Simulation of Cold Atmospheric Plasma Generated by Floating-Electrode Dielectric Barrier Pulsed Discharge Used for the Cancer Cell Necrosis

Samira Elaissi,Kamel Charrada

doi:10.3390/coatings11111405

Abstract

A numerical simulation of a pulsed floating electrode dielectric barrier discharge (FE-DBD) at atmospheric pressure, used for melanoma cancer cell therapy, is performed using a plasma model in COMSOL Multiphysics software. Distributions of electron density, space charge, and electric field are presented at different instants of the pulsed argon discharge. Significant results related to the characteristics of the plasma device used, the inter-electrodes distance, and the power supply are obtained to improve the efficiency of FE-DBD apparatus for melanoma cancer cell treatment. The FE-DBD presents a higher sensitivity to short pulse durations, related to the accumulated charge over the dielectric barrier around the powered electrode. At higher applied voltage, more energy is injected into the discharge channel and an increase in electron density and electric consumed power is noted. Anticancer activity provided by the FE-DBD plasma is improved using a small interelectrode distance with a high electron emission coefficient and a high dielectric constant with a small dielectric thickness, allowing higher electron density, generating reactive species responsible for the apoptosis of tumor cells.

Highlights

In the past decades, cold plasma discharge generated at atmospheric pressure has received an increasing amount of attention due to the outstanding quality it offers and the vast range of applications in the medical field, such as bio-sterilization, skin regeneration, wound healing, teeth bleaching, blood coagulation, and engineering of biomaterial and tissues [1,2,3,4]
A second current peak of negative polarity is observed at the end of the pulse, which indicates that a second discharge occurs in the reactor due to th2e.0accumulation of charged species on the dielec1t0ric during the first discharge.ApFpliued rvotlthageermore, the high-frequency induction current genera8ted in gas plasma can be Anodic current divided into tw1o.5 components
-8 peak of negative polarity is observed at the end of the pulse, which indicates that a second di-s10c0h.0arg0e.2 oc0c.4urs0.i6n th0.e8 re1a.0cto1r.2du1e.4to 1t.h6 e a1c.8cu2m.0u-2.l0ation of charged species on the dielectric during the first dischaTrimgee.(mFsu) rthermore, the high-frequency induction current generated in gas plasma can be divided into two components

Summary

Introduction

Cold plasma discharge generated at atmospheric pressure has received an increasing amount of attention due to the outstanding quality it offers and the vast range of applications in the medical field, such as bio-sterilization, skin regeneration, wound healing, teeth bleaching, blood coagulation, and engineering of biomaterial and tissues [1,2,3,4]. Most biomedical devices using cold plasma discharge implement dielectric barrier discharge (DBD) to provide a higher intensity and more adaptable and controlled discharge [8,9,10,11]. The floating electrode dielectric barrier discharge (FE-DBD) presents a novel approach specially developed for biomedical applications, with a high practical potential for cancer cell treatment [12]. In this configuration, FE-DBD devices do not contain a grounded electrode, which is replaced by affected living tissue or organ and, technically, a sustained discharge is activated between a covered dielectric driven electrode and a specimen surface applied with a floating (free) potential. The distance between the working electrode and the surface being treated is approximately 3 mm, depending upon the form, polarity, and the applied voltage signal period

Results

Discussion

Conclusion