Electrical field and current distributions in electrochemotherapy

Brandisky, Kostadin; Daskalov, И.

doi:10.1016/s0302-4598(98)00232-3

Cited by 18 publications

(14 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One of the major problems with respect to conductivity measurements in vivo is the inhomogeneous distribution of current density and electric field due to inhomogeneous and anisotropic properties of the tissue. For successful tissue electroporation, anatomically based mathematical models are important tools for prediction of the outcome of the treatment Brandinsky and Daskalov 1999;Miklavčič et al 2000;Šel et al 2007;Miklavčič et al 2006a).…”

Section: From Single-cell To Tissuementioning

confidence: 99%

Electroporation in Biological Cell and Tissue: An Overview

Kandušer

Miklavčič²

2008

Electrotechnologies for Extraction From Food Plants and Biomaterials

View full text Add to dashboard Cite

In this chapter, basics and mechanisms of electroporation are presented. Most important electric pulse parameters for electroporation efficiency for different applications that involve introduction of small molecules and macromolecules into the cell or cell membrane electrofusion are described. In all these applications, cell viability has to be preserved. However, in some biotechnological applications, such as liquid food sterilization or water treatment, electroporation is used as a method for efficient cell killing. For all the applications mentioned above, besides electric pulse parameters, other factors, such as electroporation medium composition and osmotic pressure, play significant roles in electroporation effectiveness. For controlled use of the method in all applications, the basic mechanisms of electroporation need to be known. The phenomenon was studied from the single-cell level and dense cell suspension that represents a simplified homogenous tissue model, to complex biological tissues. In the latter, different cell types and electric conductivity that change during the course of electric pulse application can significantly affect the effectiveness of the treatment. For such a complex situation, the design and use of suitable electrodes and theoretical modeling of electric field distribution within the tissue are essential. Electroporation as a universal method applicable to different cell types is used for different purposes. In medicine it is used for electrochemotherapy and genetherapy. In biotechnology it is used for water and liquid food sterilization and for transfection of bacteria, yeast, plant protoplast, and intact plant tissue. Understanding the phenomenon of electroporation, its mechanisms and optimization of all the parameters that affect electroporation is a prerequisite for successful treatment. In addition to the parameters mentioned above, different biological characteristics of treated cell affect the outcome of the treatment. Electroporation, gene electrotransfer and electrofusion are affected by cell membrane fluidity, cytoskeleton, and the presence of the cell wall in bacteria yeast and plant cells. Thus, electroporation parameters need to be specifically optimized for different cell types.

show abstract

Section: From Single-cell To Tissuementioning

confidence: 99%

Electroporation in Biological Cell and Tissue: An Overview

Kandušer

Miklavčič²

2008

Electrotechnologies for Extraction From Food Plants and Biomaterials

View full text Add to dashboard Cite

show abstract

“…Besides effective conductivity the key parameter of permeabilization on a tissue level is the local electric field intensity. As the field results from a voltage applied between the electrodes, the electrode configuration influences the field distribution in tissue [17]- [19]. Electrode configurations used for tissue permeabilization are parallel plates, wire and contact plate electrodes as well as needle electrodes and needle arrays [19]- [21].…”

Section: Sequential Finite Element Model Of Tissue Electropermeabilizmentioning

confidence: 99%

Sequential Finite Element Model of Tissue Electropermeabilization

Šel

Cukjati

Batiuškaitė

et al. 2005

IEEE Trans. Biomed. Eng.

244

188

View full text Add to dashboard Cite

Abstract-Permeabilization, when observed on a tissue level, is a dynamic process resulting from changes in membrane permeability when exposing biological cells to external electric field (E).In this paper we present a sequential finite element model of E distribution in tissue which considers local changes in tissue conductivity due to permeabilization. These changes affect the pattern of the field distribution during the high voltage pulse application.The presented model consists of a sequence of static models (steps), which describe E distribution at discrete time intervals during tissue permeabilization and in this way present the dynamics of electropermeabilization. The tissue conductivity for each static model in a sequence is determined based on E distribution from the previous step by considering a sigmoid dependency between specific conductivity and E intensity. Such a dependency was determined by parameter estimation on a set of current measurements, obtained by in vivo experiments. Another set of measurements was used for model validation. All experiments were performed on rabbit liver tissue with inserted needle electrodes. Model validation was carried out in four different ways: 1) by comparing reversibly permeabilized tissue computed by the model and the reversibly permeabilized area of tissue as obtained in the experiments; 2) by comparing the area of irreversibly permeabilized tissue computed by the model and the area where tissue necrosis was observed in experiments; 3) through the comparison of total current at the end of pulse and computed current in the last step of sequential electropermeabilization model; 4) by comparing total current during the first pulse and current computed in consecutive steps of a modeling sequence.The presented permeabilization model presents the first approach of describing the course of permeabilization on tissue level. Despite some approximations (ohmic tissue behavior) the model can predict the permeabilized volume of tissue, when exposed to electrical treatment. Therefore, the most important contribution and novelty of the model is its potentiality to be used as a tool for determining parameters for effective tissue permeabilization.

show abstract

“…Validated by experiments, they allow prediction of the outcome of pulse application and help in choosing the most efficient protocols and pulse parameters for specific applications. This approach also facilitates development and optimization of electrodes and their placement with respect to target tissue and can be of great help in treatment planning Brandisky and Daskalov, 1999;Miklavcic et al, 2000;Dev et al, 2003;Miklavcic et al, 2006a;Sel et al, 2007;Corovic et al, 2008;Zupanic et al, 2008). A good model verified with experimental results is a powerful tool and offers useful insight into the understanding of processes modeled.…”

Section: Introductionmentioning

confidence: 95%