An experimental evaluation of the critical potential difference inducing cell membrane electropermeabilization

Area of Science:

• Biophysics
• Cell Biology
• Electrochemistry

Background:

• Electric field pulses induce cell membrane permeabilization (electropermeabilization) and fusion (electrofusion).
• These cellular responses are triggered by modulating the membrane potential difference.
• The vectorial nature of electric fields causes position-dependent modulation of the membrane potential on the cell surface.

Purpose of the Study:

• To investigate the position-dependent effects of electric fields on cell membranes.
• To determine the critical membrane potential difference required for electropermeabilization.
• To reconcile the difference between experimentally observed critical field strengths for permeabilization and fusion.

Main Methods:

• Applying electric field pulses to intact cell suspensions.
• Measuring and calculating the critical membrane potential difference for electropermeabilization.
• Comparing results across different cell systems and with previous studies on lipid vesicles.

Main Results:

• The critical membrane potential difference for electropermeabilization was found to be approximately 200 mV for various cell systems.
• This value is significantly lower than previously assumed in many studies.
• The position-dependent modulation of membrane potential explains differences in critical field strengths for permeabilization and fusion.

Conclusions:

• The critical membrane potential difference for inducing cell membrane permeabilization is consistently around 200 mV.
• This finding challenges previous assumptions and provides a unified understanding of electropermeabilization and electrofusion.
• Understanding this critical threshold is crucial for optimizing electro-based cell manipulation techniques.