Histidine based fluorescence sensor detects Hg2+ in solution, paper strips, and in cells

Area of Science:

• Analytical Chemistry
• Biomedical Engineering
• Environmental Science

Background:

• Mercury (Hg2+) is a toxic heavy metal pollutant with significant environmental and health impacts.
• Developing selective and sensitive detection methods for Hg2+ is crucial for monitoring and remediation.
• Existing detection methods often face challenges with selectivity, sensitivity, or practical application.

Purpose of the Study:

• To design and synthesize a novel chemosensor for the selective detection of mercury ions (Hg2+).
• To characterize the sensing mechanism and performance of the chemosensor.
• To demonstrate the practical application of the chemosensor in aqueous samples and biological imaging.

Main Methods:

• Synthesis of a bipodal thiocarbamate scaffold attached to histidine moieties as the chemosensor.
• Spectroscopic analysis (fluorescence) to study the binding interaction with Hg2+.
• Fabrication of paper-based sensors for visual detection.
• Application of the chemosensor for fluorescence imaging in adult zebrafish and HeLa S3 cells.

Main Results:

• The chemosensor exhibited remarkable selectivity for Hg2+.
• Hg2+ binding induced a 50 nm blue shift in fluorescence spectra and a 19-fold enhancement in fluorescence quantum yield.
• Visual detection of Hg2+ was achieved in solution and via paper strips in aqueous samples.
• Successful imaging of Hg2+ was demonstrated in adult zebrafish and human epithelial carcinoma HeLa S3 cells.

Conclusions:

• The developed chemosensor offers a highly selective and sensitive platform for Hg2+ detection.
• Its practical utility is demonstrated through visual detection on paper strips and biological imaging capabilities.
• This sensor holds potential for environmental monitoring and biomedical diagnostics of mercury contamination.