Heparin/collagen multilayer as a thromboresistant and endothelial favorable coating for intravascular stent.

Endothelialization and antithrombogenicity are two key issues in stent implantation. The layer-by-layer (LbL) deposition of anticoagulant heparin and cell compatible collagen was explored to develop a multilayered coating with synergic property of antithrombogenicity and fast endothelialization. The quartz crystal microbalance with dissipation (QCM-D), UV spectrometer, spectroscopic ellipsometry, scanning electron microscopy, and confocal laser scanning microscopy investigations indicate that the LbL technique, which based on molecular assembly, provides an easy way to develop a smooth, homogenous, and stable coating onto stents. In vitro blood clotting time tests and the platelet adhesion tests show that the multilayer-modified stents present good hemocompatibility. In vitro endothelial cell (EC) culture results show that the multilayer-modified surfaces accelerate the adhesion and proliferation of ECs. These results illustrate that a stent surface coating with properties of antithrombogenicity and EC preference was obtained via heparin/collagen multilayer modification. This surface coating may have great potential in facilitating in situ endothelialization of blood contacting materials.