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Updated: May 23, 2026

Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
Published on: August 16, 2016
Transport of long neutral polymers in the semidilute regime through a protein nanopore
Abdel Ghani Oukhaled1, Anne-Laure Biance, Juan Pelta
1LAMBE UMR 8587 CNRS, Universités d'Évry Val d'Essonne and Cergy-Pontoise, 91025 Évry, France.
Abstract:
We investigate the entrance of single poly(ethylene glycol) chains into an α-hemolysin channel. We detect the frequency and duration of the current blockades induced by large neutral polymers, where chain radius is larger than pore diameter. In the semidilute regime, these chains pass only if the monomer concentration is larger than a well-defined threshold. Experiments are performed in a very large domain of concentration and molecular mass, up to 35% and 200 kDa, respectively, which was previously unexplored. The variation of the dwell time as a function of molecular mass shows that the chains are extracted from the semidilute solution in contact with the pore by a reptation mechanism.
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