Unexpected ionic transport behavior in hydrophobic and uncharged conical nanopores.
Fiche publication
Date publication
octobre 2018
Journal
Faraday discussions
Auteurs
Membres identifiés du Cancéropôle Est :
Dr PICAUD Fabien
Tous les auteurs :
Balme S, Picaud F, Lepoitevin M, Bechelany M, Balanzat E, Janot JM
Lien Pubmed
Résumé
We investigated ionic transport behavior in the case of uncharged conical nanopores. To do so, we designed conical nanopores using atomic layer deposition of Al2O3/ZnO nanolaminates and then coated these with trimethylsilane. The experimental results are supported by molecular dynamics simulations. The ionic transport reveals an unexpected behavior: (i) a current rectification and (ii) a constant conductance at low salt concentration which are usually reported for charged conical nanopore. To explain these results, we have considered different assumptions: (i) a default of functionalization, (ii) the adsorption anion and (iii) the slippage. The first one was refuted by the study of the poly-l-lysine transport through the nanopore. To verify the second assumption, we investigate the effect of pH on the current rectification and the molecular dynamics simulations. Finally our study demonstrates that the unexpected ionic transport is provided to a predominant effect of slippage due to the water organization at the solid/liquid interface.
Référence
Faraday Discuss. 2018 10 1;210:69-85