A unique photochemical approach for polymer surface modification

Some materials that have desirable physical properties for certain applications have surface properties that limit their usefulness in those applications. A unique approach is described for modifying the surfaces of materials to tailor the surface characteristics for the desired application. This method uses reagents that are derivatized with photoactivatable groups. These photoactivatable reagents, when applied to polymeric substrates and activated, will form covalent bonds to most polymeric materials. This approach has been used to achieve such surface characteristics as permanent wettability, lubricity, passivation, increased hydrophobicity, and addition of functional groups such as ionic groups or reactive groups. For example, protein adsorption onto polysulfone membranes has been reduced by more than 90% by this method. Also, the bond strengths of silicone rubber to polyvinyl chloride, using cyanoacrylate adhesive, were increased by more than 18-fold by modifying the silicone rubber surface. The same approach is used to immobilize functional molecules for specific applications, such as antibodies and other receptors for affinity purifications or diagnostic applications, heparin for increasing hemocompatibility, cell attachment and growth factors for cell culture applications, and antimicrobials for reducing medical device-centered infections.