Surface Zwitterionization of Titanium for a General Bio-Inert Control of Plasma Proteins, Blood Cells, Tissue Cells, and Bacteria

Surface coating of antifouling materials on the substrates offers convenient strategies and great opportunities to improve their biocompatibility and functions of host substrates for wide biomedical applications. In this work, we present a general surface zwitterionization strategy to improve surface biocompatibility and antifouling properties of titanium (Ti) by grafting zwitterionic poly(sulfobetaine methacrylate) (polySBMA). This method also demonstrates its general applicability to graft polySBMA onto Ti surface using different anchoring agents of dopamine and silane. The resulting polySBMA grafted from dopamine- (pTi-D-pSBMA) and silane-anchored titanium surfaces (pTi-Si-pSBMA) surfaces exhibit superlow fouling ability to highly resist the adhesions of plasma proteins, platelets, erythrocytes, leukocytes, human fibroblast (HT1080), E. coli, and S. epidermidis. The interfacial properties of the surface-modified Ti surfaces are analyzed and correlated with their antifouling properties. The new method and materials provide a more general, flexible, and robust way to produce an excellent nonfouling surface with adjustable interfacial structures of grafted polymers, which hopefully can be expanded to wider applications based on both the structure and surface superiorities.