The separation of pancreatic trypsinogen and alpha -chymochypsinogen A by d
isplacement chromatography was tested on a bifunctional adsorbent containin
g both butyl and carboxymethyl groups. Methacrylic triblock copolymer was s
ynthesized and used as the displacer. Compared to the displacement results
on commercial Butyl-Sepharose, it was found that both the separation and re
covery of trypsinogen and alpha -chymochypsinogen A were improved. Adsorpti
on isotherms of proteins were measured on both the commercial Butyl-Sepharo
se and the synthesized bifunctional adsorbents. It was found that the impro
vement of protein separation on bifunctional adsorbents was attributed to t
he alteration of the adsorption of trypsinogen. Charge repulsion between tr
ypsinogen and the negatively charged carboxymethyl groups may account for t
he alteration. In addition, taking advantage of the effect of charge repuls
ion, the column regeneration became much easier on the column packed with b
ifunctional adsorbents.