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Optimisation of HPLC clotrimazole determination
Žáková, Petra ; Sklenářová, Hana (advisor) ; Matysová, Ludmila (referee)
High-performance liquid chromatographic technique for the determination of clotrimazole and its degradation products (2-chlorophenyl)-diphenyl methanol and imidazole in the formulation Clotrimazol spray 1 % was developed. The presented thesis was focused to the selection of optimal column, composition of mobile phase, its pH and internal standard for the analysis of pharmaceutical formulation based on topically applied antifungal agent clotrimazole. Seven columns were tested in detail. The tested columns were: Discovery HS F5 (5 μm, 150 x 4.6 mm)Chromolith® Performance, RP-18e (100 x 3 mm)ZIC® HILIC (3.5 μm, 50 x 2.1 mm)XTerra® RP 18 (5 μm, 100 x 3 mm)Discovery RP Amide C 16 (5 μm, 250 x 3 mm)Zorbax Extend-C18 (3.5 μm, 75 x 4.6 mm)Discovery ZR-PBD (5 μm, 150 x 4.6 mm). HPLC was carried out using Discovery ZR- PBD column 5 μm, 150 x 4.6 mm. This column is based on polybutadiene-coated zirconium oxide. A zirconium oxide is stable in the whole pH range with the high pressure and temperature up to 200řC. Spectrophotometric detection at 210 nm was performed. The optimal mobile phase was a mixture of acetonitrile and water (pH 9.7) in the ratio of 50:50. The pH of the water component was finally adjusted to 9.7 with NH4OH 25 %. The aqueous solution was filtered through 0.45 m Millipore...
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Effect of flow rate on the kinetic and the possibility of evaluating different reactions in the SIA system
Mrákotová, Vladěna ; Sklenářová, Hana (advisor) ; Šatínský, Dalibor (referee)
2 ABSTRACT Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of analytical chemistry Candidate: Vladěna Mrákotová Supervisor: Doc. PharmDr. Hana Sklenářová, Ph.D. Title of diploma thesis: Effect of flow rate on the kinetic and the possibility of evaluating different reactions in the SIA system The diploma thesis dealt with testing the effect of mixing and flow rate on the kinetic and the possibility of evaluating different reactions in the SIA system with spectrophotometric detection. Absorbance was measured for two kinds of chemical reactions with different reaction speed. For faster running reaction color change of bromothymol blue (BTB) with sodium hydroxide (NaOH) by the change in pH was evaluated by the increase in absorbance of blue form/decrease in absorbance of yellow form of BTB. The effect of flow rate and method of mixing (different sequence aspirations, different mixing ratio of working solution) was tested. The same parameters were also tested for slowly running two-step reaction of nitrites (D) with a diazo-coupling reagent (DKC). Furthermore, stop-flow technique was applied to see the effect of stopping the flow at certain parts of the flow system. The "sandwich" technique was tested too. The obtained results were evaluated using peak heights and peak areas. In...
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Testing optical properties of Quantum-Dots nanoparticles I.
Klusoňová, Edita ; Sklenářová, Hana (advisor) ; Polášek, Miroslav (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Edita Klusoňová Supervisor: Doc. PharmDr. Hana Sklenářová, Ph.D. Title of diploma thesis: Testing optical properties of Quantum-Dots nanoparticles I. The diploma thesis deals with testing optical properties of Quantum-Dots nanoparticles (QDs), which have been verified as chemiluminescence (CL) signals enhancers. For the reaction luminol (5-aminophthalhydrazide) was used in alkaline medium, which was oxidized by hydrogen peroxide in the presence of catalyst potassium ferricyanide. The experiment was performed in the sequential injection analysis (SIA) system using detection in spiral flow cell Schoeffel. Different concentration levels of QDs nanoparticles were tested with main focus on low concentrations. QDs solutions with different emission maxima and surface modification were tested, which were prepared at the Department of bioanalytical instrumentation in the Institute of Analytical Chemistry in Brno. The following modifications of CdTe nanoparticles were used: mercaptopropionic acid (MPA 520 nm, MPA 540 nm, MPA 636 nm), thioglycolic acid (TGA 620 nm), mercaptoethylamine (NH2 590 nm) and CdTe/CdS particles coated with mercaptopropionic acid (MPA CdTe/CdS 640 nm). Every particle was...
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Automation of liberation tests for releasing biologically active substances from nanofibers
Kodedová, Marie ; Sklenářová, Hana (advisor) ; Chocholouš, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of analytical chemistry Candidate: Marie Schneidrová Supervisor: doc. PharmDr. Hana Sklenářová, Ph.D. Title of the diploma thesis: Automation of liberation tests for releasing biologically active substance from nanofibers The main goal of this diploma thesis is an automation of TTC liberation from nanofibers, using non-separation flow method sequential injection analysis. UV-VIS spectrophotometer was used for the detection of signal. Measurements were carried out using 1-3 connected Franz cells in parallel, palced in the water bath. Buffer solutions with pH 7.4 and 4.5 were used as liberation media. The liberation of TTC was realized from two different nanofiber carriers - types "A" and "AK", Difference was in their preparation process. Because of this, each of them revealed various characteristics mainly related to the amount of bound TTC and the way of its binding to the nanofiber carrier. Production of these nanofibers was realized by Technical University Liberec using the technology NanoSpiderTM . Measurements were performed under various predetermined conditions, representing the state of the human skin - two different pH (7.4; 4.5) and temperature (32řC; 37řC) values. Four different types of membrane filters were also used,...
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Development of supercritical fluid extraction for isolation of biologically active substances
Kuda, Lukáš ; Pilařová, Veronika (advisor) ; Sklenářová, Hana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Lukáš Kuda Supervisor: PharmDr. Veronika Pilařová, Ph.D. Title of Diploma Thesis: Development of Supercritical Fluid Extraction for Isolation of Biologically Active Substances The main aim of this study was to optimize the method for extraction of quercetin - flavonoid with antioxidant activity - from dried crushed quince fruit (Cydonia oblonga Mill.) using supercritical fluid extraction (SFE). The supercritical fluid extraction is a method in which supercritical fluid is used to extract active compounds. Neat CO2 is the most common used solvent. Due to its physicochemical properties, it is suitable solvent for the extraction of non-polar compounds. While extraction of polar compounds id required, the organic solvents such as ethanol, methanol or isopropanol are added to the supercritical fluid. Depending on the amount of added organic solvent, SFE, SFE with modifier, CO2 expanded liquid extraction and pressurized liquid extraction are distinguished. Temperature and pressure are other key parameters affecting extraction and need to be optimized as well. The optimization of the quercetin extraction method was carried out in several following steps. First, the key parameters were tested using...
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Development of on-line solid phase extraction using flow methods
Vinklárek, Jan ; Chocholouš, Petr (advisor) ; Sklenářová, Hana (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical chemistry Candidate: Bc. Jan Vinklárek Supervisor: doc. PharmDr. Petr Chocholouš, Ph.D. Title of the diploma thesis: Development of on-line solid phase extraction using flow methods The goal of this diploma thesis was to create and validate method using combination of SPE extraction and flow methods (in this case method SIA). Creatinine was chosen as extracted analyte and urine was chosen as biological material. At first, the method was optimized (concentration and flow rate of wash reagent and flow rate of sample and standards). Then the limits of the created method were tested. Finally, the trueness and repeatability of results was tested and also stability of diluted samples. All of these tests (in thesis named experiments) had good results. Final parameters of method are: Sorbent - SPH Iontosorb 100 Wash reagent - 50% acetonitrile, aspirated 0,5 ml Elute reagent - 1% water solution of ammonia hydroxide, aspirated 0,5 ml Sample diluted by acetic acid with pH 2,4, aspirated 20 µl, or 10 µl according to sample concentration (method alone makes decision about changing aspirated volume, decision algorithm is in the program) Method of standard adding is used for measuring creatinine concentration in...
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Analysis of nutritionally important substances in fruit tree waste products by HPLC
Šírová, Karolína ; Šatínský, Dalibor (advisor) ; Sklenářová, Hana (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Bc. Karolína Šírová Supervisor: doc. RNDr. Dalibor Šatínský, Ph.D. Consultant: Mgr. Anežka Adamcová Title of Diploma Thesis: Analysis of nutritionally important substances in fruit tree waste products by HPLC This diploma thesis deals with the content of phenolic compounds in various parts of tree of the genus Pyrus. The theoretical part is focused on characterization, biosynthesis, chemical and biological properties of major phenolic compounds in pear-trees and the possibilities of their determination with the use of the latest scientific studies. The experimental part contains an extensive analysis of arbutin, chlorogenic acid, 1,5- dicaffeoylquinic acid, 3,5- dicaffeoylquinic acid and rutin in extracts of leaves, bark, buds, fruits, flowers and wood chip. Developed and validated HPLC-DAD method was used and the total antioxidant activity was determined by FIA method with electrochemical detection. An ASCENTIS Express RP-Amide 150×4.6 mm, 2.7 μm analytical column and gradient elution consisting of organic part of acetonitrile (ACN) and water part with 0,85% phosphoric acid (pH = 2.2) were used for analysis. The detection was performed by DAD detector at wavelengths 220 nm, 327 nm and 354 nm. The...
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Monitoring the profile of phenolic substances in different parts of apple trees by HPLC
Šilhavá, Kristýna ; Šatínský, Dalibor (advisor) ; Sklenářová, Hana (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Bc. Kristýna Šilhavá Supervisor: doc. RNDr. Dalibor Šatínský, Ph.D. Consultant: Mgr. Anežka Adamcová Title of Diploma Thesis: Monitoring the profile of phenolic substances in different parts of apple trees by HPLC This diploma thesis covers the performance of a quantitative analysis of phenolic compounds in ten different cultivars in Malus. Specifically, the presence of phloridzin, phloretin, rutin, quercitrin and chlorogenic acid was monitored. Extracts of buds, flowers, leaves and bark in each species were analyzed during the four different vegetation periods. Further, the presence of phenolic compounds in samples of wood chips and fruits was monitored. The determined analytes displayed a different content profile depending on the plant material, apple cultivar and the period in which they were collected. Except for fruits, phloridzin was the dominant component in all varieties and in all materials. The highest total concentration of phenolic compounds was found in the leaves in the spring March-April 2020 in species 'Rubinstep'. This diploma thesis used a developed and validated HPLC-DAD method for a large number of extracts. A YMC-Triart C18 ExRS column (150 × 4.6 mm × 5 µm, 8 nm) was chosen...
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