A rapid and selective phenothiazine-derived fluorescent probe for hypochlorous acid monitoring in living systems:...

Area of Science:

• Analytical Chemistry
• Biochemistry
• Chemical Biology

Background:

• Hypochlorous acid (HClO) is a reactive oxygen species (ROS) vital for immune defense and cell signaling.
• Elevated HClO levels are linked to inflammation, neurodegenerative diseases, and cancer.
• Accurate detection tools are crucial for understanding HClO's role and diagnosing diseases.

Purpose of the Study:

• To design and synthesize a novel small-molecule fluorescent probe for sensitive and selective detection of HClO.
• To evaluate the probe's performance in real-time biological imaging and biosensing applications.
• To investigate the probe's utility in visualizing inflammatory processes.

Main Methods:

• Synthesis of a novel fluorescent probe, (E)-3-(2-(10-ethyl-10H-phenothiazin-3-yl)vinyl)-1-methylquinoxalin-2(1H)-one), based on the ICT mechanism.
• Assessment of the probe's response time, selectivity, and sensitivity (limit of detection as low as 4 nM).
• In vitro cell experiments, zebrafish models, and mouse imaging to validate HClO detection and biosafety.

Main Results:

• The probe exhibits a rapid response (within 15 s), high selectivity, and a large Stokes shift (175 nm).
• Successful fluorescence imaging of HClO in cellular and zebrafish models with excellent biosafety.
• Demonstrated correlation between HClO levels and Systemic Inflammatory Response Syndrome (SIRS) in mouse models.

Conclusions:

• The developed fluorescent probe offers a powerful tool for real-time, sensitive, and selective detection of HClO in biological systems.
• The probe facilitates dynamic visualization of inflammatory processes like SIRS.
• Potential applications in bioanalysis, biosensing, and early diagnosis of inflammation-related diseases.