Bioinspired smart catalytic microneedle patch with structural color for infected wound management

Infected wounds remain a major clinical challenge due to persistent inflammation, excessive reactive oxygen species (ROS), and bacterial colonization. Here, we present a bioinspired catalytic microneedle (MN) patch that integrates antibacterial, anti-inflammatory, and real-time monitoring functions into a single platform. The patch possesses a hierarchical structure with spatially distributed nanocomponents: gold-modified barium titanate (AuB) in the MN tips enables ultrasound-triggered piezoelectric antibacterial activity, while cerium dioxide nanozyme (CeNP) in the backing layer efficiently scavenges ROS and mitigates inflammation. Of note, a structural color hydrogel incorporated in the backing layer provides visual, colorimetric indication of wound exudate, allowing timely patch replacement. Based on these features, it is demonstrated that the hierarchically structured MN patch exhibits robust antibacterial efficacy as well as anti-inflammatory treatment. In vivo evaluations further demonstrate its enhanced healing outcomes, which are characterized by improved tissue regeneration and accelerated resolution of inflammation. Collectively, these results highlight the potential of this smart hierarchical MN platform as an intelligent and multifunctional therapeutic strategy for efficient management of infected wounds.