Photo-Crosslinkable Polymeric Coatings Providing Chemically Versatile Reactive Surfaces on Various Substrates

We demonstrate a chemical route to attain simple, clean, scalable, photopatternable, chemically adjustable, and versatile systems to fabricate reactive organic thin films. Their surfaces exhibit effective biocompatibility, controlled reactivity, and processability on various surface types, i.e., photo-crosslinkable polymeric thin films with various functionalities, further applicable for the definition of surface activity for interfacing biological objects. The copolymers were synthesized with three monomers: a poly(ethylene glycol)-containing monomer, a monomer releasing a primary amine upon exposure to UV light, and a monomer bearing cyclic dithiocarbonate or glycidyl groups that are highly reactive with the amine. The resulting copolymers were processed with polar solvents such as water or alcohol for coating and were readily crosslinked under UV light illumination to form a highly stable molecular network, beneficial for defining selective reactive surfaces in a desired region on a variety of organic and inorganic substrates. The designed system was chemically versatile in immobilizing biologically relevant molecules on the surfaces by (i) postcrosslinking modification through the reaction of bovine serum albumin on the remaining surface reactive group with a primary amine in the protein and (ii) pre-crosslinking formulation with reactive gelatin that has the functionality to crosslink in the composite thin film. We further showed that the resulting coating on a glass or polystyrene substrate provided excellent biocompatibility and growth of C2C12 murine myocytes.