Biocompatible Ruthenium Single-Atom Catalyst for Cascade Enzyme-Mimicking Therapy

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Materials Science

Background:

• Developing single-atom enzymes (SAEs) with high activity, stability, and biocompatibility is critical for cancer therapy.
• Existing SAEs face challenges in achieving optimal performance for therapeutic applications.

Purpose of the Study:

• To rationally construct highly active and stable ruthenium single-atom enzymes (Ru SAEs) using biocompatible carbon dots for enhanced tumor therapy.
• To investigate the multi-enzyme-like activities and mechanism of action of the developed Ru SAEs.

Main Methods:

• Synthesized Ru SAEs by loading ruthenium single atoms onto biocompatible carbon dots.
• Evaluated the oxidase, peroxidase, and glutathione oxidase-like activities of Ru SAEs.
• Assessed the efficacy of Ru SAEs in generating reactive oxygen species (ROS) and depleting glutathione.
• Utilized theoretical calculations to elucidate the mechanism of H2O2 activation by Ru SAEs.

Main Results:

• Achieved Ru SAEs with superior multi-enzyme-like activity and stability.
• Demonstrated that Ru SAEs mimic oxidase, peroxidase, and glutathione oxidase, leading to amplified ROS generation and glutathione depletion.
• Ru SAEs exhibited excellent peroxidase-like activity (7.5 U/mg), significantly outperforming Ru/C.
• Theoretical analysis confirmed efficient H2O2 activation via electron transfer in Ru SAEs, producing hydroxyl radicals (•OH).

Conclusions:

• The developed Ru SAEs show significant potential for cancer therapy due to their enhanced enzyme-like activities and mechanism of action.
• This study provides a promising strategy for designing advanced SAEs for biomedical applications, particularly in tumor treatment.
• The use of biocompatible carbon dots as carriers offers a pathway for creating stable and effective single-atom enzyme therapeutics.