Surface plasma modification and tropoelastin coating of a polyurethane co-polymer for enhanced cell attachment and reduced thrombogenicity

Polymers currently utilized for dermal and vascular applications possess sub-optimal biocompatibility which reduces their efficacy. Improving the cell-binding and blood-contacting properties of these polymers would substantially improve their clinical utility. Tropoelastin is a highly extensible extracellular matrix protein with beneficial cell interactive and low thrombogenic properties. We transferred these benefits to the polyurethane block copolymer Elast-Eon E2A through a specific combination of surface plasma modifications and coating with human tropoelastin. The cell-binding activity of bound tropoelastin was modulated by ion implantation of the underlying polymer, and correlated with surface hydrophobicity, carbon and oxygen content. This combined treatment enhanced human dermal fibroblast (HDF) and human umbilical vein endothelial cell (HUVEC) attachment, cytoskeletal assembly and viability, combined with elevated PECAM-1 staining of HUVEC cell junctions. The thrombogenicity of the polymer was ameliorated by tropoelastin coating. We propose that a combination of metered plasma treatment and tropoelastin coating of Elast-Eon can serve to improve the biological performance of implantable devices such as vascular conduits.