Tandem Guest-Host Switching for Chemical-to-Electrochemical Signal Transduction

Area of Science:

• Supramolecular Chemistry
• Electrochemistry
• Chemical Sensing

Background:

• Bis-acridinium macrocycles and proflavine derivatives are key components in molecular recognition.
• Chemical-to-electrochemical signal transduction is crucial for developing advanced sensors.
• Understanding host-guest interactions is fundamental in supramolecular chemistry.

Purpose of the Study:

• To report a novel chemical-to-electrochemical signal transduction mechanism.
• To develop a selective electrochemical sensor for proflavine detection.
• To elucidate the tandem guest host switching (TANGHOS) mechanism.

Main Methods:

• Utilized 1H NMR and UV/vis spectroscopy for mechanistic studies.
• Employed computational analyses including DFT and molecular dynamics simulations.
• Developed a microkinetic model to understand the reaction dynamics.
• Grafted the macrocycle onto a gold surface for electrochemical sensing.

Main Results:

• Demonstrated a unique tandem guest host switching (TANGHOS) mechanism triggered by molecular recognition.
• Achieved selective electrochemical detection of proflavine from a mixture of polycyclic aromatic hydrocarbons.
• Observed amplified electrochemical responses due to surface confinement and reaction-coupled recognition.
• Confirmed the role of complementary acid-base properties and water-assisted transition states.

Conclusions:

• The TANGHOS mechanism provides a new pathway for chemical-to-electrochemical signal transduction.
• The bis-acridinium macrocycle-based sensor exhibits high selectivity and sensitivity for proflavine.
• Surface confinement enhances electrochemical detection capabilities, enabling sensitive analysis of complex mixtures.