Significance: The majority of deformable actuators rely on synthetic materials with stimuli-responsive properties to execute the system, limiting their use in vivo. We designed and built a new class of bionic actuator entirely out of biocompatible and biodegradable materials. Stimuli-responsive genetically engineered silk–elastin-like proteins (SELPs) and cellulose nanofibers (CNFs) are combined to fabricate an actuator system that could effectively respond to physical and chemical stimuli. Programmable and reversible deformations in response to the stimuli have been achieved with this actuator. The SELP/CNF actuator provides an option for fields such as in vivo biomedical soft robotics and biomimetic devices where biocompatibility, biodegradability, biomedical signals recognition, and durability are desired.

Silks spun by the arthropods are “ancient” materials historically utilized for fabricating high-quality textiles. Silks are natural protein-based biomaterials with unique physical and biological properties, including particularly outstanding mechanical properties and biocompatibility. Current goals to produce artificially engineered silks to enable additional applications in biomedical engineering, consumer products, and device fields have prompted considerable effort toward new silk processing methods using bio-inspired spinning and advanced biopolymer processing. These advances have redefined silk as a promising biomaterial past traditional textile applications and into tissue engineering, drug delivery, and biodegradable medical devices. In this review, we highlight recent progress in understanding natural silk spinning systems, as well as advanced technologies used for processing and engineering silk into a broad range of new functional materials.