Influence of brush length of PVP chains immobilized on silicon wafers on their blood compatibility

In this study, the influence of variations in chain length of polyvinylpyrrolidone (PVP) brushes on the blood compatibility of silicon wafer surfaces to which they were chemically attached was studied. Si surfaces were functionalized with various lengths of PVP brush using atom transfer radical polymerization technology and confirmed by elliptical polarized light, atom force microscopy, and X-ray photoelectron spectroscopy. The blood compatibility of these biointerfaces were systematically investigated by measuring protein adsorption, clotting time, platelet adhesion, contact activation, and complement activation. The results indicate that the hemocompatibility of the surfaces was highly related to PVP brush chain length and hydrophilicity of the surfaces. Our results contribute to rational biointerface design for specific biomedical applications. The results reveal that the PVP brushes with a long chain length have great potential for blood contacting applications due to their reduced protein absorption and cell activation following its contact with blood.