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Potenciometrické stanovení gentamycinu ve farmaceutických přípravcích
Kočí, Martina ; Pospíšilová, Marie (advisor) ; Polášek, Miroslav (referee)
Gentamicin is an aminoglycoside antibiotic, and can treat many types of bacterial infections, particularly Gram-negative infection. It is one of the heat-stable antibiotics that remain active after autoclaving, which make it particularly useful in the preparation in the certain microbiological growth media. Traditionally, pharmaceutical analysis of these compounds relies heavily on chromatography, yet also frequently requiring the use of reagent-based detection principles like spectrophotometric, chemiluminescent detection in flow-injection analysis , capillary electrophoresis, a novel LC/ELSD, thin-layer chromatography, HPLC.A simple and sensitive potentiometric procedure for the determination of gentamicin is presented, after development of selective electrodes based on PVC membranes using different type of cyclodextrins and its derivatives, or Evans Blue complex with gentamicin as ionophers. Several mediator solvents and lipophilic ionic species were also used in order to optimize the characteristics of the membranes. The evaluation of the general characteristics for all the units prepared revealed an analytical linear range of about 2x10-4; 5x10-3 mol L-1, slopes of about 50 mV/dec, good reproducibility and low response times. The evaluation of Potentiometric selectivity coefficients will permit to...
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HPLC analýza makrolidových a tetracyklinových antibiotik v nemocničních odpadních vodách
Vrubl, Jaroslav ; Solich, Petr (advisor) ; Polášek, Miroslav (referee)
Analysis of macrolides and tetracyclines in hospital wastewaters by HPLC ABSTRACT Macrolide and tetracycline antibiotics are drugs used for treatment and prevention of infectional illnesses both in human and veterinary medicine. As other environmental contaminats, they can accumulate in environment and induce adverse effects in terrestrial and aquatic organisms. and induce bacterial resistance. The sensitive analytical methods are necessary to quantify their level in wastewaters to rate the risk caused by their presence in environment. The HPLC with MS detection is method mostly used to analysis, because of its high sensitivity. A method using UV or fluorescence detection was tried to be developed as an alternative to HPLC-MS. A method to analyse macrolide using Hichrom Lichrosorb RP 18, 250 x 4.6 mm i. d. and Chromolith Performance column RP 18e, 100 x 4.6 mm i. d. were used. A mobile phase ACN: 0.05M KH2PO4 (pH 7.5) 30:70 (v/v) was used, the detector was set at 215 nm. The method using pre-column derivatization by FMOC-Cl was studied. The analysis was performed on Chromolith Performance column RP 18e, 100 x 4.6 mm i. d. The fluorescence detector was set at excitation wavelength 255 nm and emission wavelength 315 nm. The method to analyse tetracyclines used gradient elution of ACN and 0.02 M oxalic acid....
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Charakterizace kořenových exsudátů pomocí HPLC
Flutková, Kateřina ; Polášek, Miroslav (advisor) ; Solich, Petr (referee)
Root exudates from germinated English grass seeds were analyzed by HPLC with UV detection (210 nm) in the first part of this thesis. Column Acclaim OA 4 x 150 mm, Dionex was used, temperature was ambient and as a mobile phase served 100 mM sodium sulphate (pH 2.65) with flow rate 0.6 ml/min. Injection volume was 40 μl, the measurement run under isocratic conditions. Standards were solutions of oxalic, tartaric, formic, malic, iso-citric, lactic, acetic, citric, succinic, fumaric, cis-aconitic and trans-aconitic acid and their mixture. Chromatograms from these measurements were compared to one another and with regard to literature it was gathered from, that oxalic and tartaric acid and maybe malic and acetic acid is present in the exudates. This supposition was proved by HPLC with diode-array detector. The second part of this work consisted in analyses of samples of root exudates by means of HPLC with diode-array detection with possibility of gradient elution. Column ProntoSIL 250 x 3 mm, Bischoff was used, temperature was ambient and the mobile phase was 50 mM ortho-phophoric acid with flow rate 0.7 ml/min. Volume 10 μl was injected. Solutions of oxalic, tartaric, malic, acetic, citric and fumaric acids and their mixture were used as standards. Absence of any of supposed acids in samples was concluded after...
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Determination of glucosamine by capillary zone electrophoresis with contactless conductivity detection
Los, Petr ; Polášek, Miroslav (advisor) ; Pospíšilová, Marie (referee)
7.1.2. Determination of glucosamine using capillary zone electrophoresis with conductivity contactless detection A novel CE method with contactless conductivity detection suitable for the determination of glucosamine and K+ in pharmaceuticals was devised. Under the optimum conditions (aqueous 30 mM acetate buffer of pH 5.2 as the background electrolyte; voltage 30 kV; 25 řC) glucosamine (migrating as glucosaminium cation) was well separated from K+ that could occur in the dosage forms as excipient. The CE analysis was performed in fused-silica capillaries (50 μm i.d., 75 cm total length, 27 cm to detector) and the separation took < 3 min. The calibration graphs were linear for both glucosamine (100 - 300 μg/ml; rš = 0.997) and K+ (15 - 75 μg/ml; rš = 0.997) when using ethanolamine (100 μg/ml) as the internal standard. The LOD values (S/N = 3) were 9.3 μg/ml for glucosamine and 2.9 μg/ml for K+. The method was applied to the assay of glucosamine content in various dosage forms. Intermediate precision evaluated by determining the content of glucosamine in a single formulation on 3 consecutive days was characterized by RSD 2.35% (n=15). Acceptable accuracy of the CE method was confirmed by the added/found glucosamine recovery experiments (recoveries 94.6-103.3%) and by statistical comparison of the results...
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Optimization of the Determination of Septonex in Pharmaceutical Preparations by Capillary Zone Electrophoresis with Use of Organic Solvents as Additives in the Background Electrolyte
Šindelková, Martina ; Pospíšilová, Marie (referee) ; Polášek, Miroslav (advisor)
OPTIMIZATION OF THE DETERMINATION OF SEPTONEX IN PHARMACEUTICAL PREPARATIONS BY CAPILLARY ZONE ELECTROPHORESIS WITH USE OF ORGANIC SOLVENTS AS ADDITIVES IN THE BACKGROUND ELECTROLYTE A new method of capillary zone electrophoresis with contactless conductivity detection for the determination of septonex in pharmaceutical preparations was devised. Optimal conditions for the separation and determination of septonex were: background electrolyte 30mM MES of pH 7.0 (adjusted with 200mM TRIS) containing 12.5mg/ml of (2- hydroxypropyl)-β-cyclodextrin and 20% (volume), voltage 25kV, temperature 25řC and sample injection for 6 seconds under the pressure of 50mbar. Arginin (200µg/ml) was used as internal standard. The peak of septonex was satisfactorily separated from the peak of internal standard as well as from the EOF. The analysis was carried out in a fused-silica capillary (internal diameter 50μm, total length 75cm and the length to the detector 45cm). The separation took less than 5 minutes and the overall analysis time involving appropriate rinsing of the capillary was less than 13 minutes. The calibration curve was linear in the range 75µg/ml - 400µg/ml of septonex, correlation coefficient r = 0.9997. The LOD was 13,5μg/ml and LOQ was 45μg/ml of septonex. The method is applicable for qualitative as...
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Determination of Paracetamol, Ascorbic Acid and Phenylephrine in Pharmaceutical Preparations by Micellar Electrokinetic Chromatography
Kubíková, Drahomíra ; Polášek, Miroslav (referee) ; Pospíšilová, Marie (advisor)
DETERMINATION OF PARACETAMOL, ASCORBIC ACID AND PHENYLEPHRINE IN PHARMACEUTICAL PREPARATIONS BY MICELLAR ELECTROKINETIC CHROMATOGRAPHY Author: Kubikova D. Tutor: Pospisilova M., Dept. of Analytical Chemistry, Faculty of Pharmacy in Hradec Kralove, Charles University in Prague A new method of micellar elektrokinetic chromatography (MEKC) with UV detection at 190 nm and 265 nm for the determination of paracetamol (PA), ascorbic acid (AA) and phenylephrine (FE) in pharmaceutical preparations was devised and optimised. The analysis was carried out in a fused-silica capillary (internal diameter 50 m, total length31,2 cm and effective length 21 cm), with voltage 20 kV, temperature 20 o C and sample injection for 5 seconds under the pressure of 34,5 mbar. Optimum background electrolyte (BGE) was 5 mM sodium tetraborate and 5 mM potassium dihydrogen phosphate containing 150 mM sodium dodecyl sulphate (SDS) as a surfactant and 10 % (v/v) of methanol. pH* 8,2 was found to be optimal. Methylparaben (MP) was used as internal standard. The peaks of the drugs were satisfactorily separated from the peak of internal standard as well as from the EOF. The separation took less than 9 minutes and the overall analysis time involving appropriate rinsing of the capillary was less than 15 minutes. The calibration curves were...
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Determination of Nefopam by the Technique of Sequential Injection Analysis with Chemiluminescence Detection
Štěpánková, Lucie ; Pospíšilová, Marie (referee) ; Polášek, Miroslav (advisor)
1.1 Abstrakt A simple and rapid automated method for the assay of nefopam hydrochloride by sequential injection analysis (SIA) with chemiluminescence detection was devised and optimised. The optimised parameters were aspirated volumes of the nefopam hydrochloride sample and reagents, flow rate, composition of the carrier stream, the photomultiplier voltage and the influence of materials used in the production of tablets. Optimum sample volume was 60 μl and the optimum reagent concentrations (and aspirated volumes) were - 10 mM Ce(IV) ammonium sulphate in 50 mM sulphuric acid (40 μl), 3 mM tris(2,2'-bipyridyl)dichlororuthenium(II)hexahydrate in 50 mM sulphuric acid (59 μl) and 7 mM sodium acetate (34 μl). The optimum flow rate in the system was 64 μl/s and that for transporting the luminescent zone to the detector was 78 μl/s. The photomultiplier voltage was 280 V. The carrier stream was ultrapure water. The calibration curve was rectilinear in the range 5.10-7 - 1.10-5 µmol/l of nefopam hydrochloride. The parameters of the calibration curve y = kx + q (where y is the intensity of chemiluminescence in nA and x stands for the concentration of nefopam hydrochloride in µmol/l) were calculated by the linear regression method. The slope k was 22.398 and the intercept q was 0.7161. The correlation coefficient was...
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