Bioinert polymer coatings resist nonspecific adhesion of proteins and cells by binding water molecules to form a hydration layer that attenuates thrombosis. Among different hydrophilic polymers such as dextran and tetraethylene glycol dimethyl ether, the most commonly used synthetic polymer is PEG. The repellency properties of PEG are highly dependent on its chain length and surface density. Some studies have reported enhanced protein and platelet adhesion on high-density PEG coated surfaces, whereas others found that increasing the surface grafting density creates a more porous and rougher surface coating that promotes cell adhesion. Despite the several promising antithrombogenic results of PEG coated implants, long-term in vivo tests revealed depletion of the coated PEG layer and degradation of its chain length and surface density due to oxidation by ROS. Therefore, PEG-coated surfaces are only useful for short-term applications. In contrast, vascular grafts coated with zwitterionic polymers have shown superior antithrombogenic results, due to their innate antifouling structure composed of a phospholipid rich cell membrane containing zwitterion head groups of carboxybetaine and phosphorylcholine. Studies of zwitterion structures for blood contacting applications have commonly used 2-methacryloyloxyethyl phosphorylcholine (MPC) due to its simple, high purity, and high-yield fabrication process, in addition to the high free-water fraction levels of its polymer chains that reduce the protein adsorption force at the interface (Figure ). 9,29 A study using a MPC coated poly(ester urethane)urea graft implanted as an aortic interposition grafts in rats for 24 weeks showed a tenfold decrease in platelet adhesion relative to uncoated grafts. Furthermore, immunohistochemical staining revealed formation of smooth muscle and endothelial cell markers on the coated grafts, as well as oriented collagen and elastin deposition. However, further in vivo experiments are required to substantiate the applicability of these coated grafts for complete remodelling into a native-like artery.