Temperature sensing using fluorescent nanothermometers.

Area of Science:

• Nanotechnology
• Biophysics
• Cell Biology

Background:

• Measuring intracellular temperature is crucial for understanding cellular processes but technically challenging.
• Existing methods lack the precision and non-invasiveness required for single-cell analysis.
• Temperature fluctuations play a significant role in cell function and death.

Purpose of the Study:

• To develop and validate a novel nanothermometer for precise temperature measurements in solutions and living cells.
• To investigate the thermal profiles of HeLa cancer cells using the developed nanothermometer.
• To demonstrate the capability of nanothermometers in monitoring thermally induced cell death.

Main Methods:

• Fabrication of NaYF(4):Er(3+),Yb(3+) nanoparticles exhibiting temperature-sensitive fluorescence.
• Utilizing the intensity ratio of specific Er(3+) fluorescence bands to determine temperature.
• Employing pump-probe experiments to analyze thermal profiles in colloidal solutions.
• Incubating nanoparticles with HeLa cells and measuring intracellular temperatures via fluorescence.

Main Results:

• The nanothermometer demonstrated accurate temperature determination in aqueous solutions.
• Successful uptake of nanoparticles by HeLa cervical cancer cells was achieved.
• Intracellular temperatures of HeLa cells were monitored in real-time from 25°C to 45°C.
• The nanothermometer effectively captured temperature changes leading to thermally induced cell death.

Conclusions:

• The developed NaYF(4):Er(3+),Yb(3+) nanothermometer provides a novel and accurate method for intracellular thermometry.
• This technology enables detailed study of thermal dynamics within living cells, including responses to thermal stress.
• The nanothermometer holds potential for applications in cancer research and understanding thermal effects on cellular processes.