Caitlin Howell, University of Maine
Liquid-infused surfaces inspired by the Nepenthes pitcher plant have recently been introduced as a new way to create materials with the bulk properties of solids and the surface properties of fluids. This approach is currently being used for a wide range of applications, including most prominently to create anti-fouling surfaces which function against challenging materials ranging from crude oil to ice. However, ongoing work is beginning to reveal the potential of liquid-infused surfaces for use in biomedical and biomaterials applications. The presence of a liquid layer presents a mobile physical barrier to infectious bacteria, preventing them from interacting with and irreversibly attaching to the solid surface below. When made on medical materials such as urinary catheters or hernia meshes, this strategy has been shown to effectively reduce the number of detectable bacteria in vivo. Toward more effective point-of-care diagnostics, the use of foldable paper substrates with a surface liquid layer permits the synergistic use of macroscale geometry with the fluid interface to controllably localize bacteria-containing samples. Finally, building an empty vasculature into the solid material beneath the liquid overlayer allows continuous self-replenishment of the surface liquid via diffusion, while also providing the capacity to temporally and spatially control a functional or bioactive diffusing compound.