An isophorone-derived AIE-active probe for peroxynitrite detection and bioimaging applications

Area of Science:

• Chemical Sensing
• Materials Science
• Biophysical Chemistry

Background:

• Aggregation-induced emission (AIE) compounds offer unique photophysical properties due to restricted intramolecular rotation.
• Peroxynitrite (ONOO-) is a reactive nitrogen species implicated in various physiological and pathological processes.
• Developing selective and sensitive probes for ONOO- detection is crucial for biological research.

Purpose of the Study:

• To design and synthesize an isophorone-based probe (IHP) for peroxynitrite (ONOO-) detection.
• To investigate the aggregation behavior and photophysical properties of IHP.
• To evaluate the probe's performance for selective and sensitive ONOO- detection in vitro and in living cells.

Main Methods:

• Synthesis of an isophorone-based probe (IHP) utilizing a C=N reactive group.
• Photophysical studies in different solvent systems (DMSO:PBS and DMSO) to analyze aggregation behavior.
• Fluorescence spectroscopy to monitor the probe's response to peroxynitrite.
• Cell imaging experiments to visualize peroxynitrite in living cells.

Main Results:

• The probe IHP exhibits aggregation-induced emission (AIE) properties with red emission.
• IHP shows wavelength-dependent fluorescence changes in DMSO:PBS, indicating J-aggregation.
• The probe selectively reacts with peroxynitrite via oxidative cleavage of the C=N bond, causing a shift in emission.
• High sensitivity (detection limit 1.1 μM) and rapid response (<200 seconds) were achieved.
• Effective imaging of exogenous and endogenous peroxynitrite in living cells was demonstrated.

Conclusions:

• The developed isophorone-based probe (IHP) effectively utilizes AIE for sensitive and selective peroxynitrite detection.
• The probe's ability to image peroxynitrite in living cells opens avenues for biological and biomedical applications.
• This work highlights the potential of AIE probes in chemical sensing and biological imaging.