Charge inversion at high ionic strength studied by streaming currents.

Frank H J van der Heyden; Derek Stein; Koen Besteman; Serge G Lemay; Cees Dekker

doi:10.1103/physrevlett.96.224502

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Charge inversion at high ionic strength studied by streaming currents.

Frank H J van der Heyden·Derek Stein·Koen Besteman·Serge G Lemay·Cees Dekker

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Abstract

We report charge inversion, the sign reversal of the effective surface charge in the presence of multivalent counterions, for the biologically relevant regimes of divalent ions and mixtures of monovalent and multivalent ions. Using streaming currents, the pressure-driven transport of countercharges in the diffuse layer, we find that charge inversion occurs in rectangular silica nanochannels at high concentrations of divalent ions. Strong monovalent screening is found to cancel charge inversion, restoring the original surface charge polarity. An analytical model based on ion correlations successfully describes our observations.

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Ion Channels Ions Models, Chemical Nanostructures Osmolar Concentration Silicon Dioxide Journal Article Research Support, Non-U.S. Gov't

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Frank H J van der Heyden, Derek Stein, Koen Besteman, Serge G Lemay, Cees Dekker. 2006-06-06. Charge inversion at high ionic strength studied by streaming currents.. https://doi.org/10.1103/physrevlett.96.224502

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