title: Improving signal-to-noise performance for DNA translocation in solid-state nanopores at MHz bandwidths.
abstract: DNA sequencing using solid-state nanopores is, in part, impeded by the relatively high noise and low bandwidth of the current state-of-the-art translocation measurements. In this Letter, we measure the ion current noise through sub 10 nm thick Si3N4 nanopores at bandwidths up to 1 MHz. At these bandwidths, the input-referred current noise is dominated by the amplifier's voltage noise acting across the total capacitance at the amplifier input. By reducing the nanopore chip capacitance to the 1-5 pF range by adding thick insulating layers to the chip surface, we are able to transition to a regime in which input-referred current noise (∼ 117-150 pArms at 1 MHz in 1 M KCl solution) is dominated by the effects of the input capacitance of the amplifier itself. The signal-to-noise ratios (SNRs) reported here range from 15 to 20 at 1 MHz for dsDNA translocations through nanopores with diameters from 4 to 8 nm with applied voltages from 200 to 800 mV. Further advances in bandwidth and SNR will require new amplifier designs that reduce both input capacitance and input-referred amplifier noise.
authors.affiliation: Department of Physics and Astronomy, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States.
authors.forename: Adrian
authors.initials: A
authors.lastname: Balan
authors.forename: Bartholomeus
authors.initials: B
authors.lastname: Machielse
authors.forename: David
authors.initials: D
authors.lastname: Niedzwiecki
authors.forename: Jianxun
authors.initials: J
authors.lastname: Lin
authors.forename: Peijie
authors.initials: P
authors.lastname: Ong
authors.forename: Rebecca
authors.initials: R
authors.lastname: Engelke
authors.forename: Kenneth L
authors.initials: KL
authors.lastname: Shepard
authors.forename: Marija
authors.initials: M
authors.lastname: Drndić
mesh_terms: D003217:Conductometry / Q000295:instrumentation*; D004247:DNA / Q000032:analysis* / Q000737:chemistry* / Q000235:genetics; D004867:Equipment Design; D019544:Equipment Failure Analysis; D009038:Motion; D058608:Nanopores / Q000648:ultrastructure*; D036103:Nanotechnology / Q000295:instrumentation*; D011846:Radio Waves; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA / Q000295:instrumentation*
chemical_list: D004247:DNA
keywords: DNA; Nanopore; TEM; capacitance; sequencing; silicon nitride