An Edaravone-Guided Design of a Rhodamine-Based Turn-on Fluorescent Probe for Detecting Hydroxyl Radicals in Living...

Area of Science:

• Biomedical Engineering
• Chemical Biology
• Molecular Imaging

Background:

• Hydroxyl radical (·OH), a reactive oxygen species (ROS), plays a role in biological processes but is challenging to detect due to its reactivity.
• Existing methods struggle with the specific detection of endogenous ·OH in complex biological environments.

Purpose of the Study:

• To develop a novel, highly sensitive, and selective fluorescent probe for detecting endogenous hydroxyl radicals (·OH).
• To utilize the probe for real-time imaging of ·OH in living cells and organisms.
• To explore the probe's potential in distinguishing cancer cells from normal cells based on ·OH levels.

Main Methods:

• Design and synthesis of a hybrid fluorescent probe, RH-EDA, integrating rhodamine and edaravone.
• Characterization of RH-EDA's fluorescence response to ·OH, including sensitivity and selectivity studies against other ROS.
• Application of RH-EDA for in vitro and in vivo imaging of endogenous ·OH in cells and zebrafishes, and for cancer cell discrimination.

Main Results:

• RH-EDA exhibits negligible fluorescence in physiological conditions but shows a significant (approx. 195-fold) fluorescence enhancement upon reaction with ·OH.
• The probe demonstrates high sensitivity and selectivity for ·OH, with no interference from other ROS.
• RH-EDA successfully visualized endogenous ·OH production in living cells and zebrafishes and differentiated cancer cells from normal cells.

Conclusions:

• RH-EDA is an effective fluorescent probe for specific and sensitive detection of hydroxyl radicals (·OH).
• The drug-guided probe design offers a promising strategy for developing new biosensors.
• RH-EDA facilitates imaging of ·OH-related biological processes and holds potential for cancer diagnostics.