Simulation for electrical field distribution of the gel culture chamber. (a) Details of the 2D simulation model. The calculation was done only in the region in gray as the boundaries indicated in black were insulated. The electric potential on the surface of the Pt electrodes indicated in red was set at 4 V. (b) Contour plot of the electric field. The electric field around the area corresponding to the TEM was 2.0 V/mm or over.