In this project, we were able to develop a material with a unique mechanical behavior that mimics the actin filaments cross-linking in cells in response to deformation that leads to an increase in stiffness via a mechanism called strain-stiffening. Our cell-inspired material offers a strain-stiffening effect that arises from the structure that emulates filament interconnection in a cell’s cytoskeleton that takes place upon deformation. Silicone was used as a synthetic material with a structure comprising parallel and flexible slats that mimic single actin fibers through coming into contact with each other when strained. The slats resemble the cross-linking and bundling of cellular actin fibers due to applied forces to provide additional stiffness to the structure.
The strain-stiffening mechanism in our material is reversible, material- and deformation-speed independent and allows for the attenuation of the effect through changing the structure size and geometry. With a relatively easy, high-throughput process, we were able to fabricate structures in varying scales (µm to cm). Both computational modelling and experimental investigations were performed in this study to examine the impact of different geometrical parameters on the strain-stiffening mechanism of our structure. As this mechanism is an intrinsic feature in our material that requires no additional chemical reagents, these structures have great potential in the field of orthotics and soft robotics systems. Contacts to industry have been made and are being continued.
