Endothelial Inspired Polymeric Coating

Commentary on:

Preparation and characterization of polymeric coatings with combined nitric oxide release and immobilized active heparin

6 June 2005 - ScienceDirect database

Link to study here

In this study, a biomimetic approach was taken in order to improve the blood compatibility of polymeric materials used to construct or coat a variety of blood-contacting medical devices, such as vascular grafts. One of the major causes of graft failure remains lack of a functional endothelium on the luminal surface of a synthetic vascular graft, which leads to acute thrombosis and subsequent occlusion of the vessel. By mimicking the nonthrombogenic properties of the endothelial cell layer that lines the inner wall of healthy blood vessels, a new dual acting polymeric coating was produced. This biomimetic polymeric coating mimics the function of the endothelial layer by the anti-platelet component, nitric oxide, and anti-coagulant component, heparin.

The blood compatible coating is a fine example of the promise of biomimetics in the field of artificial vascular graft development of the biomedical industry. The surface composition of a biomaterial can have an important influence on biologic responses. Changing the surface chemistry of a synthetic graft by coating it with endothelial cell components is a great way to enhance thromboresistivity and further improve the vascular graft’s patency rate. In particular, this biomimetic coating may prove to be more of a solution for small-diameter grafts, since large-diameter vascular grafts remain excellent for more than ten years after implantation, while small-diameter vascular grafts typically occlude rapidly upon implantation.

Even though this particular biomimetic coating is one of many ways that biomedical engineers have developed in order to improve current polymer materials used to construct a variety of blood-contacting medical devices, it is a risk-averse method. By understanding the biology of the endothelial layer and its ability to control thrombosis, it makes sense to apply an endothelial inspired biomimetic approach. Biomimetic models, such as this coating, are used because they already have the biological proven research to ensure their feasibility. It’s just a matter of being able to properly replicate them.