During nsPEF applications, electrical pulses of 10, 60 or 300 ns durations
were applied to cells using electric field amplitudes as high as 300 kV/cm. Because of the ultra-short pulse durations, the
energy transferred to cells is negligible, and only non-thermal effects are observed.We investigated the genotoxicity of nsPEF
on adherent and non-adherent cell lines including 10 human lines and one mouse cell line with different origin and growth
characteristics. We present data examining the effects of nsPEF exposure on cell survival assessed by clonogenic formation
or live cell count; DNA damage determined by the comet assay and chromosome aberrations; and cell cycle parameters by
measuring the mitotic indices of exposed cells. Using each of these indicators, we observed differential effects among cell types
with non-adherent cells being more sensitive to the genotoxic effects of nsPEF exposures than adherent cells. Non-adherent
cultures showed a rapid decrease in cell viability (90%), induction of DNA damage, and a decrease in the number of cells
reaching mitosis after one 60 ns pulse with an electric field intensity of 60 kV/cm. These effects were not observed in cells
grown as adherent cultures, with the exception of the mouse 3T3 cell line, which showed survival characteristics similar to
non-adherent cultures. These data suggest that nsPEF genotoxicity may be cell type specific, and therefore have potential
applications in the selective removal of one cell type from another, for example, in diseased states.