Plasmonic Supramolecular Nanozyme-Based Bio-Cockleburs for Synergistic Therapy of Infected Diabetic Wounds

Abstract

Diabetic wounds are a major devastating complication of diabetes due to hyperglycemia, bacterial invasion, and persistent inflammation, and the current antibiotic treatments can lead to the emergence of multidrug-resistant bacteria. Herein, a bimetallic nanozyme-based biomimetic bio-cocklebur (GNR@CeO₂@GNPs) is designed and synthesized for diabetic wound management by depositing spiky ceria (CeO₂) shells and gold nanoparticles (GNPs) on a gold nanorod (GNR) nanoantenna. The plasmonic-enhanced nanozyme catalysis and self-cascade reaction properties simultaneously boost the two-step enzyme-mimicking catalytic activity of GNR@CeO₂@GNPs, leading to a significant improvement in overall therapeutic efficacy rather than mere additive effects. Under the glucose activation and 808 nm laser irradiation, GNR@CeO₂@GNPs material captures photons and promotes the transfer of hot electrons from GNR and GNPs into CeO₂, realizing a "butterfly effect" of consuming local glucose, overcoming the limited antibacterial efficiency of an individual PTT modality, and providing substantial reactive oxygen species. In vitro and in vivo experiments demonstrate the material's exceptional antibacterial and antibiofilm properties against Gram-negative and Gram-positive bacteria, which can reduce inflammation, promote collagen deposition, and facilitate angiogenesis, thereby accelerating wound healing. This study provides a promising new strategy to develop plasmonic-enhanced nanozymes with a catalytic cascade mode for the antibiotic-free synergistic treatment of infected diabetic wounds.

Keywords: antibacterial; diabetic wound healing; heterostructures; nanomedicine; plasmonic.