Silk protein–based smart hydrogels for biomedical applications

Silk is a naturally occurring protein polymer that is mainly made up of silk fibroin (SF) and silk sericin. Hydrogels prepared using silk proteins are among the most extensively explored scaffold forms for drug delivery and tissue engineering applications. These hydrogels have exceptional structural properties and exhibit essential characteristics, including controlled degradation, superior processability, biocompatibility, mechanical, and tunable performance. Recently, stimuli-responsive silk hydrogels have been explored for a variety of applications. These hydrogels can exhibit stimuli-responsive behaviors that are brought on by changes in pH, temperature, light, electricity, magnetic field, and biomolecules. In this chapter, we begin by introducing the silk hydrogel preparation. We further discuss the preparation and characteristics of the smart silk protein hydrogels. Further, the applications of these stimuli-sensitive hydrogels in biomedicine, tissue engineering, soft robotics, and biomachinery disciplines are discussed.