Fine-tuning the Size and Minimizing the Noise of Solid-state Nanopores

Abstract

Solid-state nanopores have emerged as a versatile tool for the characterization of single biomolecules such as nucleic acids and proteins 1 . However, the creation of a nanopore in a thin insulating membrane remains challenging. Fabrication methods involving specialized focused electron beam systems can produce well-defined nanopores, but yield of reliable and low-noise nanopores in commercially available membranes remains low 2,3 and size control is nontrivial 4,5.Here, the application of high electric fields to fine-tune the size of the nanopore while ensuring optimal low-noise performance is demonstrated. These short pulses of high electric field are used to produce a pristine electrical signal and allow for enlarging of nanopores with subnanometer precision upon prolonged exposure. This method is performed in situ in an aqueous environment using standard laboratory equipment, improving the yield and reproducibility of solid-state nanopore fabrication.

Fast Fabrication Nanopores on a PMMA Membrane by a Local High Electric Field Controlled Breakdown

“…The interaction between the ionic solution and the nanopore wall [14], as well as the membrane surface, are the primary contributors to nanopore noise [15,16]. This noise is directly influenced by the material and structure of the membrane [17][18][19], including electron mobility, dielectric constant, contact area, and thickness. Using a low dielectric constant and reducing the suspended area are two effective methods for reducing noise in nanopores.…”