Figure 24: Two Needles Per Row Field - BTX AgilePulse ID User Manual

AgilePulse ™
Electrode
Electrodes used in ex vivo and in vivo electroporation are quite
different. In ex vivo electroporation, the cells are generally placed in
an aqueous ionic medium in a chamber that has parallel plate metal
electrodes. This configuration produces very uniform electric fields.
For in vivo electroporation the electric fields must be established
on a tissue in the body. In this configuration parallel plates are not
practical for vaccine delivery.
For in vivo use two parallel rows of needles are used. This
configuration was first published in an abstract form by Dr. Julie
Gehl in 1997 (Herlev Hospital, Denmark).
Parallel row arrays must be carefully designed to produce electric
field intensities as close to uniform as possible to ensure as
many cells as possible are exposed to the same field. The key
parameters are:
• Number of needles in each row
• Diameter of the needles
• Spacing of the needles in the row
• Space between the two rows
In general the more needles per row and the greater the spacing
between the rows, the closer the electric field approaches that of
a parallel plate. As an example, the calculated electric field for two
needles per row is presented below:
4 mm

Figure 24: Two Needles per Row Field

As the spacing between the rows increases the electric field rapidly
falls off and cold spots form pores in the cells and transfectant
delivery does not occur.
The AgilePulse needle electrodes are specifically designed to
produce near uniform electric fields in the treatment volume.
21
ID Tutorial
6 mm
AgilePulse ID In Vivo Gene Delivery System
Publication 015-101444 Rev 2.0 • www.btxonline.com