Injectable, Self‐healing, and 3D Printable Dynamic Hydrogels

Dynamic hydrogels are promising biomaterials for various biomedical and biotechnological applications due to their ability to change physicochemical properties and functions reversibly and/or sequentially in a time- or stimuli-dependent manner. In this study, a new class of dynamic hydrogels that are crosslinked by the in situ redox reactions of gold ions and disulfide groups are developed. Specifically, the gold ions initiate hydrogel formation via gold-thiol crosslinking, transforming the hydrogel from an injectable hydrogel to a mechanically stable and tough hydrogel. Moreover, the in situ nucleation and growth of gold nanoparticles within the crosslinked hydrogel networks further enhance electrical conductivity. The current work demonstrates the utility of these dynamic hydrogels for 3D printing and drug delivery.