Construction of a Mesoporous Ceria Hollow Sphere/Enzyme Nanoreactor for Enhanced Cascade Catalytic Antibacterial Therapy

ACS Appl Mater Interfaces. 2021 Sep 1;13(34):40302-40314. doi: 10.1021/acsami.1c10821. Epub 2021 Aug 20.

Abstract

Nanozyme has been regarded as one of the antibacterial agents to kill bacteria via a Fenton-like reaction in the presence of H2O2. However, it still suffers drawbacks such as insufficient catalytic activity in near-neutral conditions and the requirement of high H2O2 levels, which would minimize the side effects to healthy tissues. Herein, a mesoporous ceria hollow sphere/enzyme nanoreactor is constructed by loading glucose oxidase in the mesoporous ceria hollow sphere nanozyme. Due to the mesoporous framework, large internal voids, and high specific surface area, the obtained nanoreactor can effectively convert the nontoxic glucose into highly toxic hydroxyl radicals via a cascade catalytic reaction. Moreover, the generated glucose acid can decrease the localized pH value, further boosting the peroxidase-like catalytic performance of mesoporous ceria. The generated hydroxyl radicals could damage severely the cell structure of the bacteria and prevent biofilm formation. Moreover, the in vivo experiments demonstrate that the nanoreactor can efficiently eliminate 99.9% of bacteria in the wound tissues and prevent persistent inflammation without damage to normal tissues in mice. This work provides a rational design of a nanoreactor with enhanced catalytic activity, which can covert glucose to hydroxyl radicals and exhibits potential applications in antibacterial therapy.

Keywords: antibacterial therapy; catalysis; ceria; hollow sphere; mesoporous material.

MeSH terms

  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology
  • Anti-Bacterial Agents / therapeutic use*
  • Biocatalysis
  • Biofilms / drug effects
  • Cerium / chemistry
  • Cerium / therapeutic use
  • Enzymes, Immobilized / chemistry
  • Enzymes, Immobilized / therapeutic use
  • Escherichia coli / drug effects
  • Escherichia coli / physiology
  • Glucose / chemistry
  • Glucose Oxidase / chemistry
  • Glucose Oxidase / therapeutic use
  • Hydrogen Peroxide / chemistry
  • Hydroxyl Radical / metabolism
  • Metal Nanoparticles / chemistry
  • Metal Nanoparticles / therapeutic use*
  • Microbial Sensitivity Tests
  • Porosity
  • Staphylococcal Skin Infections / drug therapy*
  • Staphylococcus aureus / drug effects
  • Staphylococcus aureus / physiology

Substances

  • Anti-Bacterial Agents
  • Enzymes, Immobilized
  • Cerium
  • Hydroxyl Radical
  • ceric oxide
  • Hydrogen Peroxide
  • Glucose Oxidase
  • Glucose