Effects of nanopore size on the flow-induced star polymer translocation

Abstract

We study the effects of the nanopore size on the flow-induced capture of the star polymer by a nanopore and the afterward translocation, using a hybrid simulation method that couples point particles into a fluctuating lattice-Boltzmann fluid. Our simulation demonstrates that the optimal forward arm number decreases slowly with the increase of the length of the nanopore. Compared to the minor effect of the length of the nanopore, the optimal forward arm number obviously increases with the increase of the width of the nanopore, which can clarify the current controversial issue for the optimal forward arm number between the theory and experiments. In addition, our results indicate that the critical velocity flux of the star polymer is independent of the nanopore size. Our work bridges the experimental results and the theoretical understanding, which can provide comprehensive insights for the characterization and the purification of the star polymers.

Single molecule electrophoresis of star polymers through nanopores: Simulations

“…In contrast to our observation, fluid flow driven star polymer translocation shows a non-monotonic trend in the probability of successful translocation with respect to the number of leading arms. 17 The flow field drags the star polymer into the nanopore and makes conformations with more than one leading arm more probable, giving rise to a maximum probability of successful translocation for more than one leading arm.…”

“…11,12 Understanding the behavior of star polymers under confinement has been the focus of various recent studies. [13][14][15][16][17][18][19][20][21][22][23][24] This is an interesting problem because the distribution of arms of the star polymer under confinement can lead to rich dynamics, and developing such an understanding is required in devising many applications. For asymmetric star polymers, arm length has been found to have a profound effect on the transport properties of the polymer in gel electrophoresis.…”

“…16 In the presence of a flowing fluid, conformational dynamics of a star polymer become even more important. 17 The critical capture rate of a star polymer into a nanopore is predicted to have a strong dependence on its functionality (number of arms) for certain arm lengths. 18,19 The star polymer is found to migrate away from the walls of a wide cylindrical pipe due to the flow along the pipe axis, with the extent of migration increasing for stars with higher functionalities.…”

Star Polymer Translocation into a Spheroidal Cavity

“…For the purpose of the subsequent discussion, a leading arm is defined to be one whose center of mass (COM) enters the nanopore before the branch point. [24,25] All other arms are classified as trailing arms. The effect of f and R upon the average number of leading arms, f l , is illustrated in Figure 2.…”

“…[21,22] As such, the phenomenon of star polymer translocation through a nanopore has attracted increasing attention over the last decade. [21][22][23][24][25][26][27][28] One of the first studies that investigated the effect of star polymer functionality upon the translocation time, τ was electric field strength, E, upon τ. They found τ to exhibit weaker dependence upon κ for larger N and α to be sensitive to the values of κ and E.…”