title: Adamantyl-group containing mixed-mode acrylamide-based continuous beds for capillary electrochromatography. Part II. Characterization of the synthesized monoliths by inverse size exclusion chromatography and scanning electron microscopy.
abstract: In our previous article we have described the synthesis of a new amphiphilic monolithic stationary phase by in situ free radical copolymerization of cyclodextrin-solubilized N-adamantyl acrylamide, piperazinediacrylamide, methacrylamide and vinylsulfonic acid in aqueous medium in pre-treated fused silica capillaries of 100μm I.D. In the present work, we study the morphology of different monolithic stationary phases synthesized under variation of the concentration of ammonium sulfate in the polymerization mixture. The pore size distribution is determined with inverse size exclusion chromatography (ISEC) using the retention data of a series of polystyrene standards with narrow molecular size distribution and known average molar mass ranging from 1560 to 2010000gmol(-1). The impact of the concentration of the lyotropic salt ammonium sulfate in the polymerization mixture on the formed morphology, the pore size distribution, and the fractional volume of mesopores and macropores is determined. The homogeneity and uniformity of the formed monolith over the length of the capillary and the covalent attachment to the confining walls are confirmed. Repetition of the synthesis procedure shows that these morphology parameters are well controlled as there is an excellent capillary-to-capillary, day-to-day, and run-to-run reproducibility reached for the electroosmotic mobility and the retention factor determined with alkylphenones in the reversed-phase mode.
authors.affiliation: University of Marburg, Department of Chemistry, Hans-Meerwein-Straße, D-35032 Marburg, Germany.
authors.lastname: Ayat Allah Al-Massaedh
authors.affiliation: University of Marburg, Department of Chemistry, Hans-Meerwein-Straße, D-35032 Marburg, Germany. Electronic address: pyellu@staff.uni-marburg.de.
authors.forename: Ute
authors.initials: U
authors.lastname: Pyell
mesh_terms: D020106:Acrylamide / Q000737:chemistry*; D002138:Calibration; D053801:Capillary Electrochromatography / Q000379:methods*; D002850:Chromatography, Gel / Q000379:methods*; D008855:Microscopy, Electron, Scanning / Q000379:methods*; D016062:Porosity; D015203:Reproducibility of Results
chemical_list: D020106:Acrylamide
keywords: Acrylamide-based continuous beds; Inverse size exclusion chromatography; Monolithic stationary phase; Morphology; Pore size distribution; Scanning electron microscopy