DNA confined in nanochannels: hairpin tightening by entropic depletion.

  title={DNA confined in nanochannels: hairpin tightening by entropic depletion.},
  author={Theo Odijk},
  journal={The Journal of chemical physics},
  volume={125 20},
  • T. Odijk
  • Published 2 October 2006
  • Physics, Chemistry
  • The Journal of chemical physics
A theory is presented of the elongation of double-stranded DNA confined in a nanochannel based on a study of the formation of hairpins. A hairpin becomes constrained as it approaches the wall of a channel which leads to an entropic force causing the hairpin to tighten. The DNA in the hairpin remains double-stranded. The free energy of the hairpin is significantly larger than what one would expect if this entropic effect were unimportant. As a result, the distance between hairpins or the global… 

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