Adsorption of human serum albumin on to synthesized dye-like polystyrene gel beads

In bioseparation, adsorption of proteins on to various polymer surfaces plays an important role in different fields, particularly in pseudo-affinity chromatography techniques. In this context, this study aims to synthesize cross-linking polystyrene gel beads as packing material in column chromatography for albumin purification. Suitable chemical groups, such as sulfonate and l-cysteine with high affinity towards human serum albumin were introduced on the aromatic ring of the hydrophobic adsorbing polystyrene support. These functional groups were chosen on the basis of the interactions of albumin with their exogenous and endogenous ligands in such manner to confer this material a highly binding ability and enhance its efficacy. Adsorption of human albumin on to these two synthesized adsorbents was performed at 37 °C in physiological pH 7.3 during 20 min of incubation. The adsorbed albumin content at interface allows to establish the adsorption isotherm curves. The adsorption rate on both resins was found to be significantly high and the affinity constants, evaluated by the Langmuir model, were: 7.5×105 and 1.45×106 M−1 for poly(styrene sodium sulfonate) and poly(styrene cysteine sulfamide), respectively. Thus, the obtained material gel beads could be used advantageously as a dye-like stationary phase in chromatographic separation of albumin instead of other conventional supports.