Electrokinetic Nanorod Translocation through a Dual-Nanopipette

Glass nanopipettes, as important sensing tools, have
attracted
great interest due to their wide range of applications in detecting
single molecules, nanoparticles, and cells. In this study, we investigated
the translocation behavior of nanorod particles through dual-nanopipettes
using a transient continuum-based model based on an arbitrary Lagrangian–Eulerian
approach. Our findings indicate that the translocation of nanorods
is slowed down in the dual-nanopipette system, especially in the dual-nanopipette
system with a nanobridge. These results are in qualitative agreement
with previous experimental findings reported in the literature. Additionally,
the translocation of nanorods is influenced by factors such as bulk
concentration, initial location of the nanorod, and surface charge
of the nanopipette. Notably, when the surface charge density of the
nanopipette is relatively high and the initial location of the nanorod
is in the reservoir, the nanorod can hardly enter the nanopipette,
resulting in a relatively low translocation efficiency. However, the
translocation efficiency can be improved by initially positioning
the nanorod in one of the barrels. The resulting dual-blockade current
signal can be used to correlate the characteristics of the nanorod.