The change in the membrane potential of Jurkat cells in response to nanosecond pulsed electric fields was studied for pulses with a duration of 60 ns and maximum field strengths of similar to 100 kV/cm (100 V/cell diameter). Membranes of Jurkat cells were stained with a fast voltage-sensitive dye, ANNINE-6, which has a subnanosecond voltage response time. A temporal resolution of 5 ns was achieved by the excitation of this dye with a tunable laser pulse. The laser pulse was synchronized with the applied electric field to record images at times before, during, and after exposure. When exposing the Jurkat cells to a pulse, the voltage across the membrane at the anodic pole of the cell reached values of 1.6 V after 15 ns, almost twice the voltage level generally required for electroporation. Voltages across the membrane on the side facing the cathode reached values of only 0.6 V in the same time period, indicating a strong asymmetry in conduction mechanisms in the membranes of the two opposite cell hemispheres. This small voltage drop of 0.6 - 1.6 V across the plasma membrane demonstrates that nearly the entire imposed electric field of 10 V/μm m penetrates into the interior of the cell and every organelle.
Original Publication Citation
Frey, W., White, J. A., Price, R. O., Blackmore, P. F., Joshi, R. P., Nuccitelli, R., . . . Kolb, J. F. (2006). Plasma membrane voltage changes during nanosecond pulsed electric field exposure. Biophysical Journal, 90(10), 3608-3615. doi:10.1529/biophysj.105.072777
Frey, W.; Price, R. O.; Blackmore, P. F.; Joshi, R. P.; Nuccitelli, R.; Beebe, S. J.; Schoenbach, K. H.; and Kolb, J. F., "Plasma Membrane Voltage Changes During Nanosecond Pulsed Electric Field Exposure" (2006). Bioelectrics Publications. 192.
0000-0002-6075-9452 (Beebe), 0000-0002-0434-5001 (Kolb)