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Single-nanopore investigations with ion conductance microscopy.

ABSTRACT: A three-electrode scanning ion conductance microscope (SICM) was used to investigate the local current-voltage properties of a single nanopore. In this experimental configuration, the response measured is a function of changes in the resistances involved in the pathways of ion migration. Single-nanopore membranes utilized in this study were prepared with an epoxy painting procedure to isolate a single nanopore from a track-etch multipore membrane. Current-voltage responses measured with the SICM probe in the vicinity of a single nanopore were investigated in detail and agreed well with equivalent circuit models proposed in this study. With this modified SICM, the current-voltage responses characterized for the case of a single cylindrical pore and a single conical pore exhibit distinct conductance properties that originate from the geometry of nanopores.

SUBMITTER: Chen CC

PROVIDER: S-EPMC3202087 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature

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Single-nanopore investigations with ion conductance microscopy.

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

ACS nano 20110926 10

A three-electrode scanning ion conductance microscope (SICM) was used to investigate the local current-voltage properties of a single nanopore. In this experimental configuration, the response measured is a function of changes in the resistances involved in the pathways of ion migration. Single-nanopore membranes utilized in this study were prepared with an epoxy painting procedure to isolate a single nanopore from a track-etch multipore membrane. Current-voltage responses measured with the SICM ...[more]

PMID: 21923184

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