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Low-frequency noise induced by cation exchange fluctuation on the wall of silicon nitride nanopore.

ABSTRACT: Nanopore-based biosensors have attracted attention as highly sensitive microscopes for detecting single molecules in aqueous solutions. However, the ionic current noise through a nanopore degrades the measurement accuracy. In this study, the magnitude of the low-frequency noise in the ionic current through a silicon nitride nanopore was found to change depending on the metal ion species in the aqueous solution. The order of the low-frequency noise magnitudes of the alkali metal ionic current was consistent with the order of the adsorption affinities of the metal ions for the silanol surface of the nanopore (Li

SUBMITTER: Matsui K

PROVIDER: S-EPMC7250840 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Low-frequency noise induced by cation exchange fluctuation on the wall of silicon nitride nanopore.

Matsui Kazuma K Goto Yusuke Y Yanagi Itaru I Akahori Rena R Fujioka Michiru M Ishida Takeshi T Yokoi Takahide T Nakagawa Tatsuo T Takeda Ken-Ichi KI

Scientific reports 20200526 1

Nanopore-based biosensors have attracted attention as highly sensitive microscopes for detecting single molecules in aqueous solutions. However, the ionic current noise through a nanopore degrades the measurement accuracy. In this study, the magnitude of the low-frequency noise in the ionic current through a silicon nitride nanopore was found to change depending on the metal ion species in the aqueous solution. The order of the low-frequency noise magnitudes of the alkali metal ionic current was ...[more]

PMID: 32457511

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