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Flowing fluid past chiral objects has been used for centuries to power rotary motion in man-made machines. By contrast, rotary motion in nanoscale biological or chemical systems is produced by biasing Brownian motion through cyclic chemical reactions. Here we show that a chiral biological molecule, a DNA or RNA duplex rotates unidirectionally at billions of revolutions per minute when an electric field is applied along the duplex, with the rotation direction being determined by the chirality of the duplex. The rotation is found to be powered by the drag force of the electro-osmotic flow, realizing the operating principle of a macroscopic turbine at the nanoscale. The resulting torques are sufficient to power rotation of nanoscale beads and rods, offering an engineering principle for constructing nanoscale systems powered by electric field.
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This content will become publicly available on September 1, 2027
DNA: A NanoscaleArchimedes’ Screw
Abstract Rotating helices have been utilized for many purposes, including the transport of solid material and fluids within man-made machines for a little over two millennia. Here, we show that the rotation of a biological helical molecule─a DNA duplex─can move water and ions through a nanoscale pore. While the rotation-induced flow of water is generated by the steric shape of the DNA molecule, an even faster transport of cations is caused by electrostatic interactions. The rotation-induced ion flux is found to depend on the cation type, offering potential utility for ion separation. Finally, we show that the torque-driven duplex can move ions against a concentration gradient, realizing the Archimedes screw principle at the nanoscale.
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- Award ID(s):
- 2411133
- PAR ID:
- 10712208
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Nano Letters
- ISSN:
- 1530-6984
- Subject(s) / Keyword(s):
- DNA nanotechnology, nanopores, ion pump, filtration, molecular dynamics, nanofluidics
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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