Photothermal-Activated Antibacterial Amyloid-Polyphenol-Iron Hydrogels for Synergistic Wound Healing.

Abstract

The design and development of stimuli-responsive hydrogels with anti-inflammatory and antibacterial properties have triggered significant progress in wound healing treatment. Herein, we report a thermally triggered supramolecular hydrogel combining potent antibacterial activity with photothermal functionality. The incorporation of Fe³⁺ ions into tannic acid (TA), both bound to lysozyme amyloid fibril (Lys AF) networks, serves a dual role: enabling rapid gelation and conferring efficient photothermal transduction. This dynamic self-assembly is primarily driven by thermally enhanced metal-ligand coordination between Fe³⁺ and the amyloid-polyphenol complex (LT), while hydrogen bonding contributes to network stabilization. This mechanism is amplified at elevated temperatures and under optimized concentrations. Notably, the formed amyloid-polyphenol-iron (LTFe) hydrogel exhibits exceptional photothermal conversion efficiency (88.56%), robust cycling stability, excellent biocompatibility, and potent antibacterial efficacy against both Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria. In vivo studies confirmed that LTFe eradicated pathogens, suppressed inflammatory cytokines, and accelerated wound regeneration. Overall, our work introduces a versatile strategy for designing high-efficiency and high-biocompatibility NIR-responsive hydrogel systems.