钙在不对称纳米孔中诱导产生的负增量电阻。

Negative incremental resistance induced by calcium in asymmetric nanopores.

作者信息

Siwy Zuzanna S, Powell Matthew R, Kalman Eric, Astumian R Dean, Eisenberg Robert S

机构信息

Department of Physics and Astronomy, University of California, Irvine, 92697, USA.

出版信息

Nano Lett. 2006 Mar;6(3):473-7. doi: 10.1021/nl0524290.

DOI:10.1021/nl0524290

PMID:16522045

Abstract

Single polymer nanopores with permanent surface charges act as rectifiers of ionic current. The pores are tapered cones with narrow openings of several nanometers and wide openings of approximately 1 mum. The pores are cation-selective, and in symmetric solutions of potassium chloride they rectify the flow of potassium ions from the small opening toward the wide opening. Millimolar concentrations of calcium reverse the rectification, and a negative incremental resistance is observed. These observations can be interpreted by a model containing flashing ratchets.

摘要

具有永久表面电荷的单一聚合物纳米孔可作为离子电流的整流器。这些孔是锥形的，窄开口为几纳米，宽开口约为1微米。这些孔具有阳离子选择性，在氯化钾对称溶液中，它们使钾离子从小开口向大开口流动的方向发生整流。毫摩尔浓度的钙会使整流方向反转，并观察到负增量电阻。这些观察结果可以用一个包含闪烁棘轮的模型来解释。