Naphthylimide Chemosensor Based on Anion-π Interactions: A Promising Tool for Environmental Monitoring

Area of Science:

• Environmental chemistry
• Analytical chemistry
• Supramolecular chemistry

Background:

• Chemosensors are crucial for environmental monitoring, especially for detecting ions like fluoride.
• Elevated fluoride levels pose health risks, including damage to tooth enamel.

Purpose of the Study:

• To develop and characterize a selective chemosensor for fluoride ion detection.
• To elucidate the interaction mechanism between the chemosensor and fluoride ions.

Main Methods:

• Spectroscopic techniques including UV-vis and fluorescence spectroscopy.
• Nuclear Magnetic Resonance (NMR) titration studies (¹H NMR).
• Theoretical calculations to support experimental findings.

Main Results:

• A naphthylimide derivative was synthesized as a selective fluoride chemosensor.
• UV-vis spectroscopy indicated a high stability constant (K₁₁ = 2.0 × 10⁴ mol dm⁻³) for the chemosensor with fluoride.
• ¹H NMR titrations and theoretical calculations confirmed an anion-π interaction mechanism involving the benzene moiety.

Conclusions:

• The developed chemosensor demonstrates high selectivity and stability for fluoride detection.
• The anion-π interaction mechanism is key to the sensor's functionality.
• This cost-effective and user-friendly chemosensor shows significant promise for environmental and analytical applications.