Bonthuis Douwe Jan, Zhang Jingshan, Hornblower Breton, Mathé Jérôme, Shklovskii Boris I, Meller Amit
Department of Physics and Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA.
Phys Rev Lett. 2006 Sep 22;97(12):128104. doi: 10.1103/PhysRevLett.97.128104. Epub 2006 Sep 21.
The current-voltage characteristics of the alpha-Hemolysin protein pore during the passage of single-stranded DNA under varying ionic strength C are studied experimentally. We observe strong blockage of the current, weak superlinear growth of the current as a function of voltage, and a minimum of the current as a function of C. These observations are interpreted as the result of the ion electrostatic self-energy barrier originating from the large difference in the dielectric constants of water and the lipid bilayer. The dependence of DNA capture rate on C also agrees with our model.
实验研究了在不同离子强度C下，单链DNA通过α-溶血素蛋白孔时的电流-电压特性。我们观察到电流出现强烈阻塞、电流随电压呈弱超线性增长以及电流随C出现最小值。这些观察结果被解释为源于水和脂质双层介电常数巨大差异的离子静电自能垒的结果。DNA捕获率对C的依赖性也与我们的模型相符。
