Development of a Rapid-Response Fluorescent Probe for H₂S: Mechanism Elucidation and Biological Applications

Area of Science:

• Chemical Biology
• Analytical Chemistry
• Biochemistry

Background:

• Hydrogen sulfide (H2S) is a crucial signaling molecule in physiological and pathological processes.
• Accurate detection of H2S in biological systems is essential for understanding its roles.
• Existing detection methods may lack sensitivity or selectivity.

Purpose of the Study:

• To develop novel fluorescent probes for sensitive and selective H2S detection.
• To evaluate the performance of these probes in aqueous media and biological samples.
• To investigate the mechanism of H2S detection by the developed probes.

Main Methods:

• Synthesis of two 1,8-naphthalimide-based fluorescent probes (M1 and M2).
• H2S detection assays in aqueous solutions and cell imaging studies.
• Characterization using fluorescence spectroscopy, reaction kinetics, and 1H NMR titration.

Main Results:

• M1 demonstrated high sensitivity (0.64 µM detection limit) and selectivity for H2S.
• M1 exhibited a rapid response and effectiveness in the pH range of 6-10.
• Mechanism studies confirmed H2S-triggered nucleophilic substitution, and M1 was successfully applied in cell imaging.
• M2 showed weaker performance due to lower sensitivity, stability, and solubility.

Conclusions:

• M1 is a highly effective and selective fluorescent probe for H2S detection.
• M1 is suitable for detecting H2S in biological environments, including cell imaging.
• This probe offers a valuable tool for studying the biological functions of H2S in health and disease.