"Reactive" probe for hydrogen sulfite: "turn-on" fluorescent sensing and bioimaging application

Area of Science:

• Analytical Chemistry
• Biochemistry
• Chemical Sensing

Background:

• Hydrogen sulfite (HSO3-) is an important biological molecule.
• Developing selective and sensitive detection methods for HSO3- is crucial for biological and chemical research.

Purpose of the Study:

• To synthesize a novel "switching-on" fluorescent probe for hydrogen sulfite detection.
• To investigate the probe's sensing mechanism, sensitivity, selectivity, and application in biological samples.

Main Methods:

• Synthesis of a fluorescent probe (C1) utilizing intramolecular charge transfer (ICT).
• Spectroscopic analysis to evaluate the probe's response to hydrogen sulfite ions.
• Determination of detection limit and selectivity against common anions.
• Cellular imaging experiments in HeLa cells.

Main Results:

• The probe C1 exhibited a "turn-on" fluorescence response upon addition of HSO3- ions, changing from non-emission to strong green fluorescence.
• High sensitivity was achieved, with a detection limit as low as 3.0 μM.
• The probe demonstrated excellent selectivity for HSO3- over other common anions.
• Successful application of C1 for detecting hydrogen sulfite in HeLa cells using turn-on fluorescence.

Conclusions:

• A novel, highly sensitive, and selective fluorescent probe (C1) for hydrogen sulfite detection was successfully developed.
• The probe's ICT mechanism and "turn-on" fluorescence provide a reliable method for HSO3- sensing.
• C1 holds promise for real-time monitoring of hydrogen sulfite in biological systems.