Immobilization of proteins on metal ion chelated polymer surfaces

Over the last decade, the chelator-based strategy for protein immobilization has received considerable attention. Here, we describe a stepwise approach for the modification of polyurethane (PU) surfaces which involves the introduction of a poly(ethylene glycol) (PEG) layer to shield the PU substrate surface against nonspecific protein adsorption and a chelator head (quinolin-8-ol, HQ), to provide relatively high-target protein binding capacity. The surface properties, the immobilization of proteins on the surface, and the bioactivity of the immobilized proteins were investigated by various techniques. It was demonstrated that this approach provides a powerful means for surface immobilization of proteins with high density, with a homogeneous distribution and retaining the bioactivity of the immobilized proteins.