Objective   To investigate the impact of pulse electric fields (PEFs) on membrane breakdown

necrosis and apoptosis of HeLa cells when irreversible electroporation (IRE) was performed on it. MethodsPEFs with a permanent duration of 100 μs

a frequency of 1 Hz and pulse of 8 pieces were performed on HeLa cells (2×10

6

/ml). The electric field intensity was increased from 250 V/cm to 2 500 V/cm gradually with 250 V/cm for each time. Propidium Iodide (PI) was used to trace the breakdown of cell membrane with the aid of flow cytometry according to the manufacturer’s protocol. Cell counting kit-8 (CCK-8) assay was used to examine survival of HeLa cells after treated with IRE. HeLa cells we

re double-stained with Annexin V kit then analyzed with flow cytometry for apoptosis and necrosis.  Results  The reversible electroporation threshold of HeLa cells was 750 V/cm. The apoptotic threshold ranged from 1 250 V/cm to 1 500 V/cm. The necrotic threshold was about 1 750V/cm.  Conclusion  Besides necrosis due to IRE

apoptosis also played an important role during IRE ablating HeLa cells. The areas of PEF parameters inducing apoptosis and necrosis are overlapped with each other.