final drug product and its properties. A survey at thedevelopment department in laboratories...
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Employment of HPLC in the field of Drug analysis I.
Kalafut, Peter ; Kučera, Radim (advisor) ; Kovaříková, Petra (referee)
Curcumin with it's derivates belongs to pharmacologically acting diarylheptanoids. They are obtained from the herbal rhizomes of genus Curcuma spp. (Zingiberaceae), which are widespread in tropical regions of south-east Asia. For last decades the drug has been in focus of scientists. On the human organism there have been proven many interesting effects. Therapeutically are used it's choleretic, antioxidant and antiinflammatory activities. Nowadays the interest orientates to the prevention and treatment of cancer and to the favourable influence on Alzheimer's disease. After oral administration, however, curcumin achieves the system circulation only in traces. In introduced study we developed HPLC method for the determination of curcuminoids. The most advantageous way is extracting the pigments from the herb or extract with methanol as relatively polar solvent. In the aqueous medium is practically unsoluble. The presence of three acid hydrogens exhibits in the alkaline aqueous solutions. The resultating ionisation is documented by color change from yellow to red. These conditions prejudice the stability of the substance - in part we may prevent the degradation by using the antioxidants and keeping in dark place. The analysis utilizes a reversed-phase C18 column and involves the use of an external...
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HPLC analysis of drug candidates from the group of aroylhydrazones II.
Stariat, Ján ; Kovaříková, Petra (advisor) ; Kučera, Radim (referee)
1. ABSTRACT High performance liquid chromatography (HPLC) is one of the most frequently used analytical techniques for the analysis of drugs. Although iron is a vital element, excessive amounts in the body are highly toxic. The search for highly selective and effective iron chelating agents has been mainly inspired by the need to mobilize iron from tissues that are chronically overloaded with iron. However, recent investigations focused on the possibility to use iron chelators for the treatment of many other pathologies. Salicylaldehyde isonicotinoyl hydrazone (SIH), a biocompatible iron chelator derived from aroylhydrazone, is under extensive investigation as a promising drug candidate. Besides ability to bind iron, it shows interesting pharmacological effects: antioxidative, antiproliferative, cardioprotective, antimalarical and antimicrobic. The aim of this study was to develop optimal HPLC conditions for the separation of SIH and its potential metabolites (isoniazide, acetylisoniazide, salicylaldehyde) and to apply the method to the study focused on the isolation of analytes from rabbit urine using SPE. The best chromatographic analysis was achieved on a HPLC column (Phenomenex 250 4.6 mm I. D.) packed with Prodigy 5u ODS3 100A (5 μm) as a stationary phase. The mobile phase was composed of methanol :...
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The alternative stationary phases in HPLC analysis of drugs
Holásková, Petra ; Kovaříková, Petra (referee) ; Kučera, Radim (advisor)
Rigorous thesis The Alternative HPLC Phases for Analysis of Pharmaceuticals Mgr. Petra Holásková Charles Univerzity in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Chemistry and Drug Control The solubility of silica gel at high pH is the cause for developing alternative HPLC columns based on metal oxides, such as titanium oxide, aluminium oxide, and zirconium oxide. Advantages of these columns are particularly high chemical stability and separation efficiency. In our project, zirconia-based stationary phases were tested in qualitative and quantitative analysis of doxazosine and its five impurities. Polystyrene-coated zirconia was chosen because of its low retention and appropriate selectivity. The separation was done within 16 min. Subsequently, chromatographic conditions were validated.
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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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Bioanalytical method development for the investigation of the role of pyridoxal isonicotinoyl hydrazone in isonazid intoxication
Effmertová, Marcela ; Kovaříková, Petra (advisor) ; Sochor, Jaroslav (referee)
High-performance liquid chromatography is one of the most frequently used separation methods for an analysis of drugs in biological material. It is suitable both for quantitative and qualitative drug analysis. Isoniazid is used for the treatment and a prevention of tuberculosis. Acute isoniazid intoxication is manifested by tonic-clonic convulsions. Vitamine B6 (pyridoxine) is used in clinical practice as an antidotum. Although this type of toxicity is considered to be associated with the deficiency of vitamine B6 (or its active form, pyridoxal-5-phosphate - PLP), description of mechanisms and processes, which are responsible for this effect, is still missing. The aim of this study was to develop suitable chromatographic conditions for monitoring intoxication by isoniazid and detection of potential hydrazone metabolites. These conditions should allow a separation of seven analytes (isoniazid, acetylisoniazid, pyridoxal, pyridoxol, pyridoxal-5-phosphate, and the o-108 - internal standard). Furthermore, the aim was to study possibilities of isolating all those substances from rabbit plasma. The best chromatographic separation was achieved using the HPLC column LiChroCART 250 × 4 nm I.D., packed with Lichrospher 100 RP-18 (5 µm). The mobile phase was composed of a buffer - component A (NaH2PO4 0.01 mol/l, with...
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