pH-Responsive PtPdRuRhIr High-Entropy Alloy Nanozymes with Switchable Catalysis for Exceptional Inflammation Inhibition and Oral Bone Protection

Current therapies struggle to effectively eliminate resistant biofilms and resolve inflammation simultaneously. Here, we report the de novo design of high-entropy alloy (HEA, PtPdRuRhIr)-based Janus artificial enzymes with pH-gated redox biocatalysis for periodontitis therapy.

The multi-metal synergy stabilizes the d-band center, enabling pH-dependent transitions between peroxidase-like activities in acidic conditions and antioxidase-like functions at neutral pH. At the infection stage, the Janus artificial enzymes generate bactericidal reactive oxygen species (ROS), eliminating Staphylococcus aureus (S. aureus) and Porphyromonas gingivalis (P. gingivalis). While during the healing process, they scavenge excess ROS to alleviate oxidative stress and promote tissue regeneration.