Nanopore Positive Pulse Detection of DNA with Salt Gradients

Abstract

Nanopore based sensors have been widely spread utilized for detection and analysis of various single charged molecules. However, collision and trap events also block the ionic current that interferes recording the actually translocation events. In order to resolve the problem, we propose inducing a salt gradient to turn the pulse form negative to positive. And the salt gradients dependence of pulse signals ranging from 1 M (cis & trans) to 1 M (cis) - 4 M (trans) is mapped. Experiment results demonstrate that applying a high salt gradient prolong translocation time 1.5 times and increase molecule capture rate by a fact of 3. It is benefit for nanopore further application.