Controlling Polymer Capture and Translocation by Electrostatic Polymer-Pore Interactions

Abstract

Polymer translocation experiments typically involve anionic polyelectrolytes such as DNA molecules driven through negatively charged nanopores. Quantitative modelling of polymer capture to the nanopore followed by translocation therefore necessitates the consideration of the electrostatic barrier resulting from like-charge polymer-pore interactions. To this end, in this work we couple mean-field level electrohydrodynamic equations with the Smoluchowski formalism to characterize the interplay between the electrostatic barrier, the electrophoretic drift, and the electro-osmotic liquid flow. In particular, we find that due to distinct ion density regimes where the salt screening of the drift and barrier effects occur, there exists a characteristic salt concentration maximizing the probability of barrier-limited polymer capture into the pore. We also show that in the barrier-dominated regime, the polymer translocation time increases exponentially with the membrane charge and decays exponentially fast with the pore radius and the salt concentration. These results suggest that the alteration of these parameters in the barrier-driven regime can be an efficient way to control the duration of the translocation process and facilitate more accurate measurements of the ionic current signal in the pore.

References in corpus (13)

• Effect of Salt Concentration on the Electrophoretic Speed of a Polyelectrolyte through a Nanopore
• Translocation frequency of double-stranded DNA through a solid-state nanopore
• DNA translocation through nanopores with salt gradients: The role of osmotic flow
• Effective charge and free energy of DNA inside an ion channel
• Electrophoresis of a polyelectrolyte through a nanopore
• Self-energy limited ion transport in sub-nanometer channels
• Charge neutrality breakdown in confined aqueous electrolytes: theory and simulation
• Electrophoretic Capture of a DNA Chain into a Nanopore
• Origin of translocation barriers for polyelectrolyte chains
• Electrostatics of ions inside the nanopores and trans-membrane channels
• Electrostatic correlations on the ionic selectivity of cylindrical membrane nanopores
• Like-charge attraction and opposite-charge decomplexation between polymers and DNA molecules
• Electrophoresis of a DNA Coil Near a Nanopore

Cited by in corpus (6)

• Multivalent cation induced attraction of anionic polymers by like-charged pores
• Enhanced polymer capture speed and extended translocation time in pressure-solvation traps
• pH-Mediated Regulation of Polymer Transport Through SiN Pores
• Adsorption of polyelectrolytes in the presence of varying dielectric discontinuity between solution and substrate
• Pulling a DNA molecule through a nanopore embedded in an anionic membrane: tension propagation coupled to electrostatics
• An efficient Kinetic Monte Carlo to study analyte capture by a nanopore: Transients, boundary conditions and time-dependent fields