Mathematical Models of Mass Transfer in Tissue for Molecular Medicine Reversible Electroporation - Porous Media: Applications in Biological Systems and Biotechnology - page 68

2.7 Future Research Needs in Mathematical Modeling
of the Field of Electroporation
As reversible electroporation gains momentum as a clinical method for in vivo
application the need for mathematical models is expected to rise. The com-
bination of increasingly accurate models that are expected to improve, for
instance, as molecular dynamics simulations (Tarek 2005) become more avail-
able together with real time monitoring techniques such as the one presented
in this chapter will probably aid in understanding the nature of the electropo-
ration process. Several issues still remain as a topic of active scientific research
both on the academic level and for developing practical clinical tools.
Today, electroporation research, and particularly those studies that use
conductivity measurements to monitor the process, is conducted mostly using
one of three approaches:

1. Electroporation of membranes—usually artificial membranes that

are grown specifically for this purpose in a chamber specifically
designed for these experiments.

2. Electroporation of cells in suspension— in vitro procedure where

cells are suspended in some medium and usually placed in an elec-
troporation cuvette.

3. Electroporation of tissue—usually an in vivo procedure where either

needle electrodes are inserted into the tissue or plate electrodes are
placed on both sides of a treated tissue.

Every one of these methods has some benefits and some disadvantages. The
most controlled environment is when electroporation of artificial membranes is
performed. But, although electroporation can be observed in artificial bilayers,
it does not always reveal the same characteristics as cell membranes, which
by themselves also demonstrate a variety of behaviors.
The electroporation of cells in suspensions is also very important, and
although it is somewhat less controlled than the electroporation of the mem-
brane by itself, it is more closely related to in vivo electroporation. It also
has many practical applications as a method, for example, for introducing
genes into cells or producing knockout mice. Measuring the conductivity of
the suspension is not a simple procedure, and results may vary significantly
depending on the type and concentration of the medium for instance.
Conducting in vivo electroporation experiments is obviously the most
direct approach to study this procedure. Nevertheless, nonuniform fields that
are created by needle electrodes and to some extent by plate electrodes as well,
combined with tissue inhomogeneities create a very complex environment for
analysis. If the EIT technique matures into a reliable tool for monitoring elec-
troporation, it may be used very eciently for further research into the effects
of in vivo electroporation, both in the reversible and irreversible modes.