Dye–ligand affinity electrochromatography with transverse and/or longitudinal electric field

A novel preparative electrochromatographic column with seven compartments was developed. The design gave promise to provide transverse, longitudinal or two-dimensional (2D) electric field on the column. The central gel compartment of 2 mL was packed with dye–ligand affinity adsorbent. Bovine serum albumin (BSA) was used as a model protein to investigate the dynamic adsorption behavior in the electrochromatography. The effects of various operating variables indicated that the electroosmotic flow on the charged adsorbent surface could promote the intraparticle mass transport of the protein, leading to the increase of its dynamic binding capacity (DBC). Moreover, it was confirmed that the 2D electric field promoted the mass transport more efficiently than a 1D electric filed. Hence, the DBC of BSA was 4.5 times increased with the 2D electric filed as compared to the 2.4 times increase in a 1D electric field. The results have proven that the 2D electrochromatography is promising for high capacity protein adsorption.