ABSTRACT
In this chapter, the electric field-induced translocation of a cylindrical nanoparticle through a nanopore is theoretically investigated with full consideration of the particle-fluid-electric field-ionic concentration field interactions. The coupled Poisson-Boltzmann (PB) equation for the ionic concentrations and the electric field stemming from the charged surfaces, the Laplace equation for the electric field externally imposed, the modified Stokes equations for the flow field, and the Newton equations for particle translation and rotation are simultaneously solved using the arbitrary Lagrangian –Eulerian (ALE) finite element method. The dynamic electrokinetic translocation of a cylindrical nanoparticle through a nanopore and the corresponding ionic current response are investigated as functions of the electric field intensity imposed, the electrical double layer (EDL) thickness, the nanopore’s surface charge density, and the particle’s initial orientation and lateral offset from the centerline of the nanopore. The translocating particle blocks the ionic current when the EDLs of the particle and the nanopore are not overlapped, and the predictions are in qualitative agreement with the existing experimental observations.
