Physical properties of artificial extracellular matrix protein films prepared by isocyanate crosslinking

Artificial extracellular matrix proteins, genetically engineered from elastin- and fibronectin-derived repeating units, were crosslinked with hexamethylene diisocyanate in dimethylsulfoxide. The resulting hydrogel films were transparent, uniform, and highly extensible. Their tensile moduli depended on crosslinker concentration and spanned the range characteristic of native elastin. The water content of the films was low ( 27%), but the temperature-dependent swelling behavior of the crosslinked materials was reminiscent of the lower critical solution temperature property of the soluble polymers.