λ-DNA在锥形纳米孔中易位的研究  

Translocation of λ-DNA Through Solid-state Nanopore

作　　者：武灵芝[1] 瞿玲玉[1] 郭凌子[1] 史新卓[1] 

机构地区：[1]南京邮电大学地理与生物信息学院,江苏南京210023

出　　处：《南京邮电大学学报（自然科学版）》2013年第4期115-118,共4页Journal of Nanjing University of Posts and Telecommunications：Natural Science Edition

基　　金：国家自然科学基金青年项目(61101056);中国博士后科学基金(20110491339);东南大学生物电子学国家重点实验室开放课题(2011E14);南京邮电大学引进人才科研启动基金(NY210082)资助项目

摘　　要：纳米孔是目前单分子测序的一项重要技术,文中利用聚焦离子束在氮化硅薄膜上制备了30/60 nm的锥形孔,并通过膜片钳装置对λ-DNA易位的电学信号进行了统计和分析。发现在一定的电场(>200 mV)驱动下,DNA分子随着离子电流进入纳米孔,由于体积阻塞效应引起电流的下降。随着偏置电压的增大,阻塞电流也增大,同时易位的速度加快,DNA易位的弛豫时间减少。还可以根据阻塞信号的特点区分不同形貌的易位分子。Nanopores have become an important tool for molecule detection at single molecular level. Here,the conical nanopores were fabricated in silicon nitride （SiN） membrane by focused ion beam （FIB） technology. And the translocation of λ-DNA molecules through the prepared nanopores was charac- terized based on the ionic current obtained by patch clamp amplifier. Under the applied electric field （ 〉 200mV）, these macromoleeules was driven into the nanopore with the ionic current. A transient current decrease was observed due to the excluded volume of transition DNA in the background electrolyte. With the enhanced of driven voltages, the corresponding blockage current increased while the dwell time was decreased with the increase of the transition speed. Meanwhile, discrete folded types of DNA molecules passing through the pores were detected based on the multiple levels of blockade current signals.

关 键 词：纳米孔 DNA 偏置电压 阻塞电流 易位时间 

分 类 号：Q81[生物学—生物工程]