Selective Turn-On Luminescent Recognition of Perchlorate Ion Using Pyridyl-Benzimidazole-Based Probe

Area of Science:

• Analytical Chemistry
• Environmental Science
• Materials Science

Background:

• Anions are vital in environmental, chemical, and biological systems.
• Rising perchlorate (ClO4-) production necessitates efficient detection methods.

Purpose of the Study:

• To synthesize and characterize a novel pyridyl-benzimidazole-based luminescent probe (RSB1).
• To achieve selective and sensitive detection of perchlorate ions using the RSB1 probe.

Main Methods:

• Synthesis and characterization of RSB1 using FT-IR, NMR, ESI-mass, UV-Vis, and fluorescence spectroscopy.
• Evaluation of probe selectivity in aqueous-acetonitrile solutions with interfering species.
• Determination of detection limit (LoD) and binding constant (Kb) via spectral analysis.
• Validation of the binding mechanism using Job's plot, NMR, and DFT analyses.

Main Results:

• RSB1 demonstrated high selectivity for perchlorate (ClO4-) detection.
• The probe functioned as a
• turn-on
• luminescent sensor, showing enhanced emission at 363 nm.
• Achieved a low detection limit (LoD) of 0.121 μM and a binding constant (Kb) of 2.6 × 10^5 M^-1.
• Successfully detected perchlorate in real samples (tap water, distilled water, soil) with good recovery.

Conclusions:

• RSB1 is an effective "turn-on" luminescent probe for selective perchlorate detection.
• The probe's performance in real samples highlights its practical applicability.
• This work provides a valuable tool for monitoring perchlorate contamination.