Biomimetic Nanostructured Surfaces with Designer Mechanics and Geometry for Broad Applications

A powerful fabrication platform for a wide range of biomimetic, high-aspect-ratio nanostructured surfaces is introduced. The principles of soft lithography are extended into a double-mold replication process, whereby a master topography is mapped onto an elastomeric inverse mold and replicated in arbitrary multiple material and stiffness gradients, and an array of modified geometries. Control of geometry via deformation of the inverse mold and control of stiffness via prepolymer mixing are discussed. New capabilities enabled by our approach include biomimetic actuation/sensor arrays with programmable biases, precisely tunable mechanical and geometric properties for optical or wetting applications, and flexible curved substrates. Indeed, flexibly anchored ciliary high-aspect-ratio nanostructures are now possible, and a proof-of-principle is described.