Nanopore devices have attracted a lot of attention for their potential application in DNA sequencing. Here, we study how an occluding object placed near a nanopore affects its access resistance by integrating an atomi...Nanopore devices have attracted a lot of attention for their potential application in DNA sequencing. Here, we study how an occluding object placed near a nanopore affects its access resistance by integrating an atomic force microscopy with a nanopore sensor. It is found that there exists a critical hemisphere around the nanopore, inside which the tip of an atomic force microscopy will affect the ionic current. The radius of this hemisphere, which is a bit smaller than the theoretical capture radius of ions, increases linearly with the applied bias voltage and quadratically with the nanopore diameter, but is independent of the operation modes and scanning speeds of the atomic force microscopy. A theoretical model is also proposed to describe how the tip position and geometrical parameters affect the access resistance.展开更多
基金supported by the National Natural Science Foundation of China(Grants Nos.51435003&51375092)supported by the Fundamental Research Funds for the Central Universities+1 种基金the Innovative Project for Graduate Students of Jiangsu Province(Grant No.KYLX_0100)the Scientific Research Foundation of Graduate School of Southeast University(Grant No.YBJJ1540)
文摘Nanopore devices have attracted a lot of attention for their potential application in DNA sequencing. Here, we study how an occluding object placed near a nanopore affects its access resistance by integrating an atomic force microscopy with a nanopore sensor. It is found that there exists a critical hemisphere around the nanopore, inside which the tip of an atomic force microscopy will affect the ionic current. The radius of this hemisphere, which is a bit smaller than the theoretical capture radius of ions, increases linearly with the applied bias voltage and quadratically with the nanopore diameter, but is independent of the operation modes and scanning speeds of the atomic force microscopy. A theoretical model is also proposed to describe how the tip position and geometrical parameters affect the access resistance.
