Comparison of l-tryptophan binding capacity of BSA captured by a polymer brush with that of BSA adsorbed onto a gel network

A polymer brush containing a diethylamino group as an anion-exchange group was appended onto a polymer substrate by radiation-induced graft polymerization and subsequent chemical modifications. Bovine serum albumin as a chiral ligand for l-tryptophan was bound to the polymer brush at a density ranging from 17 to 150 g BSA/l. For comparison, BSA was adsorbed onto the gel network containing a diethylaminoethyl group. The molar binding ratio of l-tryptophan to BSA on the polymer brush was 1.7-fold higher than that to BSA on the gel network.