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Heterogeneity of multiple-pore membranes investigated with ion conductance microscopy.

ABSTRACT: Heterogeneous conductance of individual pores on a porous membrane was studied with a four-electrode scanning ion conductance microscope (SICM). Application of a potential difference across the membrane resulted in migration of ions through nanopores, where subsequent conductance changes were measured by a nanopipet positioned above the nanopore as a change in pipet current. Current responses of single-pore membranes and individual pores within a multipore membrane were examined and demonstrated variations in ion current rectification (ICR) ratios due to the small differences in pore geometries.

SUBMITTER: Zhou Y

PROVIDER: S-EPMC3310308 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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Heterogeneity of multiple-pore membranes investigated with ion conductance microscopy.

Zhou Yi Y Chen Chiao-Chen CC Baker Lane A LA

Analytical chemistry 20120229 6

Heterogeneous conductance of individual pores on a porous membrane was studied with a four-electrode scanning ion conductance microscope (SICM). Application of a potential difference across the membrane resulted in migration of ions through nanopores, where subsequent conductance changes were measured by a nanopipet positioned above the nanopore as a change in pipet current. Current responses of single-pore membranes and individual pores within a multipore membrane were examined and demonstrated ...[more]

PMID: 22390616

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