Polyethylenimine-modified metal oxides for fabrication of packed capillary columns for capillary electrochromatography and capillary liquid chromatography.
The need for novel packing materials in both capillary electrochromatography (CEC) and capillary liquid chromatography (CLC) is apparent and the development towards more selective, application-oriented chromatographic phases is under progress world-wide. In this study we have synthesized new polyethyleneimine (PEI) functionalized Mn(2)O(3), SiO(2), SnO(2), and ZrO(2) particles for the fabrication of packed capillary columns for CEC and CLC. The nanocasting approach was successful for the preparation of functionalized metal oxide materials with a controlled porosity and morphology. PEI functionalization was done using ethyleneimine monomers to create particles which are positively charged in aqueous solution below pH 9. This functionalization allowed the possibility to have both hydrophobic (due to its alkyl chain) and ionic interactions (due to positively charged amino groups) with selected compounds. For comparison aminopropyl-functionalized silica was also synthesized and tested. Both slurry pressure and electrokinetic packing procedures used gave similar results, but fast sedimentation of the material caused some problems during the packing. The high stability and wide pH range of PEI-functionalized SiO(2) material, with potential for hydrophobic and electrostatic interactions, proved to be useful for the CEC and CLC separation of some model acidic and neutral compounds.
Laboratory of Analytical Chemistry, Department of Chemistry, University of Helsinki, Helsinki, Finland.
Susanne K
SK
Wiedmer
Giovanni
G
D'Orazio
Jan-Henrik
JH
Smått
Delphine
D
Bourdin
Clara
C
Baños-Pérez
Motolani
M
Sakeye
Maarit
M
Kivilompolo
Matias
M
Kopperi
José
J
Ruiz-Jiménez
Salvatore
S
Fanali
Marja-Liisa
ML
Riekkola
D001565:Benzoates / Q000737:chemistry; D053801:Capillary Electrochromatography / Q000295:instrumentation*; D002853:Chromatography, Liquid / Q000295:instrumentation*; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D008277:Magnesium Oxide / Q000737:chemistry; D009994:Osmolar Concentration; D010087:Oxides / Q000737:chemistry*; D010316:Particle Size; D011094:Polyethyleneimine / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D017971:Tin Compounds / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry
D001565:Benzoates; D010087:Oxides; D017971:Tin Compounds; D008277:Magnesium Oxide; D012822:Silicon Dioxide; D011094:Polyethyleneimine; D015040:Zirconium; C045358:stannic oxide; C028541:zirconium oxide