The effect of counter-ions on the ion selectivity of potassium and sodium ions in nanopores

Issue title: Frontiers in Biomedical Engineering and Biotechnology – Proceedings of the 2nd International Conference on Biomedical Engineering and Biotechnology, 11–13 October 2013, Wuhan, China

Article type: Research Article

Authors: Tang, Dai | Kim, Daejoong^;

Affiliations: Department of Mechanical Engineering, Sogang University, Seoul, Republic of Korea

Note: [] Corresponding author. E-mail: daejoong@sogang.ac.kr, Phone:+82-2-705-8644, Fax:+82-2-712-0799

Abstract: The ion selective transport plays an important role in the function of cell membranes, and promotes the application of artificial permeable membranes. This phenomenon has been studied in case for different diameters and functional groups of nanopores. In this work, we focus on the effect of anions on cation selectivity, in particular the influence of various halide ions on K+ and Na+ selectivity. We adopted molecular dynamics simulations with non-charged nanopores under constant temperature and uniform concentration. The results show K+-selectivity in the solution with Cl- and Na+-selectivity in the solution with Br- and I-. This selectivity, on the contrary, disappears in the solution with F-. We also investigate the change of the hydration shell of ions and cation-anion interactions between in the bulk region and in the nanopores, which could explain this selective phenomenon.

Keywords: ion selectivity, halide ions, potassium and sodium, hydration shell of ion

DOI: 10.3233/BME-130822

Journal: Bio-Medical Materials and Engineering, vol. 24, no. 1, pp. 383-390, 2014