Issue 32, 2023, Issue in Progress

Dielectric polarization-based separations in an ionic solution


A novel non-electrophoretic, electric field-based separation mechanism capable of transporting ions based on their dielectric properties is presented here for the first time. Though this polarization-based mechanism behaves similarly to dielectrophoresis, the separation mechanism is remarkably very efficient at small length scales compared to any dielectrophoretic separation mechanism for particles. For an applied electric field of strength as low as ∼0.75 MV m−1 across a 100 μm channel, the working solute – sodium fluorescein – is shown to decrease in its concentration by ≈20% in electric field region relative to the non electric field region. The existing macroscopic theoretical models like electrohydrodynamics and equilibrium thermodynamics are shown to underestimate the concentration change by two orders of magnitude for the same electric field strength. This surprisingly large difference between theory and experimental results suggests that the electric field-based equilibrium thermodynamic model lacks a key physics.

Graphical abstract: Dielectric polarization-based separations in an ionic solution

Article information

Article type
12 May 2023
23 Jun 2023
First published
24 Jul 2023
This article is Open Access
Creative Commons BY license

RSC Adv., 2023,13, 22185-22192

Dielectric polarization-based separations in an ionic solution

G. Anand, S. Safaripour and C. Snoeyink, RSC Adv., 2023, 13, 22185 DOI: 10.1039/D3RA03169A

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity