An Efficient Inclusion Complex Based Fluorescent Sensor for Mercury (II) and its Application in Live-Cell Imaging

Area of Science:

• Supramolecular Chemistry
• Analytical Chemistry
• Materials Science

Background:

• Cyclodextrins are widely used host molecules for forming inclusion complexes.
• Benzothiazole derivatives exhibit diverse photophysical properties.
• Developing selective and sensitive probes for heavy metal detection remains a significant challenge.

Purpose of the Study:

• To synthesize and characterize a novel inclusion complex between hydroxypropyl-β-cyclodextrin (H-CD) and 4-acetylphenyl-4-(((6-chlorobenzo[d]thiazol-2-yl)-imino)-methyl)-benzoate (L).
• To investigate the potential of this inclusion complex as a fluorescence probe for detecting heavy metal cations.
• To evaluate the performance of the probe for mercury ion (Hg2+) detection.

Main Methods:

• Solid-state characterization using FT-IR, 1H-NMR, XRD, FT-Raman, and SEM.
• Solution-state analysis via absorption and emission spectroscopy.
• Molecular docking simulations to understand binding interactions.
• Photoluminescence (PL) emission spectroscopy for cation sensing.

Main Results:

• The formation of the H-CD: L inclusion complex was confirmed through various spectroscopic and microscopic techniques.
• The inclusion complex exhibited selective and sensitive fluorescence enhancement in the presence of Hg2+.
• A linear detection range of 1 × 10-8 - 11 × 10-8 M and a limit of detection of 2.71 × 10-10 M were achieved for Hg2+.

Conclusions:

• The H-CD: L inclusion complex is a promising material for developing a solid-state fluorescence probe for Hg2+ detection.
• The probe demonstrates potential for application in real sample analysis and cell imaging.
• This study highlights the utility of cyclodextrin-based inclusion complexes in designing advanced sensing materials.