Abstract：In order to explore the theoretical mechanism of electroporation (EP),a 2D-axisymmetric model of single cell EP was established in this paper. The asymptotic electroporation equation and the pore radii evolution equation were included in the model to express the pore density and radii of EP. The perforation area was calculated more accurate by the axisymmetry of the model. Thus the temporal and spatial distribution characteristics of the micropores can be obtained,and the influence of the field strength and pulse width on EP was discussed. The results showed that 7 862 micropores were produced under the microsecond pulse electric field (μsPEF) of 100 μs and 2 kV/cm,and the perforation area accounted for 6.3% of the cell surface;the temporal and spatial distribution of the parameters of EP were consistent with the results of literature,which verified the correctness of the constructed model;in the range of 1 to 5 kV/cm,the number of pores was directly proportional to the field strength,the pore radius at P1 was in inverse proportion to the field strength,while the ratio of pore area to cell area increased from 1.3% to 12.9%;two groups of nsPEF and μsPEF with the same energy were selected for comparative study,it was found that at the end of the pulse,the number of pores generated by the former was 353.1 times of the latter one,and the pore radius at P1 of the latter was 19.3 times of the former one,indicated that nsPEF was conducive to the growth of the number of pores,while the μsPEF was conducive to the expansion of the pore radii. The simulation results showed that microporous characteristics determined the occurrence and development of EP,and the accurate calculation of microporosity was the key to explain the effect of EP.
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