Sensitive fluorescent chemosensor for Hg(II) in aqueous solution using 4'-dimethylaminochalcone

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Materials Science

Background:

• Mercury (Hg) poses significant neurotoxicity risks.
• Fluorescent probes are crucial for visualizing cellular processes.
• Chalcone derivatives offer underexplored fluorescent properties.

Purpose of the Study:

• To synthesize and characterize a novel chalcone derivative as a fluorescent chemosensor.
• To evaluate the chemosensor's selectivity and sensitivity towards mercury ions (Hg(II)).
• To elucidate the interaction mechanism between the chalcone and Hg(II) using computational methods.

Main Methods:

• Synthesis of chalcone (2E)-3-(4-(dimethylamino)phenyl)-1-phenylprop-2-en-1-one.
• Photophysical property assessment.
• Fluorescence quenching studies in aqueous media with Hg(II).
• Determination of limit of detection (LOD) and limit of quantification (LOQ).
• Application of Benesi-Hildebrand and Stern-Volmer equations.
• Computational modeling of the chalcone-Hg(II) interaction.

Main Results:

• The synthesized chalcone exhibits selective fluorescence quenching in the presence of Hg(II).
• Key performance metrics include LOD = 136 nM and LOQ = 454 nM with a 1:1 stoichiometry.
• Association constant (K_a) and fluorescence quenching constant (K_SV) were determined.
• Computational analysis suggests a photoinduced electron transfer (PET) blocking mechanism.

Conclusions:

• The developed chalcone-based molecule serves as an effective fluorescent chemosensor for Hg(II).
• The sensor's high sensitivity and selectivity are suitable for detecting mercury contamination.
• Understanding the quenching mechanism aids in designing advanced fluorescent probes.