Rotaxane and catenane host structures for sensing charged guest species

Area of Science:

• Supramolecular Chemistry
• Nanotechnology
• Chemical Sensing

Background:

• Mechanically interlocked architectures (rotaxanes and catenanes) show promise as molecular switches and shuttles.
• Their intricate host cavities offer a novel platform for molecular recognition and sensing applications.
• Exploiting dynamic properties of these molecules enables sophisticated and selective sensor responses.

Purpose of the Study:

• To describe the use of rotaxane and catenane host systems for binding charged guest species.
• To develop sensing capabilities through integrated optical or electrochemical reporter groups.
• To focus on the challenging task of selective anion sensing using mechanically interlocked structures.

Main Methods:

• Synthesis of rotaxanes and catenanes using discrete anionic templation.
• Incorporation of optical (transition metals, lanthanides, organic fluorophores) and electrochemical (ferrocene) reporter groups.
• Fabrication of anion-templated rotaxanes and catenanes on gold electrode surfaces for self-assembled monolayers.

Main Results:

• Demonstrated selective anion recognition by interlocked host systems with geometrically restrained binding cavities.
• Developed electrochemical and optical anion sensors with high selectivity.
• Showcased anion-induced conformational changes for signal transduction and electrochemical responsiveness of surface-confined sensors.

Conclusions:

• Mechanically interlocked molecules offer superior molecular recognition capabilities for chemical sensing.
• Integration of reporter groups enables functional host-guest sensory systems.
• Advances in synthesis and surface confinement are crucial for developing robust and reusable sensory devices.