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Silica-based monolithic capillary columns modified to zwitterionic stationary phase for hydrophilic interaction liquid chromatography
Moravcová, Dana ; Planeta, Josef ; Kahle, Vladislav ; Horká, Marie ; Roth, Michal
Zwitterionic monolithic capillary columns intended for isocratic gradient hydrophilic interaction chromatography (HILIC) separations are introduced. Silica-based capillary columns (150 mm x 0.1 mm) were prepared by acidic hydrolysis of tetramethoxysilane in the presence of polyethylene glycol and urea. The modification by a 3-(trimethoxysilyl)propyl methacrylate and then by a zwitterionic [2-(methacryloyloxy)ethyl]-dimethyl-(3-sulfopropyl)-ammonium hydroxide to HILIC stationary phase bearing sulfoalkylbetaine groups on its surface followed. Prepared columns were characterized in HILIC separation mode employing mobile phase containing 10% (v/v) of 5 mM ammonium acetate pH = 4.5 in acetonitrile. Comparison with the commercially available ZIC-HILIC® column (Merck SeQuant®) under the same separation conditions using a mixture of aromatic carboxylic acids as a sample was done on the basis of separation efficiency of tested columns as well as retention factors and peak asymmetry of individual solutes.
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Superkritická fluidní chromatografie
Planeta, Josef
Je popsán princip superkritické fluidní chromatografie, současný stav a možnosti instrumentace, spojení s MS nebo MALDI-TOF, uvedeny příklady separací a diskutována možnost použití SFC k získání fyzikálně chemických dat.
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