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Using of Micellar Electrokinetic Chromatography in the Analysis of Pharmaceuticals
Lípová, Markéta ; Polášek, Miroslav (referee) ; Pospíšilová, Marie (advisor)
In this work, micellar electrokinetic chromatography (MEKC) with UV detection at 214 nm was developed for separation of paracetamol, caffeine, ascorbic acid and chlorphenamin. The validated method was used for selective assay of the active substances in pharmaceutical preparation. The separations were optimised by examining a number of experimental conditions, such as the electrolytic system type and concentration, pH, concentration of sodium dodecyl sulphate (SDS), addition of organic solvents, separation voltage and temperature. The optimal operational system consisted of 40mM boric acid, 70mM SDS and 10% (v/v) of methanol (adjusted to pH* 7.6 with 1 M ammonia solution). Ethylparaben was chosen as an internal standard. The assay of compounds analysed was carried out at 30 kV and 20ř C with 60 cm x 75 µm I.D. fused silica capillary (effective length 50 cm). A single analysis took less than 10 min. The method was suitable for determining the drugs in pharmaceutical preparation TRIGRIP capsules with RSD values from 1,23% to 2,75% (n=3). The MEKC results agreed well with nominal contents of the compounds. The recovery of the method ranged from 90.43% to 99.59%.
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Analysis of Calcium Pantothenat, Methylparaben and Propylparaben by Micellar Electrokinetic Chromatography
Balcar, Josef ; Polášek, Miroslav (referee) ; Pospíšilová, Marie (advisor)
1. ABSTRACT 1.1. ANALYSIS OF CALCIUM PANTOTHENAT, METHYLPARABEN AND PROPYLPARABEN BY MICELLAR ELECTROKINETIC CHROMATOGRAPHY Josef Balcar Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Analytical Chemistry, Heyrovského 1203, Hradec Králové In this study, a new micellar electrokinetic chromatography (MEKC) has been developed for the simultaneous analysis of calcium pantothenat, methylparaben and propylparaben. Separations were carried out in a fused silica capillary (7,5 cm × 75 μm i.d.) at 20 kV with UV detection at 200 nm. The optimal background electrolyte was 40 mM tricine buffer (pH* 8.2) containing 50 mM sodium dodecyl sulfate as a surfactant and 20 % (V/V) methanol. Rectilinear calibration ranges were 50.0 - 500.0 mg/100ml for calcium pantothenat, 2.0 - 20.0 mg/100ml for methylparaben and 0.5 - 5.0 mg/100ml for propylparaben. The validated MEKC method was applied to the determination of the analytes in a pharmaceutical preparation. The total analysis time was <3 min.
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Assay of Glucosamine in Pharmaceuticals and Nutraceuticals by Capillary Isotachophoresis
Elsnerová, Lenka ; Polášek, Miroslav (referee) ; Pospíšilová, Marie (advisor)
Capillary isotachophoresis (ITP) with conductivity detection has been used for separating and determining of glucosamine (GA) from the SYSADOA group (symptomatic slow acting drugs of osteoarthritis). The optimised ITP electrolyte system consisted of 10 mM potassium picolinate and 10 mM picolinic acid (pH 5.4) as the leading electrolyte (LE) and 10 mM formic acid (pH 3.0) as the terninating elektrolyte (TE). The driving and the detection curents were 50 µA (for 340 s) and 10 µA, respectively. A single analysis took ˂ 10 min. Under the optimum conditions the effective mobility of GA was determined as 24,7 x 10-9 m2 .V- ¹s- ¹ when using tetraethylamonium-iodide as the standard of the mobility. The calibration graph was rectilinear in the range 50 - 200 mg.l-1 of GA with r2 = 0,99747. The RSD was 0,52 % (n=6) when determining 100 mg.l-1 of GA. The ITP method was applied to the assay of GA content in various pharmaceuticals and nutraceuticals. Acceptable accuracy of the method was confirmed by the added/found GA recovery experiments (recoveries from 96.2-100.3%).
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Analysis of plant extract of Orthosiphon stamineus by capillary zone electrophoresis
Hašek, Jan ; Polášek, Miroslav (referee) ; Pospíšilová, Marie (advisor)
Capillary zone electrophoresis with UV detection at 200 nm was developed for the determination of four phenolic acids and four flavonoids in plant material. The electrophoretic behavior of phenolic compounds was investigated to optimize their separation as a function of buffer pH, buffer concentration. A 50m mM borate buffer, pH 9 was found most favorable. The separation was obtained with fused-silica capillary column (50 cm x 50 μm I.D.) an applied voltage of 25 kV and a temperature of 25řC. For increase injection volume and decrease the detection limits was performed by applying Large-volume sample stacking with polarity switching. The limits of detection were between 0,006 and 0,014 μg/ml. The method was used to determine these compounds in methanolic extract of Orthosiphon stamineus leaves that contained 710,9 μg g-1 pulverized drug of rosmarinic acid and 38,2 μg g-1 of caffeic acid. About a 60- fold enhancement in senzitivity, relative to a conventional injection, was demonstrated in a real sample.
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Analysis of natural compounds by capillary isotachophoresis and capillary zone electrophoresis.
Černá, Veronika ; Polášek, Miroslav (referee) ; Pospíšilová, Marie (advisor)
It has been designed tITP - CZE method with a reversed electro-osmotic flow for the analysis of seven organic acids of natural origin. It was monitorated the effect of boric buffer concentration, pH effect, the addition of organic solvent, the addition of cyclodextrin, concentration of NaCl as a stacker, and injection time. Measurements were made in voltage - 30 kV in capillary with inner diameter 50 μm and effective length 68 cm. Optimum separation conditions were found at a concentration of 125mM boric buffer, pH 8,2, the addition of 0,001% hexadimethrinbromid and addition of 10mM and 2,6-di-O- methylcyklodextrin. The stacker was used at a concentration of 200mM NaCl and injection time was 90 s. Intracapillary thermal gradient from 20o C to 24řC during electrophoresis has yielded improved resolution for the analytes.
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Separace chirálních pesticidů pomocí cyklodextrinů kapilární elektroforézou
Denková, Barbora ; Polášek, Miroslav (referee) ; Jáč, Pavel (advisor)
In this diploma thesis, a preliminary study on the applicability of EKC-PF (with CD as chiral selector) to the separation of chiral pesticides was performed. In introduction, theoretical informations are presented concerning electrophoresis instrumentation and theory as well as different electrophoresis modes. Then, enantiomeric separation is introduced through cyclodextrins and possibilities of partial filling mode to finally terminate with a definition of chiral pesticides and some information about their enantioseparation. Concretely, in the experimental part, the evaluation of enantioresolution of several chiral pesticides (trichlorphon, cyproconazole, hexaconazole, imazalil, myclobutanil, penconazole, tebuconazole, propiconazole, and benalaxyl) using CM-β-CD as chiral selector was performed. First of all, a univariate optimization of variables (CM-β-CD injection time, voltage, temperature, pH, and buffer nature and concentration) was carried out for benalaxyl. Finally a screening, involving the effect of the CM-β-CD injection time, was performed for the other pesticides to check the potential of this CD as chiral selector.
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Analysis of diosmin, hesperidin and rutin in nutraceuticals by capillary electrophoresis
Vašíčková, Tereza ; Polášek, Miroslav (referee) ; Pospíšilová, Marie (advisor)
Analýza diosminu, hesperidinu a rutinu v potravních doplňcích metodou kapilární elektroforézy 5/82 Abstract A method based on capillary zone electrophoresis (CZE) with UV detection was developed for simultaneous separation and determination of flavonoids rutin, hesperidin and diosmin. The analysis was performed in a fused-silica capillary with effective length 50 cm, i.d. 50 µm, voltage - 30 kV and 25 o C. UV detection was used at 200 nm, 246 nm and 280 nm. The samples were loaded hydrodynamically at a pressure of 50 mbar for 6 s. A single analysis took less than 6 minutes. The separation was optimized by examining a number of experimental conditions, such as concentration of the electrolytic system, pH, addition of organic solvents and cyclodextrins. The optimal background electrolyte consisted of 35 mM natrium tetraborate with 2.5% of methanol (adjusted to pH* 9.0 with boric acid) and 1.5 mM α-CD. The calibration graphs were linear for both rutin (100.58 - 1005.80 µg/ml; r = 0.9991), hesperidin (90.33 - 903.29 µg/ml; r = 0.9785) and diosmin (45.56 - 455.60 µg/ml; r = 0.9972). Propylparaben was chosen as the internal standard. The method was applied to the assay of the flavonoids in a nutraceutical HEMOSTOP® PROBIO, capsules and characterized by RSD 3,25% (rutin), 4,12% (hesperidin) and 3,98% (diosmin), n...
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Vývoj umělého zubu založený na technice povrchové plasmové resonance
Solanská, Kateřina ; Polášek, Miroslav (referee) ; Solich, Petr (advisor)
For development an artificial tooth hydroxyapatite nanoparticles solution was electrophoretically deposited on the gold chip. It was established that experimental conditions of solution preparation, electrically field have marked effect to thickness of the hydroxyapatite layer. By this way was prepared chip suitable for SPR measurements. In the firs step the bovine serum albumin (BSA) was chosen as the model protein shows absorption on the hydroxyapatite layer. Further the native saliva and artificial saliva were used for pellicle forming. Samples of saliva showed difference between binding behaviors on the hydroxyapatite layer. The application of chlorhexidingluconate pharmaceuticals on the pellicle shows increase in thickness but rinsing with native saliva disclosed that the components of chlorhexidingluconate pharmaceuticals can be easily removed from the surface.
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Chemiluminiscenční hodnocení celkové antioxidační kapacity potravin
Vlčková, Jitka ; Solich, Petr (referee) ; Polášek, Miroslav (advisor)
Diplomová práce 2009 Abstract_ENG Jitka Vlčková ABSTRACT An investigation presented was concern to measure and evaluate the total antioxidant capacity (TAC) in samples of red wine clarified with four fining agents (polyvinylpolypyrrolidone and three different types of gelatin). All wine samples were treated by concentrations of 10, 20 and 40 g/hL of finings. The main aim was to discover how the particular agents in different dosages influence the TAC. The second part describes relations between changes in TAC in content of single antioxidant components (total polyphenols, anthocyanins, gallic acid and simple phenols). Total antioxidant capacity in red wine samples was evaluated using the Trolox equivalent antioxidant capacity assay (TEAC). A theoretical part of the thesis briefly summarizes basics about luminescence, focused on chemiluminescent reaction. Theory of free radicals and antioxidants, especially those included in red wine are also described. Process of winemaking aimed at fining is also contained in this part. An experimental part describes techniques of determination of the total antioxidant capacity, principle of chemiluminescent assay based on the luminol/peroxidase system. The results show the different behaviour of gelatin from the polyvinylpolypyrrolidone (PVPP). In general gelatin tends to...
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