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Comparison of detection cells for chemiluminescent determination of cobalt ions
Dospělová, Veronika ; Hraníček, Jakub (advisor) ; Nováková, Eliška (referee)
In this thesis, a method for the determination of cobalt ions by sequential injection analysis was developed and optimized. The chemiluminescent reaction of luminol was used for the determination of cobalt ions, where its oxidation by hydrogen peroxide is catalysed by cobalt ions in a basic medium. The reaction is accompanied by the emission of radiation in the form of chemiluminescence, which is detected at a peak wavelength of 425 nm. The determination was carried out in several experimental setups with different types of detection cells. For each setup, the measurement conditions were optimized to achieve the highest and at the same time stable signal of the chemiluminescent radiation intensity. Subsequently, under the optimized conditions, the individual calibration dependencies were measured, and the basic measurement characteristics were determined. Based on these characteristics, the most suitable layout and type of detection cell were selected for which interference studies of selected major cations were measured. The developed method was applied to the determination of vitamin B12 samples. The vitamin molecule contains just one cobalt atom, which was released by different types of decomposition prior to determination. Keywords Sequential injection analysis Chemiluminescence Luminol Cobalt...
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Determination of Procaine by Flow Injection and Sequential Injection Analysis with Spectrophotometric Determination
Tomanová, Marie ; Hraníček, Jakub (advisor) ; Rychlovský, Petr (referee)
This diploma thesis is focused to the determination of procaine using flow injection and sequential injection analysis coupled with spectrophotometric detection. This determination is based on the reaction of procaine with a colouring agent, 1,2-naphthoquinone-4-sulfonic acid. An orange coloured product is formed, which is determined spectrophotometrically at the wavelength 484 nm. The high of the absorption signal of the product is directly proportional to the concentration of procaine. The aim of this work was to optimize the parameters of both methods of flow analysis so that the limit concentration of procaine can be as low as possible and at the same time, high sensibility is achieved. The next step was to apply these methods on the determination of procaine in real samples. It was found that in flow injection analysis, the absorbance of procaine hydrochloride obeys Beer's law for concentrations from 2.5 to 120 µg/ml. The linear regression equation of calibration graph was y = 0.0059x - 0.0051, with a linear regression correlation coefficient 0.9993. Limit of detection was 0.72 µg/ml. Effects of standing time (stopped-flow), flow rate, concentration of colouring agent, pH and the volume of the sample loop have been examined and optimized. It was also found that in sequential injection...
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Determination of Heparin by Sequential Injectin Analysis with Spectrophotometric Detection
Lišková, Růžena ; Hraníček, Jakub (advisor) ; Nesměrák, Karel (referee)
In this work the determination of heparin using Sequential Injection Analysis (SIA) technique with spectrophotometric detection was studied. The principle of this method was measuring the decrease of absorbance of phenothiazine dyes in its maximum wavelength caused by its interaction with heparin. The decrease is proportional to concentration of heparin in sample. The aim of this work was to find optimum conditions for determination of heparin by the SIA with spectrophotometric detection and to try to apply this measurement to real sample under these conditions. Three phenothiazine dyes were used: Methylene Blue, Azure A and Azure B and for each of them an optimum concentration was found. Their values were for methylene blue 4.0 ∙ 10-5 mol/dm3 and 5.0 ∙ 10-5 mol/dm3 for Azure A and Azure B. 150 µl was chosen as an optimum amount of heparin and reagent aspirated. Optimum reaction time was 0 s and flow rate during measurement 1.5 ml/min. Working concentration range was found between 0.23 and 15 mg/dm3 for methylene blue, 1.2 and 13 mg/dm3 for Azure A and 0.67 and 12 mg/dm3 for Azure B. Limit of detection varied between 0.09 - 0.35 mg/dm3 and limit of quantification between 0.30 and 1.2 mg/dm3 for different dyes. Relative standard deviation was determined as a measure of repeatability. Its values were...
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Chemiluminescent determination of vitamin B12 using sequential injection analysis
Doležalová, Veronika ; Hraníček, Jakub (advisor) ; Dian, Juraj (referee)
This bachelor thesis deals to find the optimal conditions for the determination of vitamin B12 by the Sequential Injection Analysis (SIA). The basis of the determination is a chemiluminescence reaction in which luminol is oxidized by hydrogen peroxide under the catalysis of cobalt ions in a basic medium. The intensity of the chemiluminescence radiation was measured using a spectrofluorometric detector and the measured intensities were recorded. Suitable experimental conditions were found experimentally before the actual determination. A total of 4 parameters were optimized, namely, the mass percentage of hydrogen peroxide, the ratio between the dosed cobalt ion sample and the luminol solution, the sample flow rate and the luminol concentration. Under optimized conditions, several solutions of known cobalt ion concentration were measured, from which a calibration dependence of chemiluminescence intensity on cobalt ion concentration could be established. For this determination, the basic characteristics were determined. For the determination of vitamin B12 itself by the SIA technique, it was assumed that the vitamin molecule contains exactly one cobalt atom, which was released from the molecule by the action of UV radiation. At the end of the work, the concentration obtained by the measurement was...
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Determination of Nadroparine in Fraxiparine injection solution using flow techniques of anlysis
Miklošinová, Aneta ; Hraníček, Jakub (advisor) ; Křížek, Tomáš (referee)
This thesis was focused on a determination of nadroparin using sequential injection analysis and flow injection analysis with fluorimetric and spectrophotometric detection. The principle of determination was based on the interaction of nadroparin with phenothiazine dye. Methylene blue was used as phenothiazine dye. The determination was performed on a laboratory made FIA instrument and on the commercial SIA instrument. Optimal conditions for SIA were concentration of dye 6 ∙ 10-5 mol dm-3 , injected volume 100 µl, flowrate 1,5 ml min-1 , for FIA: concentration of dye 3 ∙10-5 mol dm-3 flowrate 2 ml ∙ min-1 , injected volume= 100 µl, for fluorimetric detection was sensivity of the detector 1000 V, Emission was measured by 2 nm and excitation wavelenght 621 nm. For spectrophotometric detection, absorbance was detected at the absorption maximum wavelength. Repeatability ranged from 2.01 to 2.85%. The limit of detection for FIA was 0.05-0.09 IU ml-1 , for SIA were limits of detection in range 0,25 - 1,63 IU ml-1 , limits of quantification in range 0,83 - 5,44 and linear range was from 0,5 - 20 IU ml-1 . The limits of detection, limits of determination and the linear range could be corrected for the SIA by the injected volume of phenothiazine dye.
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Determination of Heparin by Sequential Injectin Analysis with Spectrophotometric Detection
Lišková, Růžena ; Hraníček, Jakub (advisor) ; Nesměrák, Karel (referee)
In this work the determination of heparin using Sequential Injection Analysis (SIA) technique with spectrophotometric detection was studied. The principle of this method was measuring the decrease of absorbance of phenothiazine dyes in its maximum wavelength caused by its interaction with heparin. The decrease is proportional to concentration of heparin in sample. The aim of this work was to find optimum conditions for determination of heparin by the SIA with spectrophotometric detection and to try to apply this measurement to real sample under these conditions. Three phenothiazine dyes were used: Methylene Blue, Azure A and Azure B and for each of them an optimum concentration was found. Their values were for methylene blue 4.0 ∙ 10-5 mol/dm3 and 5.0 ∙ 10-5 mol/dm3 for Azure A and Azure B. 150 µl was chosen as an optimum amount of heparin and reagent aspirated. Optimum reaction time was 0 s and flow rate during measurement 1.5 ml/min. Working concentration range was found between 0.23 and 15 mg/dm3 for methylene blue, 1.2 and 13 mg/dm3 for Azure A and 0.67 and 12 mg/dm3 for Azure B. Limit of detection varied between 0.09 - 0.35 mg/dm3 and limit of quantification between 0.30 and 1.2 mg/dm3 for different dyes. Relative standard deviation was determined as a measure of repeatability. Its values were...
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Determination of Procaine by Flow Injection and Sequential Injection Analysis with Spectrophotometric Determination
Tomanová, Marie ; Hraníček, Jakub (advisor) ; Rychlovský, Petr (referee)
This diploma thesis is focused to the determination of procaine using flow injection and sequential injection analysis coupled with spectrophotometric detection. This determination is based on the reaction of procaine with a colouring agent, 1,2-naphthoquinone-4-sulfonic acid. An orange coloured product is formed, which is determined spectrophotometrically at the wavelength 484 nm. The high of the absorption signal of the product is directly proportional to the concentration of procaine. The aim of this work was to optimize the parameters of both methods of flow analysis so that the limit concentration of procaine can be as low as possible and at the same time, high sensibility is achieved. The next step was to apply these methods on the determination of procaine in real samples. It was found that in flow injection analysis, the absorbance of procaine hydrochloride obeys Beer's law for concentrations from 2.5 to 120 µg/ml. The linear regression equation of calibration graph was y = 0.0059x - 0.0051, with a linear regression correlation coefficient 0.9993. Limit of detection was 0.72 µg/ml. Effects of standing time (stopped-flow), flow rate, concentration of colouring agent, pH and the volume of the sample loop have been examined and optimized. It was also found that in sequential injection...
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Spectrophotometric Determination of Chondroitine Sulphate by Sequential Injection Analysis
Hrubá, Lucie ; Hraníček, Jakub (advisor) ; Kozlík, Petr (referee)
This thesis deals with the optimization determination of chondroitin sulfate sequential injection analysis with spectrophotometric detection. The reaction proceeds in the presence of phenothiazine cationic dyes (Azure A, Azure B and methylene blue) and measuring the decrease absorbance dyes in their absorption maximum after the addition of chondroitin sulfate. Have found the optimum conditions for this determination: dye concentration 5 10-5 mole dm-3 , the dosing volume 100 µl CS + 50 µl dye + 100 µl CS, reaction time 0 s, flow rate 40 µl s-1 . For the determination of the CS in a static arrangement was found the lowest limit of detection and quantification using metylene blue (LOD = 0,23 mg l-1 a LOQ = 0,76 mg l- 1 ). The best repeatibility was achieved also using methylene blue 2,4 %. On the other side the best sensitivity was achieved using azure A. For the determination of the CS in SIA arrangement was found the lowest limit of detection and quantification using azure (LOD = 0,34 mg l-1 a LOQ =1,01 mg l-1 ). The best repeatibility was achieved also using azure A 1,9 %. And the best sensitivity was achieved using azure B. Based on these findings was chondroitin sulphate determined in food supplements, the more suitable method were the calibration curve .The determination was also carried out...
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