Silver Ion-Triggered Fabrication of AuAg Bimetallic Aerogel Superstructures with Tailored Antibacterial Property for Advanced Anti-Infection Management

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.