Dendrimer modified silica gel for anion exchange chromatography: synthesis, characterization and application

The novel grafted silica supports were investigated. The anion exchanger was prepared by chemical modification of a bare silica gel surface. The support was coated with a polymeric moiety formed by condensation polymerization of primary amine with diepoxide. The synthesized copolymer of methylamine (MA) and 1,4-butanedioldiglycidyl ether (BDDE) exhibited a dendrimer structure. The prepared materials were characterized by elemental analysis, FT-IR spectroscopy and solid state (13)C and (29)Si NMR CP-MAS spectroscopy. The porous structure of the adsorbents was investigated using the low temperature nitrogen adsorption (LTNA) method. It allows determination of the influence of the topology of packing materials on their chromatographic properties. Imaging was also carried out on the surfaces of the synthesized materials by scanning electron microscopy (SEM). The obtained stationary phase was applied in ion chromatography for the separation of inorganic anions (F(-), Cl(-), NO(2)(-), Br(-), NO(3)(-), HPO(4)(2-), SO(4)(2-), ClO(4)(-)). Bicarbonate buffer was used as a mobile phase.