Highly fluorescent and biocompatible iridium nanoclusters for cellular imaging

Area of Science:

• Nanotechnology
• Materials Science
• Biomedical Engineering

Background:

• Development of novel fluorescent probes for cellular imaging is crucial.
• Iridium-based materials offer unique photophysical properties for advanced applications.
• Intracellular markers require high fluorescence, biocompatibility, and specific localization.

Purpose of the Study:

• To synthesize and characterize highly fluorescent iridium nanoclusters for intracellular labeling.
• To evaluate the photophysical properties and biocompatibility of these nanoclusters.
• To investigate their potential as cytoplasmic markers and nanocarriers.

Main Methods:

• Synthesis of iridium nanoclusters (~2 nm) refluxed with 2,2'-binaphthol (BINOL).
• Characterization using UV-Visible, fluorescence, and lifetime decay measurements.
• In vitro cytotoxicity and cellular localization studies in HeLa cells.

Main Results:

• Synthesized iridium nanoclusters exhibit bluish-green emission with peaks at 449, 480, and 515 nm.
• High fluorescence quantum yield (0.36) and molar extinction coefficients (~10^6 M^-1cm^-1).
• Demonstrated good biocompatibility (IC50 ~100 μg/ml) and exclusive cytoplasmic localization.

Conclusions:

• Novel iridium nanoclusters are effective, biocompatible intracellular fluorescent markers.
• The nanoclusters show potential for targeted drug delivery and biomedical applications.
• This work opens avenues for iridium nanoparticle-based diagnostic and therapeutic tools.