Adaptive Elastin‐Like Hydrogel with Unidirectional and Controllable Anisotropic Actuation for Soft Robotics and Tissue Engineering

Abstract

Abstract Tissue‐mimetic scaffolds capable of actuating in response to environmental stimuli have great potential in soft robotics, especially if controllable at the molecular level. Elastin‐like recombinamers (ELRs) are biopolymers derived from natural tropoelastin intrinsically capable of responding to exogenous factors (e.g., pH, salt or temperature). A well‐designed and properly manufactured ELR scaffold should i) respond and adapt (actuate) according to external stimuli and ii) exhibit elastic properties to accommodate biomimetic actuation. However, current concepts typically use isotropic matrices, leading to isometric dimensional changes. In contrast, anisotropic actuation, a key feature in biological tissues at micro‐ and macroscopic level, allows directionally preferred responses but demands advanced design parallelled by an adequate fabrication scheme. Here, this challenge is addressed, by developing anisotropic elastin‐like scaffolds for directional, stimuli‐triggered actuation. Specifically, a fiber‐reinforced, elastin‐like tubular scaffold is developed with the capacity to actuate in an anisotropic and reversible manner in response to changes in solvent or temperature. Both the anisotropy and the degree of actuation can be efficiently controlled by changing the angle of the fiber‐reinforcement engineered within the elastin‐like matrix. The selection of the material and the straightforward fabrication make this scaffold versatile for applications that blends both soft robotics and tissue engineering.