Polymer displacement in dye-affinity chromatography

Displacement of lactate dehydrogenase from dye-affinity matrices with poly(ethyleneimine) (PEI) was shown to be an effective elution strategy. It resulted in better recoveries and sharper elution profiles than traditional non-specific elution while the purification factors were unchanged. The elution is assumed to proceed via displacement of bound protein by PEI when the polymer binds to the dye-ligands. Complete elution of bound protein is a characteristic feature of such a mechanism. Hence displacement with PEI may be a promising strategy for eluting proteins with reported low recoveries in dye-affinity chromatography protocols.