mt0c00606_si_009.mp4 (4.36 MB)
Electrokinetic Translocation of a Deformable Nanoparticle through a Nanopore
media
posted on 2020-08-04, 14:49 authored by Teng Zhou, Jian Ge, Liuyong Shi, Zhenyu Liu, Yongbo Deng, Yinyin Peng, Xiaohan He, Rongnian Tang, Liping WenThe nanopore-based
biosensing technology is built up on the fluctuation
of the ionic current induced by the electrokinetic translation of
a particle penetrating the nanopore. It is expected that the current
change of a deformable bioparticle is dissimilar from that of a rigid
one. This study theoretically investigated the transient translocation
process of a deformable particle through a nanopore for the first
time. The mathematical model considers the Poisson equation for the
electric potential, the Nernst–Planck equations for the ionic
transport, the Navier–Stokes equations for the flow field,
and the stress–strain equation for the dynamics of the deformable
bioparticle. The arbitrary Lagrangian–Eulerian method is used
for the fully coupled particle-fluid dynamic interaction. Results
show that the deformation degree of the particle, the velocity deviation,
and the current is different from the rigid particle. The deformation
degree of the particle will reach the maximum when the particle passes
a nanopore. Because of the deformation of particles, the total force
applied on deformable particles is larger than that of rigid particles,
resulting in larger velocity deviation and current deviation. The
influences of the ratio of the nanoparticle radius to the Debye length
and surface charge density of the nanopore are also studied. The research
results illustrate the translocation mechanism of a deformable nanoparticle
in the nanopore, which can provide theoretical guidance for the biosensing
technology based on the nanopore.