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Hybrimune Hybridoma Production System
Publication 015-1010191 Rev 4.0 • www.btxonline.com
The actual force applied is a complex formula, see Pohl, Chapter 4:
The larger the force the faster the cells will move. Although the equation is complex much can be learned by looking
at the terms in the equation.
r
c
is the radius of the cell
The equation shows that the force is proportional to the radius of the cell cubed. As a practical matter when the
radius of the cell gets below 3 or 4 micrometers the force falls below that of other forces and the process becomes
ineffective. Thus attempting to electrofuse bacteria is not a productive endeavor. This parameter is also of practical
interest when attempting to fuse a large cell with a smaller cell. The forces applied to the large cells are larger
causing them to move faster.
THE CELL RADIUS IS NOT UNDER USER CONTROL
e
medium
is the permittivity of the medium
Permittivity, also called electric permittivity (
e
), is a constant of proportionality that exists between electric
displacement and electric field intensity. This constant is equal to approximately 8.85 x 10
-12
farads per meter (F/m)
in free space (a vacuum). In other materials it can be much different, often substantially greater than the free-space
value, which is symbolized
e
o
. The medium used in electrofusion is close to high purity water which has
a permittivity of 80 x
e
o
. The permittivity of BTX Cytofusion medium used in the electrofusion process is about
78.5 x
e
o
. This term is constant over all conditions specified in this User Manual.
THE PERMITTIVITY IS NOT UNDER USER CONTROL
K
(
e, s, w,
r
)
This term is called the Clausius-Mossotti function. This function represents the time constants of the various ions,
medium in the cytoplasm, medium external to the cell, characteristics of the cell membrane and the cell radius.
The term w = 2
p
f where f is the frequency of the applied alignment waveform.
F
dep
=r
3
[2
p e
medium
K
(
e,s,w,
r
)]
∇
E
2
c
Cell Electrofusion Tutorial