A Mitochondria-Specific Fluorescent Probe for Visualizing Endogenous Hydrogen Cyanide Fluctuations in Neurons

Area of Science:

• Mitochondrial toxicology
• Cellular imaging
• Biochemical sensing

Background:

• Hydrogen cyanide (HCN) is a critical toxin with significant physiological and toxicological roles.
• Real-time visualization of HCN in mitochondria is essential for understanding its cellular functions.
• Existing methods lack the specificity and speed required for dynamic HCN monitoring.

Purpose of the Study:

• To develop a mitochondria-specific fluorescent probe for real-time, ratiometric imaging of HCN.
• To assess the probe's sensitivity, specificity, response time, and reversibility.
• To demonstrate the probe's utility in visualizing both exogenous and endogenous HCN in various cell types.

Main Methods:

• Synthesis of a novel coumarin pyrrolidinium-derived fluorescence probe (MRP1).
• Incorporation of a benzyl chloride subunit for enhanced mitochondrial retention.
• Application of the probe for ratiometric imaging of HCN in HepG2, PC12 cells, and neurons.

Main Results:

• The MRP1 probe enables specific, sensitive (LOD ~65.6 nM), and rapid (within 1s) detection of HCN.
• The probe exhibits reversible response and enhanced mitochondrial retention.
• Successful visualization of exogenous and endogenous HCN in cellular mitochondria, including detection of fluctuations.

Conclusions:

• The MRP1 probe provides a powerful tool for real-time, mitochondria-specific imaging of HCN.
• This advancement facilitates deeper insights into the toxicological and physiological impacts of HCN.
• The probe's capabilities extend to monitoring intracellular HCN generation and dynamics.