Beckman Institute for Advanced Science and Technology, ‡Department of Electrical and Computer Engineering, and §Department of Physics, University of Illinois , Urbana, Illinois 61801, United States.
J Phys Chem B. 2017 Apr 20;121(15):3757-3763. doi: 10.1021/acs.jpcb.6b11040. Epub 2016 Dec 30.
We investigate theoretically the ability of graphene nanopore membranes to detect methylated sites along a DNA molecule by electronic sheet current along the two-dimensional (2D) materials. Special emphasis is placed on the detection sensitivity changes due to pore size, shape, position, and the presence of defects around the nanopore in a membrane with constricted geometry. Enhanced sensitivity for detecting methylated CpG sites, labeled by methyl-CpG binding domain (MBD) proteins along a DNA molecule, is obtained for electronic transport through graphene midgap states caused by the constriction. A large square deviation from the graphene conductance with respect to the open nanopore is observed during the translocation of MBD proteins. This approach exhibits superior resolution in the detection of multiple methylated sites along the DNA compared to conventional ionic current blockade techniques.
我们从理论上研究了石墨烯纳米孔膜通过二维（2D）材料中的电子面电流检测 DNA 分子上甲基化位点的能力。特别强调了由于孔尺寸、形状、位置以及在具有约束几何形状的膜中纳米孔周围存在缺陷而导致的检测灵敏度变化。通过石墨烯中场隙状态的电子输运，在 DNA 分子上通过甲基-CpG 结合域（MBD）蛋白标记的甲基化 CpG 位点的检测灵敏度得到增强，这种增强是由约束引起的。在 MBD 蛋白的易位过程中，观察到从石墨烯电导的大正方形偏差。与传统的离子电流阻断技术相比，这种方法在检测 DNA 上的多个甲基化位点方面具有更高的分辨率。
