Binding of β-amyloid to sulfated sugar residues in a polymer brush.

A glycopolymer obtained by living radical polymerization of glucose-carrying vinyl monomer was sulfated and accumulated as a polymer brush on a gold colloid-immobilized glass. Binding processes of various proteins to sulfated glucose residues in the brush were examined by the increase in absorbance with a help of localized surface plasmon resonance. β-Amyloid protein (Aβ) bound to the sulfated glycopolymer brush, whereas no binding to the non-sulfated one. An AFM image of Aβ aggregates on the sulfated brush was ellipsoidal, whereas no-shaped aggregation of Aβ on the poly(methacrylic acid) and poly[2-(dimethylamino)ethyl methacrylate] brushes. The present results indicate the importance of balance between electrostatic attraction and repulsion in the folding-aggregation phenomena of Aβ at the surface of glycopolymers.