Microfluidics is an emerging and multidisciplinary field that is of great interest to manufacturers in medicine, biotechnology, and chemistry, as it provides unique tools for the development of point-of-care diagnostics,...

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The ongoing problem with the thrombogenicity and poor tissue integration of synthetic vascular grafts demands the design of new surfaces that simultaneously suppress thrombosis and promote endothelialization. Lubricant-infused surfaces have shown outstanding results in preventing clot formation; however, their innate ability to completely block the surface, averts targeted binding of desired biomolecules. We report a new class of expanded polytetrafluoroethylene (ePTFE) vascular grafts that prevent blood coagulation and concurrently promote endothelial cell adhesion. This is made possible by direct silanization of anti-CD34 antibody with the coupling agent and subsequent conjugation of the silanized antibody to the ePTFE surface. In contrast to the conventional methods, we eliminated the need to chemically modify the ePTFE substrate for attaching the capturing ligand, and as a result preserved the innate surface properties of the ePTFE substrate. This is crucial for infiltrating the fluorine-based ePTFE substrate with a biocompatible perfluorocarbon-based lubricant and ultimately creating a functional and stable lubricant-infused layer. Compared to commercially available ePTFE vascular grafts and the ones coated using conventional methods, our developed ePTFE grafts significantly attenuate thrombin generation and blood clot formation and specifically capture endothelial cells from human whole blood while preventing nonspecific adhesion of undesirable proteins and cells. The developed technology can be applied to other biomarkers and biomaterials and can be tailored toward different biomedical applications where biofunctionality and targeted binding are of importance.

Specific ranges of dissolved oxygen (DO) concentrations must be maintained in a waterbody for it to be hospitable for aquatic animals. DO sensor designs can employ selectively permeable membranes to isolate DO from untargeted compounds or organisms in waterbodies. Hence, the DO concentration can be monitored and the health of the water can be evaluated over time. However, the presence of bacteria in natural waterbodies can lead to the formation of biofilms that can block pores and prevent analyte from permeating the membrane, resulting in inaccurate readings. In this work, we demonstrate the implementation of a fluorosilane-based omniphobic lubricant-infused (OLI) coating on a selectively permeable membrane and investigate the rate of biofilm formation for a commercially available DO sensor. Coated and unmodified membranes were incubated in an environment undergoing accelerated bacterial growth, and the change in sensitivity was evaluated after 40, 100, 250, and 500 h. Our findings show that the OLI membranes attenuate biofouling by 70% and maintain sensitivity after 3 weeks of incubation, further demonstrating that oxygen transfer through the OLI coating is achievable. Meanwhile, unmodified membranes exhibit significant biofouling that results in a 3.35 higher rate of decay in oxygen measurement sensitivity and an over 70% decrease in static contact angle. These results show that the OLI coating can be applied on commercially available membranes to prevent biofouling. Therefore, OLI coatings are a suitable candidate to suppress biofilm formation in the widespread use of selectively permeable membranes for environmental, medical, and fluid separation applications.

Micropatterned lubricant-infused biofunctional surfaces exhibit biofunctionality and omniphobicity simultaneously which leads to targeted cell attachment and alignment, both in surfaces and in microfluidic devices.