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Effect of concentration gradient on ionic current rectification in polyethyleneimine modified glass nano-pipettes.

ABSTRACT: Ion current rectification dependent on the concentration gradient of KCl solutions was systematically investigated in polyethyleneimine modified glass nano-pipettes with inner diameter of 105?nm. Peak shape dependence of the rectification factor on outer KCl solution concentration was observed when inner KCl solution with concentration from 1?mM to 500?mM was used. The peak shape dependence was also observed when the concentrations of the inner and outer KCl solutions were identically controlled. The peak shape in the ion current rectification could be explained by the ion conductance changes through the conical nano-pipette, which result from modulation of ion concentration.

SUBMITTER: Deng XL

PROVIDER: S-EPMC3915318 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature

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Effect of concentration gradient on ionic current rectification in polyethyleneimine modified glass nano-pipettes.

Deng Xiao Long XL Takami Tomohide T Son Jong Wan JW Kang Eun Ji EJ Kawai Tomoji T Park Bae Ho BH

Scientific reports 20140206

Ion current rectification dependent on the concentration gradient of KCl solutions was systematically investigated in polyethyleneimine modified glass nano-pipettes with inner diameter of 105 nm. Peak shape dependence of the rectification factor on outer KCl solution concentration was observed when inner KCl solution with concentration from 1 mM to 500 mM was used. The peak shape dependence was also observed when the concentrations of the inner and outer KCl solutions were identically controlled ...[more]

PMID: 24500036

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