Photoresponsive supramolecular complexes as efficient DNA regulator

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Photochemistry

Background:

• Cucurbit[8]uril (CB[8]) is a macrocyclic host known for its strong binding affinities.
• Azobenzene and bispyridinium moieties are frequently used in photoresponsive molecular systems.
• Controlling molecular motion with external stimuli is a key goal in supramolecular chemistry.

Purpose of the Study:

• To synthesize and characterize novel supramolecular complexes involving CB[8] and photoresponsive guests.
• To investigate the light-driven dynamics and bistability of these supramolecular assemblies.
• To explore the potential applications of these complexes in regulating DNA interactions.

Main Methods:

• Controlled selective complexation in aqueous solution.
• Photocontrollable isomerization of azobenzene components.
• Characterization of supramolecular complexes and [2]pseudorotaxanes.
• Assessment of DNA binding and cleavage activities.

Main Results:

• Successful formation of two supramolecular complexes: trans-1⊂CB[8] and trans-2⊂CB[8].
• Demonstration of reversibly light-driven movements of CB[8] due to azobenzene isomerization.
• Observation of bistable behavior in the supramolecular complexes and [2]pseudorotaxanes.
• Evidence of the complexes acting as concentrators and cleavage agents for DNA molecules.

Conclusions:

• Novel photoresponsive supramolecular systems based on CB[8] were developed.
• The light-induced molecular movements offer precise control over complex behavior.
• These supramolecular complexes show promise for applications in DNA regulation and molecular machinery.