Molecular dynamics insights into lipid bilayer electroporation under constant versus pulsed DC electric fields

Electroporation refers to the formation of pores in the membranes of cells or vesicles induced by an electric field. This technique is widely applied in gene therapy, drug delivery, cancer treatment, and molecular biology to enhance the uptake of nucleic acids, proteins, or drugs into cells by temporarily permeabilizing their membranes using an electric field. In this report, we have investigated pore dynamics in charged, neutral, and cholesterol-containing membranes under constant and pulsating direct current (DC) electric fields of 0.3 V/nm using molecular dynamics (MD) simulations, and we have presented a comparative analysis of the resulting pore behaviors. Under a constant DC electric field, pore opening occurred faster than pore closing. In contrast, under a pulsating DC field, the pore opening time was longer than the pore closing time. Additionally, the cholesterol-containing bilayer required a longer time to initiate pore formation compared to charged and neutral membrane systems. Moreover, the pulsating DC electric field-induced poration time was longer compared to the constant DC field-induced poration time for charged, neutral, and cholesterol-containing membranes. At the moment of pore formation, the solvent accessible surface area, the number of hydrogen bonds, dipole moment, and dielectric constant for all the models rapidly increased, which helped to elucidate precisely the pore dynamics. These findings might be helpful in design a more effective membrane-based electroporation techniques that have significant biotechnological and biomedical applications.