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Electrical characterization of protein molecules by a solid-state nanopore.

ABSTRACT: The authors measured ionic current blockages caused by protein translocation through voltage-biased silicon nitride nanopores in ionic solution. By calculating the mean amplitude, time duration, and the integral of current blockages, they estimated the relative charge and size of protein molecules at a single molecule level. The authors measured the change in protein charge of bovine serum albumin (BSA) protein induced by pH variation. They also confirmed that BSA molecules indeed traverse nanopores using an improved chemiluminescent analysis. They demonstrated that a larger protein fibrinogen could be distinguished from BSA by a solid-state nanopore measurement.

SUBMITTER: Fologea D

PROVIDER: S-EPMC2288568 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature

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Electrical characterization of protein molecules by a solid-state nanopore.

Fologea Daniel D Ledden Bradley B McNabb David S DS Li Jiali J

Applied physics letters 20070701 5

The authors measured ionic current blockages caused by protein translocation through voltage-biased silicon nitride nanopores in ionic solution. By calculating the mean amplitude, time duration, and the integral of current blockages, they estimated the relative charge and size of protein molecules at a single molecule level. The authors measured the change in protein charge of bovine serum albumin (BSA) protein induced by pH variation. They also confirmed that BSA molecules indeed traverse nanop ...[more]

PMID: 18392111

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