Dynamics of polymer translocation through a nanopore induced by different sizes of crowding agents

Using both theoretical analysis and Langevin dynamics simulations in two dimensions, we investigate the dynamics of polymer translocation through a nanopore induced by different sizes of the mobile crowding agents, where the crowding agents have equal area fraction φ and their diameters are σ and σb ≥ σ at cis and trans sides, respectively. The chain prefers moving to the side with bigger crowding agents as expected, however, we find the size difference between crowding agents plays a complicated role in the probability of polymer translocation from cis to trans side, the translocation time τ and its distribution, and the translocation exponent. In particular, with increasing σb, the translocation probability shows a maximum value and τ has a minimum value. These results can be interpreted by the effective driving force, which always increases with increasing φ but has a maximum value with increasing σb.