Precise control of the size and noise of solid-state nanopores using high electric fields.

Department of Physics, University of Ottawa, Ottawa, ON, Canada.
Nanotechnology (Impact Factor: 3.67). 09/2012; 23(40):405301. DOI: 10.1088/0957-4484/23/40/405301
Source: PubMed

ABSTRACT We present a methodology for preparing silicon nitride nanopores that provides in situ control of size with sub-nanometer precision while simultaneously reducing electrical noise by up to three orders of magnitude through the cyclic application of high electric fields in an aqueous environment. Over 90% of nanopores treated with this technique display desirable noise characteristics and readily exhibit translocation of double-stranded DNA molecules. Furthermore, previously used nanopores with degraded electrical properties can be rejuvenated and used for further single-molecule experiments.

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