A stochastic model for DNA translocation through an electropore

A 1D Fokker-Planck simulation of DNA translocation through an electropore under finite pulses is presented. This study is motivated by applications relevant to DNA electrotransfer into biological cells via electroporation. The results review important insights. The translocation may occur on two disparate time scales, the electrophoretic time (~ ms), and the diffusive time (~ s), depending on the pulse length. Furthermore, a power-law correlation is observed, F-PST ~ (V_mt_p)^a/N^b, where F-PST is the final probability of successful translocation, V_m is the transmembrane potential, t_p is the pulse length, and N is the DNA length in segments. The values for a and b are close to 1 and 1.5, respectively. The simulated results are compared with previous data to interpret the trends. In particular, the diffusive time scale is used to explain the frequency dependence observed in electroporation experiments with uni- and bi-polar pulse trains. The predictions from the current model can be harnessed to help design experiments for the further understanding and quantification of DNA electrotransfer.