Detection and analysis of DNA recapture through a solid-state nanopore  

作　　者：Ying Hu Zhi Zhou Xinyan Shan Xinghua Lu 

机构地区：[1]Institute of Physics,Chinese Academy of Sciences [2]Collaborative Innovation Center of Quantum Matter

出　　处：《Chinese Science Bulletin》2014年第35期4953-4959,共7页

基　　金：supported by the National Basic Research Program of China(2012CB933002);Strategic Priority Research Program(B)of the Chinese Academy of Sciences(XDB07030100);the financial aid from Open Research Fund Program of the State Key Laboratory of Low Dimensional Quantum Physics(KF201201);the support of Hundred Talent Program of Chinese Academy of Sciences

摘　　要：Motion control of a single molecule through a solid-state nanopore offers a new perspective on detecting and analyzing single biomolecules.Repeat recapture of a single DNA molecule reveals the dynamics in DNA translocation through a nanopore and may significantly increase the signal-to-noise ratio for DNA base distinguishing.However,the transient current at the moment of voltage reversal prevents the observation of instantly recaptured molecules and invalidates the continuous DNA ping-pong control.We performed and analyzed the DNA translocation and recapture experiment in a silicon nitride solid-state nanopore.Numerical calculation of molecular motion clearly shows the recapture dynamics with different delay times.The prohibited time when the data acquisition system is saturated by the transient current is derived by equivalent circuit analysis and finite element simulation.The COMSOL simulation reveals that the membrane capacitance plays an important role in determining the electric field distribution during the charging process.As a result of the transient charging process,a non-constant driving force pulls the DNA back to nanopores faster than theoretically predicted.The observed long time constant in the transient current trace is explained by the dielectric absorption of the membrane capacitor.Motion control of a single molecule through a solid-state nanopore offers a new perspective on detecting and analyzing single biomolecules. Repeat recapture of a single DNA molecule reveals the dynamics in DNA translocation through a nanopore and may significantly increase the signal-to-noise ratio for DNA base distin- guishing. However, the transient current at the moment of voltage reversal prevents the observation of instantly recaptured molecules and invalidates the continuous DNA ping-pong control. We performed and analyzed the DNA translocation and recapture experiment in a silicon nitride solid-state nanopore. Numerical calculation of molecular motion clearly shows the recapture dynamics with different delay times. The prohibited time when the data acquisition system is saturated by the transient current is derived by equivalent circuit analysis and finite element simulation. The COMSOL simulation reveals that the membrane capacitance plays an important role in determining the electric field distribution during the charging process. As a result of the transient charging process, a non-constant driving force pulls the DNA back to nanopores faster than theoretically predicted. The observed long time constant in the transient current trace is explained by the dielectric absorption of the membrane capacitor.

关 键 词：单个DNA分子 纳米孔 固态 检测 瞬态电流 数据采集系统 生物分子 运动控制 

分 类 号：Q523[生物学—生物化学] TB383.1[一般工业技术—材料科学与工程]