Modulating nanopore size and ion transport using (Anti)-Polyelectrolyte effects inspired by the nuclear pore complex

Area of Science:

• Nanotechnology
• Materials Science
• Biomimetics

Background:

• The nuclear pore complex (NPC) regulates transport via complex mechanisms.
• Synthetic nanopores offer platforms to mimic biological transport.
• (Anti)-polyelectrolyte effects provide a route to control nanopore properties.

Purpose of the Study:

• To investigate (anti)-polyelectrolyte effects on synthetic nanopore ion transport.
• To control ionic selectivity and rectification in nanopores.
• To mimic nuclear pore complex (NPC) functions.

Main Methods:

• Fabrication of single bicylindrical nanopores in PET membranes.
• Functionalization with polyelectrolyte layers (PEI/HA, PLL/PAA).
• Modulation of nanopore properties via pH and ionic strength variations.

Main Results:

• Ion selectivity and transport were significantly influenced by charge density and surface polarity at low salt concentrations.
• Conformational changes (expansion/compaction) of polyelectrolytes affected conductance at higher salt concentrations.
• Charge inversion and molecular expansion were identified as key modulators of nanopore transport.

Conclusions:

• Polyelectrolyte coatings enable tunable control over nanopore size and ion transport.
• pH and ionic environment are critical factors in modulating nanopore behavior.
• Findings provide a basis for designing selective ion channels for nanofluidics, filtration, and biosensing.