Atomic-Scale Full-Size Engineering of Platinum Nanozymes Enables High-Efficiency Catalytic Therapy

Metal particle size has a significant influence on the activity of nanozymes, yet size-dependent nanozymatic catalysis under the same metal loadings in full scale (from single atom, cluster to nanoparticle) is a challenging task and has been rarely reported. Herein, porous SiO₂ nanoflower surface-confined Pt-based nanozymes with the same metal loadings but different particle sizes were rationally designed and synthesized for antibacterial and cascade catalytic tumor therapy. The particle size–activity relationship is well established, presenting a volcanic curve, and the Pt_NC/SiO₂ nanocluster (NC) nanozyme exhibits optimized peroxidase-like activity and bactericidal efficacy compared with SAzyme and nanozyme. Furthermore, a synergistic therapeutic platform (Lap@Pt_NC/SiO₂) is constructed through the adsorption of the prodrug β-lapachone (Lap), achieving high-efficiency cascade enzymatic catalysis for tumor therapy thereby. The cluster nanozymes not only present optimized activity during the full-size engineering but also demonstrate great potential in next-generation antibacterial and tumor catalytic therapy.