Surface-Engineered Gold Nanoclusters with Biological Assembly-Amplified Emission for Multimode Imaging.

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Molecular Imaging

Background:

• Gold nanoclusters (AuNCs) show promise for bioimaging but require functionalization for specific applications.
• Ligand engineering is crucial for improving AuNC stability, signal amplification, and biocompatibility.

Purpose of the Study:

• To develop bifunctional ligand-engineered AuNCs as signal-amplifying reporters for multimode imaging.
• To enhance detection sensitivity and reliability for cell-expressed antigens and structures.

Main Methods:

• Engineered AuNCs using modified streptavidin (SA) and biotin alkyl acid ligands (AuNC-SA, AuNC-biotin).
• Utilized zwitterionic ligands to promote bioassembly and prevent nonspecific adsorption.
• Employed one-photon, two-photon, and fluorescence lifetime imaging techniques.

Main Results:

• Achieved stable emission and resisted aggregation-induced quenching through biological self-assembly.
• Demonstrated a large two-photon absorption cross-section and long fluorescence lifetime.
• Successfully converted cell-expressed antigen-induced protein-binding events into detectable AuNC assembly signals.

Conclusions:

• Bifunctional ligand-engineered AuNCs serve as effective signal-amplifying reporters for multimode imaging.
• The developed AuNCs offer a simple, sensitive, and reliable method for comprehensive antigen and cell structure assays.
• This approach holds potential for advancing diagnostic and research applications in molecular imaging.