Cellular and Intravital ATP Imaging Using a Merocyanine-Hybrided Rhodamine Fluorescent Probe.

Area of Science:

• Biomedical Engineering
• Molecular Imaging
• Cellular Metabolism

Background:

• Real-time imaging of adenosine triphosphate (ATP) is crucial for understanding cellular energy metabolism and function.
• Existing molecular tools for intravital ATP imaging have limitations in sensitivity, response time, or tissue penetration.

Purpose of the Study:

• To design and characterize a novel fluorescent probe for sensitive and real-time intravital imaging of ATP.
• To evaluate the probe's utility in monitoring cellular ATP dynamics in various biological contexts, including cancer and ischemia/reperfusion.

Main Methods:

• Design and synthesis of a merocyanine-hybrided rhodamine fluorescent probe (PCR) with near-infrared properties.
• Characterization of the probe's photophysical properties, response kinetics, and affinity for ATP.
• Application of the probe for detecting exogenous and endogenous ATP, monitoring ATP fluctuations in cells and live mouse brain.

Main Results:

• The PCR probe exhibits near-infrared excitation/emission, rapid (<3 min) and reversible response, and deep tissue penetration (180 μm).
• The probe demonstrated a low detection limit (36.9 μM) and was successfully used to detect ATP generation in viable cells.
• Dynamic ATP fluctuations were monitored, revealing augmented ATP production in cancer cells and insights into β-lapachone-induced cancer cell death via energy crisis.

Conclusions:

• The developed PCR probe is a highly effective tool for real-time intravital ATP imaging, offering significant advantages over existing methods.
• The probe facilitates the elucidation of ATP's role in complex biological processes, including cancer metabolism and cerebral ischemia/reperfusion.
• This imaging capability holds potential for advancing our understanding of energy metabolism in various diseases and biological environments.