Mussel-inspired modification of dextran for protein-resistant coatings of titanium oxide

Surface modification of inorganic materials to prevent non-specific protein adsorption is critically important for developing a biocompatible materials' platform for medical implantation, diagnostics, and therapeutics. Here we report mussel-inspired chemical modification of dextran for anti-fouling coatings of metal oxide. Catechols are conjugated to dextran via a carbamate ester linkage, producing catechol-grafted dextran with a grafting density of 7.3 mol.%. Titanium dioxide (TiO2) is coated with the catechol-grafted dextran, and the anti-fouling effect of dextran coatings is examined by using the adsorption of human serum albumin. The mussel-inspired dextran coatings show excellent resistance to non-specific protein adsorption: the adsorption equilibrium constant (K) is 0.69 L g−1 for dextran-coated TiO2 while that for pristine TiO2 surface is 3.53 L g−1. This study suggests that catechol-grafted dextran is a promising material for effective anti-fouling coatings of implantable inorganic materials.