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Electrochemical Amplification in Side-by-Side Attoliter Nanogap Transducers.

ABSTRACT: We report a strategy for the fabrication of a new type of electrochemical nanogap transducer. These nanogap devices are based on signal amplification by redox cycling. Using two steps of electron-beam lithography, vertical gold electrodes are fabricated side by side at a 70 nm distance encompassing a 20 attoliter open nanogap volume. We demonstrate a current amplification factor of 2.5 as well as the possibility to detect the signal of only 60 analyte molecules occupying the detection volume. Experimental voltammetry results are compared to calculations from finite element analysis.

SUBMITTER: Zafarani HR

PROVIDER: S-EPMC5485373 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Electrochemical Amplification in Side-by-Side Attoliter Nanogap Transducers.

Zafarani Hamid Reza HR Mathwig Klaus K Sudhölter Ernst J R EJR Rassaei Liza L

ACS sensors 20170516 6

We report a strategy for the fabrication of a new type of electrochemical nanogap transducer. These nanogap devices are based on signal amplification by redox cycling. Using two steps of electron-beam lithography, vertical gold electrodes are fabricated side by side at a 70 nm distance encompassing a 20 attoliter open nanogap volume. We demonstrate a current amplification factor of 2.5 as well as the possibility to detect the signal of only 60 analyte molecules occupying the detection volume. Ex ...[more]

PMID: 28670622

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