A BODIPY-derived fluorescent probe for cellular pH measurements.

Area of Science:

• * Biochemistry and Molecular Biology
• * Cell Biology
• * Chemical Biology

Background:

• * Accurate monitoring of intracellular pH is crucial for understanding cellular processes.
• * Existing fluorescent probes often lack specificity or long-term stability for cytosolic pH.
• * BODIPY-derived compounds offer unique photophysical properties for sensing applications.

Purpose of the Study:

• * To develop and characterize a novel BODIPY-appended calix[4]arene as a fluorescent probe for intracellular pH.
• * To evaluate the probe's cell permeability, retention, and cytotoxicity.
• * To assess the probe's ability to detect pH fluctuations during early stages of cell apoptosis.

Main Methods:

• * Synthesis and characterization of the BODIPY-appended calix[4]arene probe.
• * In vitro assessment of probe's photophysical properties and pH sensitivity.
• * Cellular imaging studies to evaluate cell permeability, retention, and cytotoxicity.
• * Induction of apoptosis using hydrogen peroxide and monitoring of pH changes via fluorescence.

Main Results:

• * The BODIPY-calix[4]arene probe demonstrated excellent cell permeability and high retention within cells for 24 hours.
• * The probe exhibited minimal cytotoxicity, ensuring reliable long-term cellular observation.
• * Significant fluorescence changes were observed, correlating with pH fluctuations during early apoptosis induced by hydrogen peroxide.
• * This represents the first reported BODIPY-derived probe for monitoring cytosolic pH.

Conclusions:

• * BODIPY-appended calix[4]arene is a highly effective and stable fluorescent probe for intracellular pH.
• * The probe facilitates precise observation of minor pH changes near neutrality within cells.
• * This tool is valuable for studying cellular events such as apoptosis, offering new insights into early-stage mechanisms.