Engineering colloidally stable, highly fluorescent and nontoxic Cu nanoclusters via reaction parameter optimization

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Metal nanoclusters (NCs) exhibit unique properties due to their ultrasmall size (few to tens of atoms).
• Copper nanoclusters (Cu NCs) are earth-abundant and inexpensive but face challenges including oxidation, poor stability, and toxicity.
• Developing aqueous Cu NCs with high emission, stability, and low toxicity remains a significant hurdle.

Purpose of the Study:

• To establish a facile synthetic route for copper nanoclusters (Cu NCs) in an aqueous medium.
• To enhance photoluminescence intensity, colloidal stability, and reduce toxicity of Cu NCs.
• To explore the potential of synthesized Cu NCs as diagnostic probes and their applicability to other ligand systems.

Main Methods:

• Optimized a facile synthetic route by adjusting reaction parameters, focusing on the reducing agent concentration.
• Investigated optical characteristics and colloidal stability of the synthesized Cu NCs.
• Evaluated toxicity using both in vitro and in vivo models, including C. elegans.

Main Results:

• Achieved improved photoluminescence intensity and superior colloidal stability of Cu NCs through parameter optimization.
• Demonstrated a significant reduction in toxicity for the as-synthesized Cu NCs in biological models.
• Explored the utility of these Cu NCs as diagnostic probes in C. elegans and showed applicability to other ligands.

Conclusions:

• The optimized synthetic strategy successfully overcomes limitations of traditional Cu NCs, yielding enhanced properties.
• The developed Cu NCs exhibit reduced toxicity, improved stability, and high emission, making them promising for biomedical applications.
• This approach provides a versatile platform for designing advanced copper nanoclusters for diagnostics and other uses.