Spatially-controlled surface activation of preformed polymers

Polymers are increasingly being engineered for their properties as biomaterials. They offer significant versatility and wide-ranging physical properties compared to metals; however, the lack of an appropriate interface between polymer surfaces and bodily tissue remains a substantial problem. Methods were developed that enable the covalent attachment of organic molecules to many polymer surfaces. Zirconium-amidate and --carbamate complexes were characterized in solution by 1H and 13C NMR; they were subsequently formed on polyamides (Nylon 6/6, silk, collagen) and polyurethanes (polyhexamethylene hexylene urethane, TecoflexRTM); infrared spectroscopy and contact angle analysis allowed their surface characterization. RGD-activated polymers showed increased cell attachment and spreading in vitro. Mixed zirconium oxide/alkoxide adhesion layers were formed on polyethylene terephthalate (PET), polyetheretherketone (PEEK), and KaptonRTM polyimide surfaces that allowed attachment of organic molecules or copper metal. Fluorescence spectroscopy enabled quantification of surface yields for all organic reactions, and EDX facilitated confirmation of surface Cu species. New chemical methods for photolithography enabled spatial control of polymer surface activation to bond organics and copper metal. Spatially-controlled attachment of RGD to polyamides and PET enabled control of cell attachment and shape.