Dynamic Protein–Metal Ion Networks: A Unique Approach to Injectable and Self‐Healable Metal Sulfide/Protein Hybrid Hydrogels with High Photothermal Efficiency.

Abstract: A new strategy is proposed to fabricate adaptable protein‐based hydrogel networks with both injectable and self‐healable properties. By mixing proteins and metal ions under alkaline conditions, the metal ions can crosslink proteins into protein–metal ion dynamic networks. Subsequently, the metal ions can react with the cysteine residues of protein to in situ form corresponding metal sulfide NPs with ultra‐small size, which leads to nanocomposite hydrogels with adaptable structures. This approach is general and a series of metal sulfide NP in situ embedded nanocomposite hydrogels were obtained. As an example, a Bi₂S₃–BSA hydrogel with tunable networks is shown to serve as an injectable, self‐healable photothermal agent for the treatment of tumors. Our finding paves a new avenue for the preparation of injectable and self‐healable hydrogels with potential applications in biomedicine. [ABSTRACT FROM AUTHOR]