4-Azidocinnoline-Cinnoline-4-amine Pair as a New Fluorogenic and Fluorochromic Environment-Sensitive Probe

Area of Science:

• Chemical Biology
• Analytical Chemistry
• Biochemistry

Background:

• Development of novel fluorescent probes is crucial for sensitive biological detection.
• Environment-sensitive probes offer unique advantages for analyzing biological systems.

Purpose of the Study:

• To develop a new fluorogenic and fluorochromic probe based on azide-amine chemistry.
• To investigate the solvent-dependent fluorescence properties of the developed probe.
• To evaluate the probe's applicability in biological systems, specifically in cancer cell lines.

Main Methods:

• Synthesis of a novel fluorogenic probe: 4-azido-6-(4-cyanophenyl)cinnoline.
• Investigation of fluorescence properties in various solvents, focusing on polar media.
• Explanation of fluorescence mechanisms, including aggregation-induced emission (AIE) and excited state intermolecular proton transfer (ESPT).
• In vitro testing using HepG2 hepatic cancer cell line.
• Detection methods included fluorescent microscopy, flow cytometry, and HPLC analysis.

Main Results:

• A new fluorogenic and fluorochromic probe was successfully developed.
• The probe's fluorescence is strongly solvent-dependent, with enhanced emission in polar solvents like water.
• The probe exhibits environment-sensitive fluorescence in aqueous media due to AIE and ESPT mechanisms.
• Successful detection of azide-to-amine transformation within HepG2 cells was achieved.
• Demonstrated potential for analytical and biological applications in aqueous environments.

Conclusions:

• The developed azide-amine based probe is a promising tool for biological applications.
• Its environment-sensitive fluorescence in water opens avenues for advanced bioimaging and sensing.
• The probe's ability to function in aqueous media is advantageous for biological studies.