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Label-free optical detection of biomolecular translocation through nanopore arrays.

ABSTRACT: In recent years, nanopores have emerged as exceptionally promising single-molecule sensors due to their ability to detect biomolecules at subfemtomole levels in a label-free manner. Development of a high-throughput nanopore-based biosensor requires multiplexing of nanopore measurements. Electrical detection, however, poses a challenge, as each nanopore circuit must be electrically independent, which requires complex nanofluidics and embedded electrodes. Here, we present an optical method for simultaneous measurements of the ionic current across an array of solid-state nanopores, requiring no additional fabrication steps. Proof-of-principle experiments are conducted that show simultaneous optical detection and characterization of ssDNA and dsDNA using an array of pores. Through a comparison with electrical measurements, we show that optical measurements are capable of accessing equivalent transmembrane current information.

SUBMITTER: Ivankin A

PROVIDER: S-EPMC4212781 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Label-free optical detection of biomolecular translocation through nanopore arrays.

Ivankin Andrey A Henley Robert Y RY Larkin Joseph J Carson Spencer S Toscano Michael L ML Wanunu Meni M

ACS nano 20140922 10

In recent years, nanopores have emerged as exceptionally promising single-molecule sensors due to their ability to detect biomolecules at subfemtomole levels in a label-free manner. Development of a high-throughput nanopore-based biosensor requires multiplexing of nanopore measurements. Electrical detection, however, poses a challenge, as each nanopore circuit must be electrically independent, which requires complex nanofluidics and embedded electrodes. Here, we present an optical method for sim ...[more]

PMID: 25232895

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