Iron decoration in binary graphene oxide and copper iron sulfide nanocomposites boosting catalytic antibacterial activity in acidic microenvironment against antimicrobial resistance.

The strong antimicrobial resistance (AMR) of multidrug-resistant (MDR) bacteria and biofilm, especially the biofilm with extracellular polymeric substance (EPS) protection and persister cells, not only renders antibiotics ineffective but also causes chronic infections and makes the infectious tissue difficult to repair. Considering the acidic properties of bacterial infection microenvironment and biofilm, herein, a binary graphene oxide and copper iron sulfide nanocomposite (GO/CuFeS NC) is synthesized by a surfactant free strategy and utilized as an alternative smart nanozyme to fight against the MDR bacteria and biofilm. For the GO/CuFeS NC, the iron decoration facilitates the well distribution of bimetallic CuFeS NPs on the GO surfaces compared to monometallic CuS NPs, providing synergistically enhanced peroxidase (POD)-like activity in acidic medium (pH 4 ∼ 5) and intrinsic strong near infrared (NIR) light responsive photothermal activity, while the ultrathin and sharp structure of 2D GO nanosheet allows the GO/CuFeS NC to strongly interact with the bacteria and biofilm, facilitating the catalytic and photothermal attacks on the bacterial surfaces.

Amyloid-like nanofibrous network confined and aligned ultrafine bimetallic nanozymes for smart antibacterial therapy.

Nanozyme-based antibacterial therapy (NABT) has emerged as a promising strategy to combat bacterial antimicrobial resistance. Engineering the noble metal nanozymes with strong bacterial capture and high catalytic activity for enhanced NABT is highly anticipated but still challenged. Herein, we developed hybrid nanozymes by engineering ultrafine bimetallic Au/Cu nanoparticles confined on the lysozyme amyloid-like nanofibrous networks (LNF).

Alternative Copper-Based Single-Atom Nanozyme with Superior Multienzyme Activities and NIR-II Responsiveness to Fight against Deep Tissue Infections.

Nanozymes are considered to represent a new era of antibacterial agents, while their antibacterial efficiency is limited by the increasing tissue depth of infection. To address this issue, here, we report a copper and silk fibroin (Cu-SF) complex strategy to synthesize alternative copper single-atom nanozymes (SAzymes) with atomically dispersed copper sites anchored on ultrathin 2D porous N-doped carbon nanosheets (CuN -CNS) and tunable N coordination numbers in the CuN sites ( = 2 or 4). The CuN -CNS SAzymes inherently possess triple peroxidase (POD)-, catalase (CAT)-, and oxidase (OXD)-like activities, facilitating the conversion of HO and O into reactive oxygen species (ROS) through parallel POD- and OXD-like or cascaded CAT- and OXD-like reactions.