Development and Characterization of Biostable Hydrogel Robotic Actuators for Implantable Devices: Tendon Actuated Gelatin

While the field of medical device design has made tremendous progress in recent decades, implantable devices continue to be plagued by the body’s immune response and fibrosis. The field of soft robotics uses low modulus materials that compliance match surrounding tissues to help address this issue. Traditionally, silicone has been the material of choice for soft robots. Although durable and elastic, implanted silicone often leads to fibrosis. To advance the use of soft robotics in medical devices, new materials must be explored. We hypothesize that protein-based soft robotic actuators hold promise for implantable medical devices by not only matching moduli surrounding tissues but also providing physiologically relevant chemical cues. Biocompatible soft actuators that achieve the functionality of silicone counterparts may promote integration with host cells and support long-term implant safety. Additionally, controlled degradation may hold promise for post-surgical support devices or drug delivery. Here, we develop and characterize crosslinked gelatin (GEL) actuators. The development of biomaterial soft actuators with properties comparable to synthetic analogues expands the applications of soft robotic devices for medical devices and healthcare applications.