单个双链DNA分子中不存在固有电导率。

Absence of intrinsic electric conductivity in single dsDNA molecules.

作者信息

Kleine H, Wilke R, Pelargus Ch, Rott K, Pühler A, Reiss G, Ros R, Anselmetti D

机构信息

Experimental Biophysics, Faculty of Physics, Bielefeld University, Universitätsstrasse 25, D-33615 Bielefeld, Germany.

出版信息

J Biotechnol. 2004 Aug 26;112(1-2):91-5. doi: 10.1016/j.jbiotec.2004.04.031.

DOI:10.1016/j.jbiotec.2004.04.031

PMID:15288944

Abstract

The intrinsic dc conductivity of long, individual lambda phage dsDNA molecules has been investigated by ultrasensitive low current-voltage-spectroscopy (IV) under ambient conditions and controlled low humidity inert gas atmosphere on microfabricated metal-insulator-metal gap structures. We found a strong dependence of the measured conductivity on the apparent humidity, which we attribute to capillary condensation of water to the immobilized DNA molecules, giving rise to additional ionic currents. Additional IV-spectroscopy experiments under controlled argon atmosphere always revealed a significant drop in electrical conductivity to 4 x 10(-15)AV(-1)microm(-1), indicating almost no considerable contribution of electrical long range charge transport.

摘要

在环境条件下以及在微加工的金属 - 绝缘体 - 金属间隙结构上的受控低湿度惰性气体气氛中，通过超灵敏低电流 - 电压光谱法（IV）研究了单个长λ噬菌体双链DNA分子的本征直流电导率。我们发现测量的电导率强烈依赖于表观湿度，我们将其归因于水在固定化DNA分子上的毛细管凝聚，从而产生额外的离子电流。在受控氩气气氛下的额外IV光谱实验总是显示电导率显著下降至4×10（-15）AV（-1）μm（-1），这表明电长程电荷传输几乎没有显著贡献。