Asymmetrically Coordinated Cu Single-Atom Nanozyme to Accelerate Inflammation and Immune Homeostasis Modulation in...

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Catalysis

Background:

• Single-atom nanozymes (SANs) offer tunable properties but lag behind natural enzymes in catalytic performance due to symmetric coordination.
• Improving the electronic structure and coordination of SANs is crucial for enhanced biomedical applications.

Purpose of the Study:

• To engineer a novel bromine-doped copper-based SAN (Cu-BrN3/SAN@M) with asymmetric coordination.
• To investigate its enhanced catalytic activity and potential therapeutic effects in acute myocardial infarction.

Main Methods:

• Fabrication of Cu-BrN3/SAN@M with asymmetric coordination.
• Density functional theory (DFT) calculations to analyze electronic structure and catalytic mechanisms.
• In vitro and in vivo experiments to evaluate ROS scavenging, immune cell modulation, and therapeutic efficacy in an acute myocardial infarction model.

Main Results:

• Cu-BrN3/SAN@M demonstrated superior catalytic performance compared to symmetric Cu-N4/SAN@M.
• Asymmetric coordination optimized oxygen intermediate adsorption/desorption and facilitated reactive oxygen species (ROS) elimination.
• Cu-BrN3/SAN@M preserved cardiomyocyte viability, reprogrammed M1 macrophages to M2 phenotype, and amplified regulatory T cell activity, restoring immune homeostasis.

Conclusions:

• The engineered Cu-BrN3/SAN@M exhibits significantly enhanced catalytic activity due to asymmetric coordination and bromine doping.
• This SAN effectively modulates the inflammatory microenvironment and restores immune balance, showing promise for treating acute myocardial infarction.