3D-printed fiber-bundle fluorescence microscope for quantifying single-cell responses to high-power radiofrequency...

Area of Science:

• Biophysics
• Electromagnetics
• Cell Biology

Background:

• Modern telecommunications utilize radiofrequency (RF) fields, necessitating safety standards based on adverse response thresholds.
• Real-time single-cell imaging under high-peak power RF exposure is challenging due to electronic damage and RF field interactions with metallic components.

Purpose of the Study:

• To develop a custom fluorescence microscopy system compatible with high-power RF environments.
• To enable real-time imaging of cellular responses to RF and microwave sources.

Main Methods:

• A custom, 3D-printed objective made of plastic and glass components was designed.
• A coherent fiber bundle was used to relay light between the RF exposure zone and the detection system.
• The system was validated against a commercial confocal microscope using nanosecond pulsed electric field (nsPEF) stimuli.

Main Results:

• The custom microscopy system demonstrated compatibility with high-power RF environments.
• Continuous fluorescence imaging and focal plane maintenance were achieved despite significant temperature variations (>40°C).
• The system operated effectively under 2.8 GHz free-field RF exposure.

Conclusions:

• The developed fluorescence microscopy system successfully enables real-time cellular imaging in high-power RF fields.
• This technology will advance research into the biological effects of RF and microwave exposure.
• The system's design overcomes critical experimental limitations in RF bioelectromagnetics research.