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The assesment of chloramphenicol residues in biological material, water and feed by GC/MS
Lukačková, Dagmar ; Šalplachta, Jan (referee) ; Rejtharová, Martina (advisor)
This diploma thesis addresses the presence and determination of chloramphenicol residues in biological materials. The theoretical part presents the literature retrieval containing information about veterinary medicaments with the banned use in food producing animals and also the sum of the legislative requirements concerning the presence of these substances in foodproducts and raw food materials of animal origin. The comparison was carried out between the existing analytical methods used for the determination of chloramphenicol residues in different biological materials, which are altogether based on the solid phase extraction for the extract cleaning and the new procedures for sample preparations using columns where the sorbent performs on the molecularly imprinted polymers principle.
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Development of methods for the voltammetric determination of chloramphenicol and dinitramin at amalgam electrodes
Štafurová, Kristína ; Fischer, Jan (advisor) ; Vyskočil, Vlastimil (referee)
The first part of this diploma thesis deals with the determination of chloramphenicol (CLF) on the retractable-pen-based renewable silver amalgam film electrode (RAE) by differential pulse voltammetry (DPV). Calibration dependencies in the concentration range of 10-100 µmol dm−3 and 1-10 µmol dm−3 were obtained. Repeated RAE surface restoration when determining CLF does not contribute to the repeatability of the signal. The determination limit was 2,2 µmol dm−3 . In the second part of the work, the conditions for the determination of dinitramine (DN) were examined on the meniscus-modified silver solid amalgam electrode by DPV technique. The Britton-Robinson buffer pH 5 was chosen as the optimal medium. In this electrolyte, the impact of regeneration potentials on DN signal stability was monitored. Regeneration pulses or methanol rinses did not contribute to the stability of the signal. There is a strong passivation on the electrode, so this type of electrode is not suitable for determination of this analyte. The possible solution is to use RAE, in which mechanical surface restoration is an effective way of solving the passivation on the electrode surface. In the third part of the work, dinitramine was studied at the RAE. The best repeatability of the measurements was achieved by activation of the...
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Development of method for voltammetric determination of chloramphenicol at retractable-pen-based renewable silver amalgam film electrode
Štafurová, Kristína ; Fischer, Jan (advisor) ; Dejmková, Hana (referee)
This diploma thesis is focused on the determination of chloramphenicol (CLF) by differential pulse voltammetry (DPV) on retractable-pen-based renewable silver amalgam film electrode (RAE). For the determination of chloramphenicol the optimum conditions were found. Under these conditions concentration dependences were measured and then limits of quantification were calculated. The effect of pH of Britton- Robinson buffer was tested and the stability of the signal with repeated measurements was monitored. For determination of CLF by DPV BR buffer pH 7 was chosen as an optimum background electrolyte. Under these conditions linear dependences were obtained in the concentration range of 1·10−5 −1·10−4 mol·dm−3 and 1·10−4 −8·10−4 mol·dm−3 . The limit of determination for CLF by DPV at 1,4·10−5 mol·dm−3 was found.
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Voltammetric Determination of Chloramphenicol and Chlorambucil on Amalgam Electrodes
Havlíková, Štěpánka ; Fischer, Jan (advisor) ; Zima, Jiří (referee)
This diploma thesis is focused on the determination of chloramphenicol by differential pulse voltammetry (DPV), DC voltammetry (DCV), cyclic voltammetry (CV) and adsorptive stripping voltammetry (AdSV) on a meniscus modified silver solid amalgame electrode (m- AgSAE). For the determination of chloramphenicol the optimum conditions were found and under these conditions concentration dependences were measured and then limits of quantification were determined. The influence of pH of BR buffer was tested. For determination of chloramphenicol by DCV pH 7 was chosen as an optimum background and pH 8 was chosen as an optimmum for DPV determination. Under these conditions linear dependences were obtained in the concentration range of 1·10-6 - 1·10-4 mol·l-1 . The limit of detection of chloramphenicol by DCV was 2.3·10-6 mol·l-1 . The limit of detection of chloramphenicol by DPV was 2.1·10-6 mol·l-1 in distilled water, 2.9·10-6 mol·l-1 in river water and 4.2·10-6 mol·l-1 in drinking water. Electrochemical behavior of chloramphenicol was studied by cyclic voltammetry in BR buffer with pH 2, 6, 8, 12 and then mechanism of reduction of chloramphenicol was propose based on available literature. Chloramphenicol was determined in drug Spersadex by DPV in BR buffer with pH 8. The optimal conditions for determining...
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The assesment of chloramphenicol residues in biological material, water and feed by GC/MS
Lukačková, Dagmar ; Šalplachta, Jan (referee) ; Rejtharová, Martina (advisor)
This diploma thesis addresses the presence and determination of chloramphenicol residues in biological materials. The theoretical part presents the literature retrieval containing information about veterinary medicaments with the banned use in food producing animals and also the sum of the legislative requirements concerning the presence of these substances in foodproducts and raw food materials of animal origin. The comparison was carried out between the existing analytical methods used for the determination of chloramphenicol residues in different biological materials, which are altogether based on the solid phase extraction for the extract cleaning and the new procedures for sample preparations using columns where the sorbent performs on the molecularly imprinted polymers principle.
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