Separation of biomolecules by μ-high-performance anion-exchange chromatography using a tentacle-like stationary phase

A variety of biomolecules and their variants, which have previously been problematic to separate, have been analysed using a novel anion-exchange resin based on a non-porous polystyrene polymeric support with a hydrophilic coating and grafted tentacular quaternary ammonium functional groups. The hydrophilic coating results in minimal interaction between the support and the biomolecule, while the highly. exible tentacular-like anion- exchange groups increase the ionic interaction potential and act as an umbrella to hold the proteins away from the surface. Because of the removal of silanophilic interactions, minimisation of hydrophobic interactions, and the highly. exible nature of the tentacle-like ion exchangers, ionic interactions can therefore dominate the separation. As such this phase is highly suited to the separation of highly charged biomolecules and their variants. This polymeric strong anionexchange ( SAX) support was packed into a fused-silica capillary column and, using a salt concentration gradient, various recombinant proteins were analysed by mu-HPLC resulting in baseline resolution.