Role of pulse shape in cell membrane electropermeabilization.

Area of Science:

• Biophysics
• Cell Biology
• Electroporation

Background:

• Cell membrane electropermeabilization is crucial for molecular delivery.
• Previous studies explored various electric pulse shapes for improved efficiency.
• Unipolar rectangular pulses are commonly used but may be suboptimal.

Purpose of the Study:

• To systematically investigate the role of electric pulse shape in cell membrane permeabilization.
• To compare the efficiency of different pulse waveforms (unipolar, bipolar, sine-modulated) on cell permeabilization, death, and molecular uptake.
• To elucidate the underlying principles governing electroporation efficiency based on pulse characteristics.

Main Methods:

• Comparison of 1-ms unipolar pulses with varying rise/fall times (2-100 µs).
• Evaluation of triangular, sine, and rectangular bipolar pulses.
• Assessment of sine-modulated unipolar pulses with varying modulation percentages.
• Analysis of cell death and molecular uptake as efficacy indicators.

Main Results:

• No significant difference in efficiency was observed for unipolar pulses with varying rise/fall times.
• Bipolar and sine-modulated pulse shapes showed varying efficiencies compared to unipolar pulses.
• Experimental results are explainable by the time the pulse amplitude exceeds a critical value.

Conclusions:

• The duration of supra-critical pulse amplitude is the primary determinant of electroporation efficiency.
• Pulse shape modifications can influence cell membrane permeabilization, cell death, and molecular uptake.
• Understanding the role of pulse amplitude duration optimizes electroporation protocols.