title: Ion transport and selectivity in nanopores with spatially inhomogeneous fixed charge distributions.
abstract: Polymeric nanopores with fixed charges show ionic selectivity when immersed in aqueous electrolyte solutions. The understanding of the electrical interaction between these charges and the mobile ions confined in the inside nanopore solution is the key issue in the design of potential applications. The authors have theoretically described the effects that spatially inhomogeneous fixed charge distributions exert on the ionic transport and selectivity properties of the nanopore. A comprehensive set of one-dimensional distributions including the skin, core, cluster, and asymmetric cases are analyzed on the basis of the Nernst-Planck equations. Current-voltage curves, nanopore potentials, and transport numbers are calculated for the above distributions and compared with those obtained for a homogeneously charged nanopore with the same average fixed charge concentration. The authors have discussed if an appropriate design of the spatial fixed charge inhomogeneity can lead to an enhancement of the transport and selectivity with respect to the homogeneous nanopore case. Finally, they have compared the theoretical predictions with relevant experimental data.
authors.affiliation: Departament de Física Aplicada, Universitat Politècnica de València, Camino de Vera s/n, E-46022 Valencia, Spain. patraho@fis.upv.es
authors.forename: Patricio
authors.initials: P
authors.lastname: Ramírez
authors.forename: Vicente
authors.initials: V
authors.lastname: Gómez
authors.forename: Javier
authors.initials: J
authors.lastname: Cervera
authors.forename: Birgitta
authors.initials: B
authors.lastname: Schiedt
authors.forename: Salvador
authors.initials: S
authors.lastname: Mafé
mesh_terms: D016880:Anisotropy; D001704:Biopolymers / Q000737:chemistry*; D003198:Computer Simulation; D015640:Ion Channel Gating; D007473:Ion Channels / Q000737:chemistry*; D017136:Ion Transport; D008956:Models, Chemical; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D016062:Porosity; D055672:Static Electricity
chemical_list: D001704:Biopolymers; D007473:Ion Channels