Changes in the permeation characteristics of ROS through biological membranes by discharge plasma-Induced electric field

  In plasma medicine, the oxidation reaction of active species in vivo (biostimulation) is known to be an important factor. However, the actual cell penetration mechanism is complex, and electronic behaviors such as surface charging and membrane potential change are likely to contribute. Therefore, the purpose of this study is to clarify the basic mechanisms of plasma medicine by focusing on the interaction with cells through the supply of electric field and charge, apart from the chemical reactions of reactive species that have been studied.

  In this paper, the free energy and permeability coefficients of the cell membrane to plasma-induced reactive species when the electric field is varied are numerically analyzed by molecular dynamics (MD). The cell membrane model was constructed with a lipid bilayer consisting of 128 POPC phospholipids and a 0.15 M KCl solution. Hydrogen peroxide () was used as the active species. The electric field was varied from 0 to 0.4 V/nm.

  The free energy at the center of the membrane was reduced by about 40% at the maximum by the application of the electric field, and the permeability of the membrane increased sharply by a factor of about 8 from 0.3 to 0.4 V/nm. The influence of electric field directions on those properties was also discussed.