Highly Reversible Supramolecular Light Switch for NIR Phosphorescence Resonance Energy Transfer

Area of Science:

• Supramolecular Chemistry
• Organic Electronics
• Materials Science

Background:

• Organic room-temperature phosphorescence (RTP) is gaining attention, but controllable supramolecular switches are scarce.
• Diarylethene derivatives and cucurbiturils are key components in developing advanced molecular systems.
• Phosphorescence Resonance Energy Transfer (PRET) offers unique mechanisms for light control.

Purpose of the Study:

• To design and synthesize single-molecule dual-fold supramolecular light switches.
• To investigate the regulatable phosphorescence and energy transfer properties of these novel systems.
• To explore applications in cell imaging and data encryption.

Main Methods:

• Synthesis of phenylpyridinium salts modified diarylethene derivatives (DTE-Cn).
• Formation of [3]pseudorotaxane complexes with cucurbit[8]uril (CB[8]).
• Construction of ternary supramolecular assemblies with Cy5 for PRET studies.

Main Results:

• Biaxial [3]pseudorotaxane demonstrated highly efficient and reversible RTP upon CB[8] binding (up to 99% quenching).
• Ternary supramolecular assemblies exhibited efficient PRET, enabling switchable near-infrared (NIR) emission.
• Successful application in mitochondria-targeted cell imaging and photocontrolled data encryption.

Conclusions:

• A novel supramolecular strategy utilizing energy transfer was developed for switchable phosphorescence.
• The designed systems offer a convenient approach for phosphorescent applications in biology and materials science.
• This work advances the development of smart organic materials with tunable photophysical properties.