Crown Ether-Capped Gold Nanoclusters as a Multimodal Platform for Bioimaging.

Area of Science:

• Biomaterials Science
• Nanotechnology
• Biochemistry

Background:

• Biomolecule surface polarity is crucial for functions like folding and aggregation.
• Imaging diverse bio-interfaces requires markers sensitive to varying hydrophobicity.
• Existing imaging techniques may struggle with differentiating hydrophilic and hydrophobic environments.

Purpose of the Study:

• To synthesize and characterize ultrasmall gold nanoclusters capped with 12-crown-4 ligand.
• To evaluate the amphiphilic nature and solvent transfer capabilities of these nanoclusters.
• To demonstrate their application as multimodal probes for bioimaging of protein superstructures.

Main Methods:

• Synthesis and characterization of ultrasmall gold nanoclusters.
• Assessment of nanocluster amphiphilicity and stability in aqueous and organic solvents.
• Application in fluorescence microscopy and transmission electron microscopy for imaging amyloid structures.

Main Results:

• Successfully synthesized amphiphilic gold nanoclusters retaining integrity across solvents.
• Demonstrated effective staining of hydrophobic amyloid spherulites via fluorescence microscopy.
• Revealed nanoscale structural features of amyloid fibrils using transmission electron microscopy.

Conclusions:

• Crown ether-capped gold nanoclusters are promising multimodal imaging probes.
• Their amphiphilic character enables visualization of diverse bio-interfaces.
• These nanoclusters offer potential for advanced structural characterization of biomolecular assemblies.