Paper Info
Title
Effects of (Small) Permanent Charge and Channel Geometry on Ionic Flows via Classical Poisson-Nernst-Planck Models.
Abstract
In this work, we examine effects of permanent charges on ionic flows through ion channels via a quasi-one-dimensional classical Poisson-Nernst-Planck (PNP) model. The geometry of the three-dimensional channel is presented in this model to a certain extent, which is crucial for the study in this paper. Two ion species, one positively charged and one negatively charged, are considered with a simple profile of permanent charges: zeros at the two end regions and a constant Q(0) over the middle region. The classical PNP model can be viewed as a boundary value problem (BVP) of a singularly perturbed system. The singular orbit of the BVP depends on Q(0) in a regular way. Assuming vertical bar Q0 vertical bar is small, a regular perturbation analysis is carried out for the singular orbit. Our analysis indicates that effects of permanent charges depend on a rich interplay between boundary conditions and the channel geometry. Furthermore, interesting common features are revealed: for Q(0) = 0, only an average quantity of the channel geometry plays a role; however, for Q(0) not equal 0, details of the channel geometry matter; in particular, to optimize effects of a permanent charge, the channel should have a short and narrow neck within which the permanent charge is confined. The latter is consistent with structures of typical ion channels.
Year
DOI
Venue
2015
10.1137/140992527
SIAM JOURNAL ON APPLIED MATHEMATICS
Keywords
Field
DocType
ionic flow,permanent charge,channel geometry
Ionic bonding,Orbit,Boundary value problem,Perturbation theory,Mathematical analysis,Communication channel,Planck,Geometry,Classical mechanics,Mathematics,Ion,Nernst equation
Journal
Volume
Issue
ISSN
75
1
0036-1399
Citations 
PageRank 
References 
0
0.34
0
Authors
3
Name
Order
Citations
PageRank
Shuguan Ji100.68
Weishi Liu2285.34
Mingji Zhang311.72