The Effect of Translocating Cylindrical Particles on the Ionic Current through a Nano-Pore

Loading...
Thumbnail Image
Penn collection
Departmental Papers (MEAM)
Degree type
Discipline
Subject
translocation
coulter counter
cylindrical particle
ionic current
pore
current blockade
Funder
Grant number
License
Copyright date
Distributor
Related resources
Author
Liu, Hui
Qian, Shizhi
Contributor
Abstract

The electric field induced translocation of cylindrical particles through nano-pores with circular cross-sections is studied theoretically. The coupled Nernst-Planck equations (multi-ion model, MIM) for the concentration fields of the ions in solution and the Stokes equation for the flow field are solved simultaneously. The predictions of the multi-ion model are compared with the predictions of two simplified models based on the Poisson-Boltzmann equation (PBM) and the Smoluchowski's slip velocity (SVM). The concentration field, the ionic current though the pore, and the particle's velocity are computed as functions of the particle's size, location, and electric charge; the pore's size and electric charge; the electric field intensity; and the bulk solution's concentration. In qualitative agreement with experimental data, the MIM predicts that, depending on the bulk solution's concentration, the translocating particle may either block or enhance the ionic current. When the thickness of the electric double layer is relatively large, the PBM and SVM predictions do not agree with the MIM predictions. The limitations of the PBM and SVM are delineated. The theoretical predictions are compared with and used to explain experimental data pertaining to the translocation of DNA molecules through nano-pores.

Advisor
Date Range for Data Collection (Start Date)
Date Range for Data Collection (End Date)
Digital Object Identifier
Series name and number
Publication date
2007-02-01
Journal title
Volume number
Issue number
Publisher
Publisher DOI
Journal Issue
Comments
Postprint version. Published in Biophysical Journal, Volume 92, February 2007, pages 1164-1177. Publisher URL: http://dx.doi.org/10.1529/biophysj.106.089268
Recommended citation
Collection