Solid-state nanopores are single-molecule sensors capable of analyzing individual unlabelled DNA molecules in solution. While the critical information obtained from nanopores is the signal collected during DNA translocation the throughput of the method, and in particular its ability to detect small amounts of biopolymers, are determined by the rate at which molecules arrive and thread (or captured) into the pores.

Our recent experimental and theoretical studies reveal that DNA capture by nanoscale pores is governed by a long range electrophoretic focusing effect, which leads to seemingly counter-intutive increase in the capture rate as a function of DNA length. Moreover, we show that the electro-focusing phenomenon opens the way to further increase the capture rate by orders of magnitude by manipulating the electrical potential near the nano-pore using salt gradients [1]. These discoveries mark an important milestone towards single-cell DNA analysis using the nanopores. 

[1] Wanunu M., W. Morrison, Y. Rabin, A.Y. Grosberg and A. Meller, Nature Nanotechnology 5, 160-165 (2010).