Conductive Electrochemically Active Lubricant-Infused Nanostructured Surfaces Attenuate Coagulation and Enable Friction-Less Droplet Manipulation

Micro/nanostructured materials and lubricant-infused surfaces, both inspired from structures found in nature, are ideally suited for developing self-cleaning and high surface area transducers for biosensing. These two classes of bio-inspired technologies are integrated to develop lubricant-infused electrodes designed to reduce biofouling. Chemical vapor deposition is used to create self-assembled monolayers of fluorosilane on gold-modified prestrained polystyrene substrates. After heat shrinking of the substrate, a lubricant is applied to produce a lubricant-infused nanostructured gold wrinkled surface with hydrophobic properties. These electrically conductive surfaces demonstrate high water contact (approximate to 150 degrees) and low sliding angles (<5 degrees). Moreover, combining these surfaces with passive magnetic actuators enables the actuation of super-paramagnetic microdroplets in frictionless and open channel conditions without needing full droplet submersion in an immiscible fluid. The fabricated nanostructured surfaces resist protein adhesion in a human plasma coagulation assay and significantly prolong clotting times and retain electrical conductivity, which is essential for electrical sensing applications. The developed hybrid interfaces are expected to have a wide range of applications in biosensing and biological sample preparation involving complex clinical and environmental samples.