Fig 3.
Resistive-pulse sensing with two nanopores in series. (A) Two solid state pores are stacked in a pore-cavity-pore configuration for measuring DNA time-of-flight (TOF). A single event is shown on the right, where two pulses are observed for the transit of a single DNA strand, and the time between pulses is the transit time between pores. (B) Schematic of an in-plane nanochannel device with two pores in series fabricated in SiO2. Two pores measure the transit of single Hepatitis B Virus capsids, where each capsid is measured twice, as shown on the current trace on the right. Pulse amplitude (Δi) is proportional to capsid size, and the time between pulses (tpp) is used to calculate the electrophoretic mobility of the capsid. Panel A adapted with permission from Langecker et al.81 Copyright 2011 American Chemical Society. Panel B adapted with permission from Harms et al.82 Copyright 2011 American Chemical Society.