A protein-dye hybrid system as a narrow range tunable intracellular pH sensor

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Cell Biology

Background:

• Accurate intracellular pH monitoring is crucial for early disease diagnosis, particularly for cancers.
• Existing pH sensors face challenges in creating custom arrays for narrow biological pH ranges.
• Developing easily constructible sensors for minute pH variations remains a significant challenge.

Purpose of the Study:

• To develop novel two-component hybrid sensors for precise monitoring of intracellular pH variations.
• To create custom-made pH sensor arrays with tunable sensitivity for narrow biological pH windows.
• To demonstrate the application of these sensors in monitoring pH changes within HeLa cells.

Main Methods:

• Fabrication of hybrid sensors using protein and organic dye nanoparticles.
• Tuning sensor sensitivity by adjusting the ratio of protein and dye components.
• Utilizing fluorescence imaging to monitor pH variations in biological systems, specifically HeLa cells.

Main Results:

• The hybrid sensors exhibit tunable sensitivity, allowing for customization across different pH windows.
• The dye interacts with the protein via non-covalent and covalent bonds at different pH levels.
• Two distinct fluorescent signals at 700 nm and 480 nm are triggered, correlating with pH changes.
• Successful monitoring of pH variations in HeLa cells using fluorescence imaging.

Conclusions:

• The developed protein-dye hybrid sensors offer a novel approach for creating custom-made, narrow-range tunable pH sensors.
• These sensors provide a sensitive and adaptable tool for monitoring intracellular pH, with potential applications in disease diagnosis.
• The fluorescence imaging technique enables effective visualization and quantification of pH changes in cellular environments.