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A nanopore-nanofiber mesh biosensor to control DNA translocation.

ABSTRACT: Solid-state nanopores show promise as single-molecule sensors for biomedical applications, but to increase their resolution and efficiency, analyte molecules must remain longer in the nanopore sensing volume. Here we demonstrate a novel, facile, and customizable nanopore sensor modification that reduces the double-stranded DNA translocation velocity by 2 orders of magnitude or more via interactions outside the nanopore. This is achieved by electrospinning a copolymer nanofiber mesh (NFM) directly onto a solid-state nanopore (NP) chip. The effect of NFMs on dsDNA translocation through an NP is highlighted using a set of NFMs of varying mesh composition that reduce the translocation speed relative to a bare pore from 1- to >100-fold. A representative NFM from this set is effective on DNA as long as 20 kbp, improves the nanopore resolution, and allows discrimination among different DNA lengths.

SUBMITTER: Squires AH

PROVIDER: S-EPMC4039743 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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A nanopore-nanofiber mesh biosensor to control DNA translocation.

Squires Allison H AH Hersey Joseph S JS Grinstaff Mark W MW Meller Amit A

Journal of the American Chemical Society 20131101 44

Solid-state nanopores show promise as single-molecule sensors for biomedical applications, but to increase their resolution and efficiency, analyte molecules must remain longer in the nanopore sensing volume. Here we demonstrate a novel, facile, and customizable nanopore sensor modification that reduces the double-stranded DNA translocation velocity by 2 orders of magnitude or more via interactions outside the nanopore. This is achieved by electrospinning a copolymer nanofiber mesh (NFM) directl ...[more]

PMID: 24143914

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