It is now possible to slow and trap a single molecule of double-stranded DNA (dsDNA), by stretching it using a nanopore, smaller in diameter than the double helix, in a solid-state membrane. By applying an electric force larger than the threshold for stretching, dsDNA can be impelled through the pore. Once a current blockade associated with a translocating molecule is detected, the electric field in the pore is switched in an interval less than the translocation time to a value below the threshold for stretching. According to molecular dynamics (MD) simulations, this leaves the dsDNA stretched in the pore constriction with the base-pairs tilted, while the B-form canonical structure is preserved outside the pore. In this configuration, the translocation velocity is substantially reduced from 1 bp/10 ns to ∼1 bp/2 ms in the extreme, potentially facilitating high fidelity reads for sequencing, precise sorting, and high resolution (force) spectroscopy.
|Original language||English (US)|
|State||Published - Oct 1 2010|
ASJC Scopus subject areas
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering
- Electrical and Electronic Engineering