A novel tryptanthrin-based "on-off-on" probe for sequential sensing Cu²⁺/S^2- in water samples

Area of Science:

• Analytical Chemistry
• Environmental Science
• Materials Science

Background:

• Copper ions (Cu²⁺) and sulfide (S^2-) are crucial in biological and pathological processes.
• Development of selective and sensitive probes for these analytes is essential for monitoring and research.

Purpose of the Study:

• To design and synthesize a novel tryptanthrin-based fluorescent probe (TR-1) for detecting Cu²⁺ and S^2-.
• To evaluate the probe's selectivity, sensitivity, and potential application in environmental water samples.

Main Methods:

• Facile and economical synthesis of the tryptanthrin-based probe TR-1.
• Spectroscopic analysis to determine the probe's response to various metal ions, including Cu²⁺.
• Investigation of the TR-1-Cu²⁺ complex for subsequent S^2- detection.

Main Results:

• TR-1 demonstrated high selectivity and sensitivity for Cu²⁺ detection, with a detection limit of 24 nM, surpassing the Chinese standard for fishery water quality.
• The TR-1-Cu²⁺ complex effectively detected S^2- with a detection limit of 62 nM.
• The probe showed potential for practical application in analyzing copper ions in real water samples.

Conclusions:

• The developed TR-1 probe offers a selective, sensitive, and cost-effective method for detecting both Cu²⁺ and S^2-.
• TR-1 holds promise for environmental monitoring, particularly for assessing copper ion levels in water bodies.
• This research contributes a valuable tool for the detection of key ions in physiological and environmental contexts.