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Electromagnetic Fields in Biological Systems
1.8
1.6
5 kV/cm
280 ns
40 ns
40 ns
1.4
Membrane potential (V)
1.2
1.0
0.8
0.6
0.4
0.2
0.0 0
50
100
150
200
250
300

Time (ns)

(a)

1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
25 kV/cm
1.75 ns
1.75 ns
11 ns
0
2
4
6
8
10
12
Time (ns)
Membrane potential (V)
(b)
Figure 2.3 (a) Membrane voltage across plasma membrane (solid line) and inner (mitochondrial) membrane (dotted line) for a 300-ns trapezoidal pulse. (b) The same for an 11-ns long pulse.
The thickness of the inner membrane was assumed to be half of that of the plasma membrane. (From
Joshi, R. P., Q. Hu, K. H. Schoenbach, and S. J. Beebe. 2004. Phys Rev E 69:051901. With permission.)
example, transmembrane voltages (Kotnik and Miclavcic 2006) are shown in Figure 2.4.
Here, the conductivity of the organelle interior was assumed to be higher than that of
the cytosol and the membrane permittivity lower than that of the plasma membrane.
A similar result also emerged if the organelle membrane had lower dielectric permittivities than the cellular membrane.