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Study of retention properties of polymeric stationary phases
Komůrková, Lenka ; Kučera, Radim (advisor) ; Štěrbová, Petra (referee)
Study of retention properties of polymeric stationary phases Diploma thesis Lenka Komůrková Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Drug Analysis The thesis was focused on the comparison of retention properties of polymer stationary phases based on acrylate and styrene with reversed phases based on zirconium dioxide and commonly used silica gel C18. Cyclosporine A (CsA) and his accompanying impurities B (CsB), C (CsC) and D (CsD) were used model analytes. Measurements were carried out in the analytical scale to obtain basic data for the employment of polymeric phases as the appropriate sorbents in preparative chromatography with regard to their high volume commercial availability. The effect of organic solvent was tested on the separation and separation efficiency. The main attention was focus on the methanolic mobile phases (MF) in the case of polymeric phases due to the economic reasons. All impurities were separated on column silica gel C18 (MF = methanol 80 %) and polymethacrylate C18 (MF = methanol 71 %). Impurity CsB was not separated on column ethylstyrene-divinile copolymers (DVB) (MF = methanol 90 %) and moreover the co-elution of CsD with CsA occured. Peak tailing was observed in a methanolic mobile phase on the...
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Stationary phase based on ionic liquids for separation of ibuprofen impurities
Komůrková, Lenka ; Kučera, Radim (advisor) ; Kastner, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Mgr. Lenka Komůrková Supervisor: Doc. PharmDr. Radim Kučera, Ph.D. Title of diploma thesis: Stationary phase based on ionic liquids for separation of ibuprofen impurities. Rigorous thesis was focused on the determination of ibuprofen and its pharmacopoeial impurities B, E, F and J using gas chromatography coupled with mass spektrometry. The analysis was performer on a SLB-IL 100 capillary column with a stationary phase based on ionic liquid - 1,9-di(3-vinylimidazolium)nonane bis(trifluoromethy) sulfonyl imide. Ibuprofen was derivatized with alkyl chloroformate (isobutyl chloroformate, ethyl chloroformate, heptafluorochloroformate) in the presence of the appropriate alcohol (isobutanol, ethanol, heptafluorobutan-1-ol). The derivatization reaction was successful for all derivatizing agents used. However, the use of ethyl chloroformate appeared to be the best due to the negligible amount of non-derivatized ibuprofen residue. Subsequently, the amount of added alcohol, the derivatization of ibuprofen depending on the retention of the sample in the ultrasonic bath and the influence of the ibuprofen solution on the derivatization and subsequent analysis were investigated....
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Study of retention properties of polymeric stationary phases
Komůrková, Lenka ; Kučera, Radim (advisor) ; Štěrbová, Petra (referee)
Study of retention properties of polymeric stationary phases Diploma thesis Lenka Komůrková Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Drug Analysis The thesis was focused on the comparison of retention properties of polymer stationary phases based on acrylate and styrene with reversed phases based on zirconium dioxide and commonly used silica gel C18. Cyclosporine A (CsA) and his accompanying impurities B (CsB), C (CsC) and D (CsD) were used model analytes. Measurements were carried out in the analytical scale to obtain basic data for the employment of polymeric phases as the appropriate sorbents in preparative chromatography with regard to their high volume commercial availability. The effect of organic solvent was tested on the separation and separation efficiency. The main attention was focus on the methanolic mobile phases (MF) in the case of polymeric phases due to the economic reasons. All impurities were separated on column silica gel C18 (MF = methanol 80 %) and polymethacrylate C18 (MF = methanol 71 %). Impurity CsB was not separated on column ethylstyrene-divinile copolymers (DVB) (MF = methanol 90 %) and moreover the co-elution of CsD with CsA occured. Peak tailing was observed in a methanolic mobile phase on the...
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Assessment of shopping atmosphere in selected stores of retail chains Albert and Billa
Šarlovský, Martin ; Chylíková, Hana (advisor) ; Komůrková, Lenka (referee)
The objective of the thesis is to assess shopping atmosphere of two selected stores Albert and one store Billa and to propose options for improving of any deficiencies. Personal visits and online survey are the chosen methods for the assessment. Thesis is divided into three chapters. The first chapter characterizes shopping atmosphere, shopping environment and business unit. The second chapter describes selected supermarkets Albert and Billa, their organizational structure, ownership and interior and exterior design of selected retail units. The third chapter is practical and assesses the own shopping atmosphere of the stores by using SWOT analysis, pairwise comparison and online survey. Evaluation of the results and proposed possible solutions for improvement of negative points are listed.
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