Molecular Hemocompatibility of Graphene Oxide and Its Implication for Antithrombotic Applications

Surface-induced blood clotting is one of the major problems associated with the long-term use of blood-contacting biomedical devices. Central to this obstructive blood clotting is the adsorption of plasma proteins following the interactions between blood and material surface. Of all proteins circulating in the blood plasma, albumin and fibrinogen are the two important proteins regulating the blood-material interaction. As such, the adsorption of plasma proteins has been used as an indicator for the assessment of the blood compatibility of the biomedical devices. Numerous nanomaterials have been developed for antithrombotic surface coating applications, including the 2D graphene and its derivatives. Here, the antithrombotic property of albumin-functionalized graphene oxide (albumin-GO) and its potential for antithrombotic coating application under flow are investigated. The loading capacities, conformational changes, and adsorptions of albumin and fibrinogen on GO are probed. It is observed that GO possesses a high loading capacity for both proteins and simultaneously, it does not disrupt the overall secondary structure and conformational stability of albumin. Both albumin and fibrinogen adsorb well on the surface of GO. Subsequently, it is demonstrated that the albumin-functionalized GO possesses enhanced antithrombotic effect and may potentially be used as an antithrombotic coating material of blood-contacting devices under dynamic flow.