Triazine based fluorescent sensor for sequential detection of Hg

Area of Science:

• Analytical Chemistry
• Materials Science
• Organic Chemistry

Background:

• Mercury ions (Hg2+) and L-cysteine (Cys) are crucial analytes in biological and environmental monitoring.
• Developing selective and sensitive fluorescent sensors for sequential detection is highly desirable.

Purpose of the Study:

• To design and synthesize a triazine-based fluorescent sensor (TBT) for the sequential detection of Hg2+ and L-cysteine.
• To investigate the sensing mechanism and evaluate the sensor's performance in real samples.

Main Methods:

• Rational design and synthesis of the triazine-based fluorescent sensor TBT.
• Fluorescence spectroscopy for detecting Hg2+ and L-cysteine.
• 1H NMR titration and Density Functional Theory (DFT) studies to elucidate interaction mechanisms.

Main Results:

• Sensor TBT exhibited selective and sensitive fluorescence enhancement upon binding with Hg2+ via CHEF and ICT mechanisms.
• The TBT-Hg2+ complex allowed for subsequent selective fluorescence quenching detection of L-cysteine.
• A low limit of detection (61.9 nM) for Hg2+ was achieved, and the sensor performed well in real samples.
• DFT studies confirmed non-covalent interactions between the sensor and analytes.

Conclusions:

• The developed TBT sensor provides an effective platform for the sequential and selective detection of Hg2+ and L-cysteine.
• The sensor's performance in real samples and the insights from DFT studies highlight its potential for practical applications.
• The sequential detection strategy enabled the fabrication of a logic gate.