Construction of an anticoagulant coating mimicking extracellular matrix for better surface blood compatibility and endothelialization of polyurethanes

Abstract

Polyurethane (PU) is widely used in cardiovascular implant devices. However, the surface hydrophilicity and bioactivity of polyurethanes are relatively insufficient, which can easily lead to non-specific protein adsorption, thrombosis, intimal hyperplasia, and endothelial dysfunction after implantation, thereby limiting their further clinical application. To address these constraints, the tannic acid/polylysine was first constructed on the polyurethane substrate to improve surface hydrophilicity while introducing surface amino groups. Then, heparin/laminin anticoagulant coating mimicking extracellular matrix (ECM) was further prepared through electrostatic adsorption and amide reaction. The modified coating significantly improved the wetting property of the PU surface, selectively promoted the adsorption of albumin while inhibiting the absorption of fibrinogen, and prevented platelet adhesion and activation, resulting in a notable boost in anticoagulant functionality. In addition, the bionic coating significantly enhanced endothelial cell (EC) adhesion, proliferation, and functional expression while effectively suppressing these processes in smooth muscle cells (SMCs), demonstrating its potential for promoting endothelial regeneration. The ECM-inspired coating developed in this study provides a novel solution for endowing blood-contacting polyurethanes with both endothelial regeneration and anticoagulant properties.