Electroporation of cell membrane visualized under a pulsed-laser fluorescence microscope

Area of Science:

• Biophysics
• Cell Biology
• Membrane Science

Background:

• Controlled cell membrane permeability is crucial for various biological and biotechnological applications.
• Electroporation, the use of electric pulses to permeabilize membranes, is a key technique.
• Understanding the dynamics of electroporation at the single-cell level is essential for optimizing its use.

Purpose of the Study:

• To investigate the temporal and spatial dynamics of cell membrane events during microsecond electroporation.
• To quantify membrane conductance changes and area loss during and after electric pulse exposure.
• To elucidate the resealing process of the cell membrane post-electroporation.

Main Methods:

• Development of a submicrosecond time-resolution fluorescence microimaging system.
• Application of microsecond electric pulses to single cells.
• Real-time monitoring of membrane conductance and structural changes.

Main Results:

• Observed significant membrane conductance increase, indicating pore formation, in regions exceeding a critical transmembrane potential.
• Quantified membrane area loss between 0.01-0.1% during electroporation.
• Documented a rapid decrease in conductance to a low level within a submillisecond after the pulse, signifying partial membrane resealing.

Conclusions:

• Microsecond electric pulses induce transient, localized membrane permeabilization.
• The cell membrane exhibits partial recovery (resealing) following electroporation.
• This study provides high-resolution insights into the biophysical mechanisms of electroporation.