A Three-Component Assembly Promoted by Boronic Acids Delivers a Modular Fluorophore Platform (BASHY Dyes)

Area of Science:

• Organic Chemistry
• Materials Science
• Biotechnology

Background:

• Fluorescent dyes are essential tools for biological imaging.
• Developing novel dyes with specific photophysical properties is crucial for advanced applications.
• Boronic acids and Schiff-base ligands offer versatile platforms for dye synthesis.

Purpose of the Study:

• To develop novel fluorescent dyes using boronic acids and Schiff-base ligands for live cell bioimaging.
• To investigate the structural and photophysical properties of the synthesized dyes.
• To evaluate the potential of these dyes for nanoparticle formulation and selective cellular staining.

Main Methods:

• Modular assembly of boronic acids with Schiff-base ligands.
• Synthesis of boronic acid salicylidenehydrazone (BASHY) dyes.
• Characterization of photophysical properties (emission, quantum yield, brightness).
• Preparation and evaluation of poly(lactide-co-glycolide) nanoparticles.
• Cytotoxicity assays and cellular imaging in HeLa cells.

Main Results:

• Achieved straightforward synthesis of diverse BASHY dyes with yields up to 99%.
• Demonstrated polarity-sensitive green-to-yellow emission with high quantum yields (up to 0.6) and brightness (up to 54,000 M(-1) cm(-1)).
• Successfully prepared non-cytotoxic, stable, highly fluorescent nanoparticles from BASHY dyes.
• Showed selective staining of lipid droplets in HeLa cells without cytotoxicity or plasma membrane interference.

Conclusions:

• BASHY dyes possess excellent structural and photophysical properties suitable for live cell bioimaging.
• The synthesized dyes are effective for creating fluorescent nanoparticles for cellular delivery.
• BASHY dyes demonstrate potential as selective fluorescent stains for lipid droplets in biological systems.