Engineering of endothelial cell response on biphasic polyurethane matrix

Polyurethanes (PUs) are composed of soft and hard segments, and segmental interactions induce biphasic morphologies which can influence endothelial cell (EC) organization by regulating cell–matrix and cell–cell interactions. In this study, we explored this effect using poly(caprolactone) (PCL)-based PU, where the soft segment was composed of PCL and the hard segment was composed of hexamethylene diisocyanate (HDI) and L-tyrosine-based dipeptide (DTH). The composition of the PUs was varied by altering the PCL molecular weight and correspondingly, different phase morphologies were observed. Organization and functional state of ECs on these PUs showed that composition and phase morphology of PU have a significant effect on cellular response. The ECs formed an organized network with cord-like structures which resulted in interconnected loops when soft and hard segment fractions were phase-separated. VE-cadherin (for cell–cell adherence) and vinculin (for cell–matrix focal adhesion) localized at the tip of int...