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DNA-graphene interactions during translocation through nanogaps.

ABSTRACT: We study how double-stranded DNA translocates through graphene nanogaps. Nanogaps are fabricated with a novel capillary-force induced graphene nanogap formation technique. DNA translocation signatures for nanogaps are qualitatively different from those obtained with circular nanopores, owing to the distinct shape of the gaps discussed here. Translocation time and conductance values vary by ? 100%, which we suggest are caused by local gap width variations. We also observe exponentially relaxing current traces. We suggest that slow relaxation of the graphene membrane following DNA translocation may be responsible. We conclude that DNA-graphene interactions are important, and need to be considered for graphene-nanogap based devices. This work further opens up new avenues for direct read of single molecule activitities, and possibly sequencing.

SUBMITTER: Patel HN

PROVIDER: S-EPMC5291421 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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DNA-graphene interactions during translocation through nanogaps.

Patel Hiral N HN Carroll Ian I Lopez Rodolfo R Sankararaman Sandeep S Etienne Charles C Kodigala Subba Ramaiah SR Paul Mark R MR Postma Henk W Ch HW

PloS one 20170203 2

We study how double-stranded DNA translocates through graphene nanogaps. Nanogaps are fabricated with a novel capillary-force induced graphene nanogap formation technique. DNA translocation signatures for nanogaps are qualitatively different from those obtained with circular nanopores, owing to the distinct shape of the gaps discussed here. Translocation time and conductance values vary by ∼ 100%, which we suggest are caused by local gap width variations. We also observe exponentially relaxing c ...[more]

PMID: 28158244

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