Slowed Down Double-Stranded DNA Transport through Solid-State Nanopores by using a Lithium Chloride Concentration Gradient

Abstract

accessible synthetic nanopore fabrication approach, controlled breakdown (CDB). Since CDB uses conductance feedback to monitor the nanopore fabrication, it cannot tell whether there is a large single nanopore or multiple small nanopores in the membrane. In this work, we found that despite the stochastic process during the breakdown, nanopores created via breakdown in a SiN x membrane tend to have the same scale. We proposed a resistance model to govern the multiple nanopores formation by the conductance feedback -the number of nanopores in the membrane was determined by the membrane resistance and the nanopore sizes were controlled by the enlargement electric field. We further characterized our multiple nanopores by transmission electron microscopy (TEM) imaging and the fluorescence of Ca 2þ -activated dyes. We anticipate that by combining with optical measurements, this fabrication approach could accelerate the process of nanopore sensing towards a highthroughput and multichannel technique.