State Key Laboratory of Analytical Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, 210023 Nanjing, P. R. China.
Chemistry and Biomedicine Innovation Center (ChemBIC), Nanjing University, 210023 Nanjing, P. R. China.
ACS Appl Mater Interfaces. 2020 Jun 17;12(24):26926-26935. doi: 10.1021/acsami.0c05626. Epub 2020 Jun 2.
Electrophysiological measurement of molecular translocation through a nanopore is the fundamental basis of nanopore sensing. Free translocation of nucleic acids however is normally so fast that the identities of the compounds are not clearly resolvable. Inspired by recent progress in fluorescence imaging based nanopore sensing, we found that during electrophysiology measurements, translocation of nucleic acids is also retarded whenever a calcium flux around the pore vicinity is established. The residence time of nucleic acids has been extended to tens of milliseconds, a result of the strong coupling between nucleic acids and free calcium ions. The methodology presented here is applicable to both DNAs and RNAs and is able to clearly discriminate between different RNA homopolymers. This offers new insights for calcium imaging based nanopore sensing and suggests a new strategy of electrophysiology-based nanopore sensing aimed at a retarded motion of nucleic acids.
通过纳米孔进行分子迁移的电生理学测量是纳米孔传感的基本基础。然而，由于核酸的自由迁移通常非常快，以至于无法清楚地区分化合物的身份。受基于荧光成像的纳米孔传感的最新进展的启发，我们发现，在电生理学测量过程中，只要在孔附近建立钙通量，核酸的迁移就会被延迟。核酸的停留时间已延长至数十毫秒，这是核酸与游离钙离子之间强耦合的结果。这里提出的方法适用于 DNA 和 RNA，并且能够清楚地区分不同的 RNA 同聚物。这为基于钙成像的纳米孔传感提供了新的见解，并提出了一种基于电生理学的纳米孔传感的新策略，旨在减缓核酸的运动。
