Silver Ion-Triggered Fabrication of AuAg Bimetallic Aerogel Superstructures with Tailored Antibacterial Property for...

The clinical application of antibiotic-free, Ag-based antibacterial agents remains a significant challenge due to uncontrolled Ag⁺-release and limited long-term antibacterial activity. Herein, a robust antibacterial platform based on Ag⁺-triggered self-assembled AuAg aerogel is developed for advanced infectious wound management. By employing ultrasmall-sized gold nanoclusters (AuNCs) as building blocks, Ag⁺ serves as the gelator to actively interact with AuNCs through multiple types of interactions, including coordination, metallophilic interactions, and the Anti-Galvanic Reduction reaction. As a result, novel 3D self-supported porous AuAg bimetallic aerogels can be controllably fabricated. The obtained AuAg aerogels exhibit tunable ligament size in the range of 8.5-32.0 nm, adjustable composition, and controllable antibacterial properties. Mechanistic studies reveal that the initial concentration of Ag⁺ plays a critical role in determining the nanostructure and composition of AuAg aerogels as well as their antibacterial efficacy. A higher concentration of Ag⁺ enables a more stable and sustainable release of Ag⁺ from AuAg aerogels, leading to long-term and on-demand anti-infection effects. Consequently, these AuAg aerogels display significant anti-infection, anti-inflammation, and pro-regenerative effects for the treatment of infectious wounds, as demonstrated by the in vivo studies. This work provides a new approach for reasonable design and flexible manipulation of metal aerogels for versatile biomedical applications.