Incorporation of Lysine-Containing Copolymer with Polyurethane Affording Biomaterial with Specific Adsorption of Plasminogen

A novel biomaterial based on polyurethane (PU) was prepared through physical incorporation of lysine-containing copolymer to improve its hemocompatibility and surface recognition of plasminogen. The lysine-containing copolymer was synthesized via the copolymerization of 2-ethylhexyl methacrylate (EHMA), oligo (ethylene glycol) methyl ether methacrylate (OEGMA) and 6- tert -butoxycarbonyl amino-2-(2-methyl-acryloylamino)-hexanoic acid tert -butyl ester (Lys(P)MA), followed by the deprotection of COOH and ε -NH 2 groups on lysine residues in the copolymer. The composition of the copolymer can be adjusted by varying the monomer feed ratio. The three components contribute to improving the compatibility with PU, resistance to nonspecific protein adsorption and specific binding of plasminogen, respectively. The binding capacity towards plasminogen increased with the lysine content in the copolymer. This approach illustrates a simple way for the generation of novel biomaterials with improved hemocompatibility and surface recognition of specific biomolecules.