Bioinspired Injectable Self-Healing Hydrogel Sealant with Fault-Tolerant and Repeated Thermo-Responsive Adhesion for Sutureless Post-Wound-Closure and Wound Healing

Highlights

• Mussel and brown algae inspired dual-bionic bioadhesive cross-linked by dynamic bonds exhibits good self-healing capacity and sufficient adhesive strength. And the adhesive hydrogel shows temperature-dependent reversible adhesive behavior, and could achieve fault-tolerate adhesive application and repeated tissue adhesion.

• The coordination interaction between ferric ions and protocatechualdehyde equips the hydrogel with photothermal antibacterial effect.

• The injectable adhesive with antioxidation and good hemostatic effect shows promising application in tissue sealant and wound closure.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40820-022-00928-z.

Abstract

Hydrogels with multifunctionalities, including sufficient bonding strength, injectability and self-healing capacity, responsive-adhesive ability, fault-tolerant and repeated tissue adhesion, are urgently demanded for invasive wound closure and wound healing. Motivated by the adhesive mechanism of mussel and brown algae, bioinspired dynamic bonds cross-linked multifunctional hydrogel adhesive is designed based on sodium alginate (SA), gelatin (GT) and protocatechualdehyde, with ferric ions added, for sutureless post-wound-closure. The dynamic hydrogel cross-linked through Schiff base bond, catechol-Fe coordinate bond and the strong interaction between GT with temperature-dependent phase transition and SA, endows the resulting hydrogel with sufficient mechanical and adhesive strength for efficient wound closure, injectability and self-healing capacity, and repeated closure of reopened wounds. Moreover, the temperature-dependent adhesive properties endowed mispositioning hydrogel to be removed/repositioned, which is conducive for the fault-tolerant adhesion of the hydrogel adhesives during surgery. Besides, the hydrogels present good biocompatibility, near-infrared-assisted photothermal antibacterial activity, antioxidation and repeated thermo-responsive reversible adhesion and good hemostatic effect. The in vivo incision closure evaluation demonstrated their capability to promote the post-wound-closure and wound healing of the incisions, indicating that the developed reversible adhesive hydrogel dressing could serve as versatile tissue sealant.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40820-022-00928-z.