Device-associated clot formation and poor targeted cell-adhesion are ongoing problems in permanent blood-contacting medical implants. The recent concept of lubricant-infused surfaces has shown promising results in preventing non-specific adhesion and attenuating clot formation on biomaterials. However, the existing surface models do not express biofunctional features, a crucial requirement when designing surface coatings for permanent medical implants such as vascular grafts, stents and mechanical heart valves. The main objective of this thesis is to design and develop novel biofunctional lubricant-infused surface coatings that would simultaneously prevent device-associated thrombosis and actively promote surface biointeractions.

Three main approaches to incorporate biofunctionality into lubricant-infused surfaces are presented in this thesis:​ (1) Developing biofunctional lubricant-infused surface coatings by creating self-assembled monolayers using fluoro and aminosilane molecules. (2) Creating non-fluorosilanized biofunctional lubricant-infused ePTFE vascular grafts by exploiting the innate chemical properties of the ePTFE grafts and biofunctionalizing the surfaces using silanized bio-inks. (3) Creating fluorinated biofunctional lubricant-infused PET grafts with “built-in” functional groups using oxygen plasma treatment. Using these three modification procedures, for the first time, we were able to generate lubricant-infused surfaces, that expressed biofunctional and targeted-binding features. In the first modification technique, by tuning the ratio between the fluorosilane and aminosilane molecules, we were able to incorporate functional groups on the surfaces without compromising the lubricant-infused repellency properties of the modified substrates. In the second modification technique, we created non-fluorosilanized biofunctional lubricant-infused ePTFE grafts by eliminating the need to chemically modifying the surface with silane molecules. Our designed surfaces were further biofunctionalized using our developed silanized bio-inks. Lastly, in order to created fluorinated biofunctional lubricant-infused PET grafts, we developed the third modification process, where fluorinated PET surfaces were hydroxyl-terminated using oxygen plasma treatment, and biofunctionalized using silanized bio-inks.

The designed surfaces using the three proposed modification procedures had excellent repellency properties by attenuating plasma and blood clot formation, thrombin generation and preventing non-targeted adhesion of proteins and cells. In addition, our developed surfaces were biofunctional and were able to actively promote targeted binding of endothelial cells.

With the new surface coatings created in this thesis, lubricant-infused surfaces with excellent repellency properties and biofunctional features can be achieved and applied to blood-contacting medical devices where preventing non-specific adhesion and promoting targeted binding are of immense importance.