Heterostructure Nanozyme with Hyperthermia‐Amplified Enzyme‐Like Activity and Controlled Silver Release for Synergistic Antibacterial Therapy

Oxygen-vacancy-enriched MoOx spontaneously reduces Ag (I) into Ag (0). The introduction of Ag NPs enhances the photothermal effect of Ag/G-MoOx heterostructure nanozyme that further improves the oxidase-like activity and Ag ions release. The resultant Ag/G-MoOx heterostructure nanozyme shows synergistically amplified antibacterial therapy against multidrug-resistant bacteria.

Abstract

Heterostructure nanozymes as antibiotic-free antimicrobial agents exhibit great potential for multidrug-resistant (MDR) bacterial strains elimination. However, realization of heterostructure antimicrobials with enhanced interfacial interaction for synergistically amplified antibacterial therapy is still a great challenge. Herein, oxygen-vacancy-enriched glucose modified MoO _x (G-MoO _x ) is exploited as a reducing agent to spontaneously reduce Ag (I) into Ag (0) that in situ grows onto the surface of G-MoO _x . The resultant Ag doped G-MoO _x (Ag/G-MoO _x ) heterostructure displays augmenting photothermal effect and NIR-enhanced oxidase-like activity after introducing Ag nanoparticles. What's more, NIR hyperthermia accelerate Ag⁺ ions release from Ag nanoparticles. Introduction of Ag greatly enhances antimicrobial activities of Ag/G-MoO _x against MDR bacteria, especially the hybrid loading with 1 wt% Ag NPs exhibiting antibacterial efficacy up to 99.99% against Methicillin-resistant Staphylococcus aureus (MRSA, 1×10⁶ CFU mL⁻¹).