Vascular grafts are essential for the management of cardiovascular disease. However, the lifesaving potential of these devices is undermined by thrombosis arising from material and flow interactions on the blood contacting surface. To combat this issue, antithrombogenic coatings have emerged as a promising strategy for modulating blood and graft interaction in vivo. Although an important determinant of graft performance, hemodynamics are frequently overlooked for in vitro testing of coatings and their translatability remains poorly understood. Herein, this limitation is addressed with a microscale graft on-a-chip platform incorporating vascular prosthesis and coatings with tuneable flow and surface conditions in vitro. As a proof of concept, the platform is used to test the thrombogenicity of a novel class of lubricant-infused surface (LIS) and antibody lubricant-infused (anti-CD34 LIS) coated expanded polytetrafluoroethylene (ePTFE) vascular grafts in the presence of arterial wall shear stress with and without endothelial cells. The findings suggest LIS ePTFE is thromboresistant under flow with significantly reduced fibrin(ogen) deposition, thrombin activity, and blood cell adhesion compared to uncoated controls. It is moreover apparent that the microscale properties of the device are advantageous for the testing and translation of novel antithrombogenic coatings and blood-contacting materials in general.

The surface fouling of biomedical devices has been an ongoing issue in healthcare. Bacterial and blood adhesion in particular, severely impede the performance of such tools, leading to poor patient outcomes. Various structural and chemical modifications have been shown to reduce fouling, but all existing strategies lack the combination of physical, chemical, and economic traits necessary for widespread use. Herein, a lubricant infused, hierarchically micro‐ and nanostructured polydimethylsiloxane surface is presented. The surface is easy to produce and exhibits the high flexibility and optical transparency necessary for incorporation into various biomedical tools. Tests involving two clinically relevant, priority pathogens show up to a 98.5% reduction in the biofilm formation of methicillin‐resistant Staphylococcus aureus and Pseudomonas aeruginosa. With blood, the surface reduces staining by 95% and suppresses thrombin generation to background levels. Furthermore, the surface shows applicability within applications such as catheters, extracorporeal circuits, and microfluidic devices, through its effectiveness in dynamic conditions. The perfusion of bacterial media shows up to 96.5% reduction in bacterial adhesion. Similarly, a 95.8% reduction in fibrin networks is observed following whole blood perfusion. This substrate stands to hold high applicability within biomedical systems as a means to prevent fouling, thus improving performance.