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05:33
Solid-state Graft Copolymer Electrolytes for Lithium Battery Applications
Published on: August 12, 2013
Multivalent cation induced attraction of anionic polymers by like-charged pores
Sahin Buyukdagli1, T Ala-Nissila2
1Department of Physics, Bilkent University, Ankara 06800, Turkey.
The Journal of Chemical Physics
|October 17, 2017
Summary
Adding multivalent cations to electrolyte solutions overcomes electrostatic barriers, enabling anionic polyelectrolytes to be captured by negatively charged nanopores. This enhances polymer sensing device efficiency.
Area of Science:
- Nanotechnology
- Polymer Science
- Physical Chemistry
Background:
- Nanopore-based polymer sensing relies on efficient capture of anionic polyelectrolytes by like-charged pores.
- An electrostatic barrier from repulsive polymer-pore interactions hinders this capture process.
Purpose of the Study:
- To investigate methods for overcoming the electrostatic barrier in nanopore-based polymer sensing.
- To explore the role of multivalent cations in facilitating polyelectrolyte capture by charged nanopores.
Main Methods:
- Development of a correlation-corrected theoretical model.
- Analysis of electrostatic interactions between polymers, pores, and electrolyte ions.
Main Results:
- Addition of multivalent cations effectively screens the electrostatic barrier.
- Cation adsorption within the pore creates an attractive force on the polymer.
- Like-charge polymer-pore attraction is observed beyond a critical cation concentration.
- Monovalent salts suppress this attraction, while membrane charge strength and pore confinement enhance it.
Conclusions:
- Multivalent cations can induce attraction between like-charged polymers and nanopores.
- This phenomenon offers a strategy to enhance polymer adsorption and control polymer motion in nanopore devices.
- The findings have implications for improving the efficiency of nanopore-based sensing and translocation experiments.
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