Ratiometric fluorimetric and colorimetric probe for sensing and imaging pH changes in living cells

Area of Science:

• Biochemistry
• Cell Biology
• Analytical Chemistry

Background:

• Intracellular pH is critical for cell, enzyme, and tissue activity.
• Monitoring intracellular pH is vital for understanding cellular metabolism and disease progression.

Purpose of the Study:

• To synthesize and characterize a novel hemicyanine-based probe (HTBI) for intracellular pH detection.
• To evaluate the probe's performance, including sensitivity, selectivity, photostability, and cytotoxicity.

Main Methods:

• Synthesis of a hemicyanine-based probe (HTBI).
• Spectroscopic analysis of probe response to pH changes (colorimetric and fluorometric).
• Evaluation of probe characteristics: pKa, sensitivity, selectivity, photostability, reversibility, and cytotoxicity.

Main Results:

• The HTBI probe showed a distinct color change (yellow to amaranth) and spectral red shift with increasing pH.
• The probe exhibited ratiometric fluorescence emission with a pKa of 8.82.
• HTBI demonstrated high sensitivity, selectivity, good photostability, reversibility, and low cytotoxicity.

Conclusions:

• The synthesized HTBI probe is a highly effective tool for ratiometric fluorescence detection of intracellular pH.
• HTBI's properties make it suitable for real-time monitoring of physiological and pathological pH changes in cells.