Cycloparaphenylene-Helicene Conjugates with Donor-Acceptor Structure for Bioimaging

Area of Science:

• Organic Chemistry
• Supramolecular Chemistry
• Materials Science

Background:

• Helicenes are chiral aromatic compounds with unique optical properties.
• Cycloparaphenylenes are cyclic aromatic structures with tunable electronic properties.
• Combining these units can lead to novel functional materials.

Purpose of the Study:

• To design and synthesize novel cycloparaphenylene-helicene conjugates.
• To investigate their chiroptical properties and emission characteristics.
• To explore their potential for biological applications, specifically in cell imaging.

Main Methods:

• Synthesis via a highly efficient cyclocondensation reaction.
• Isolation of configurationally stable enantiomers using high-performance liquid chromatography (HPLC).
• Characterization of photophysical properties and cytotoxicity evaluation in A549 cells.

Main Results:

• Successful synthesis of two cycloparaphenylene-helicene conjugates with varying [7]helicene moieties.
• Isolation of configurationally stable P/M and P,P/M,M enantiomers.
• Exhibition of remarkable chiroptical properties and bright emission beyond 600 nm.
• Demonstration of stable presence and lysosomal colocalization in A549 cells with minimal cytotoxicity.

Conclusions:

• The synthesized conjugates possess unique photophysical properties due to the combined cycloparaphenylene and helicene units.
• These chiral carbon nanohoops show promise for live cell imaging applications.
• This work highlights the potential of chiral nanohoops in biological systems.