• Vesicle Prep Pro

    First product on the market for automated preparation of solvent-free giant unilamellar vesicles (GUVs)
  • Vesicle Prep Pro

    GUVs are homogeneous in size - ideal for different applications

2015 - Bilayer-Spanning DNA Nanopores with Voltage- Switching between Open and Closed State

Icon Orbit  Orbit 16 and   icon vpp   Vesicle Prep Pro publication in American Chemical Society Nano (2015)

Seifert A., Göpfrich K., Burns J.R., Fertig N., Keyser U.F., Howorka S.

ACS Nano (2015) 9(2):1117–1126


Membrane-spanning nanopores from folded DNA are a recent example of biomimetic man-made nanostructures that can open up applications in biosensing, drug delivery, and nanofluidics. In this report, we generate a DNA nanopore based on the archetypal six-helix-bundle architecture and systematically characterize it via single-channel current recordings to address several fundamental scientific questions in this emerging field. We establish that the DNA pores exhibit two voltage-dependent conductance states. Low transmembrane voltages favor a stable high-conductance level, which corresponds to an unobstructed DNA pore. The expected inner width of the open channel is confirmed by measuring the conductance change as a function of poly(ethylene glycol) (PEG) size, whereby smaller PEGs are assumed to enter the pore. PEG sizing also clarifies that the main ion-conducting path runs through the membrane-spanning channel lumen as opposed to any proposed gap between the outer pore wall and the lipid bilayer. At higher voltages, the channel shows a main low-conductance state probably caused by electric-field-induced changes of the DNA pore in its conformation or orientation. This voltage-dependent switching between the open and closed states is observed with planar lipid bilayers as well as bilayers mounted on glass nanopipettes. These findings settle a discrepancy between two previously published conductances. By systematically exploring a large space of parameters and answering key questions, our report supports the development of DNA nanopores for nanobiotechnology.

Download here

Back to Overview

Contact Us

Please type your full name.
Invalid email address.
Invalid Input
Invalid Input
Nanion Technologies GmbH

Ganghoferstr. 70A
D-80339 Munich - Germany