Ion capacity of siliceous sorbents with surface polymer layers composed of different dextran-triethylenetetraamine mixtures (ion capacity of sorbents with surface polymer layers)

The formation of a polymer layer on the surface of a siliceous support employed for chromatography is one of the methods available for protecting the silica skeleton from dissolution in the mobile alkaline phase and for eliminating the negative influence of silanol groups on separated molecules. A polysaccharide-polyimine copolymer can play the role of the surface layer, especially in siliceous materials, for high performance affinity chromatography. The results presented here demonstrate the utility of the material with such a copolymer layer as a sorbent for metal ions. The ion capacity of sorbents with a copolymer layer composed of triethylenetetraamine-dextran can be changed both by the composition of the mixture and by the amount of crosslinking agent present. The presence of a transition layer on the polymer layer surface explains the distinctions between the ion capacity of sorbents and the concentration of electron-donor nitrogen atoms existing in the material.