Compression and free expansion of single DNA molecules in nanochannels.
We investigated compression and ensuing expansion of long DNA molecules confined in nanochannels. Transverse confinement of DNA molecules in the nanofluidic channels leads to elongation of their unconstrained equilibrium configuration. The extended molecules were compressed by electrophoretically driving them into porelike constrictions inside the nanochannels. When the electric field was turned off, the DNA strands expanded. This expansion, the dynamics of which has not previously been observable in artificial systems, is explained by a model that is a variation of de Gennes's polymer model.
School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA. hcf3@cornell.edu
Christian Hermann
CH
Reccius
John Thomas
JT
Mannion
Joshua David
JD
Cross
H G
HG
Craighead
D019245:Compressive Strength; D003198:Computer Simulation; D004247:DNA / Q000737:chemistry* / Q000648:ultrastructure*; D004548:Elasticity; D004586:Electrophoresis / Q000379:methods; D046210:Microfluidic Analytical Techniques / Q000379:methods*; D008846:Micromanipulation / Q000379:methods*; D008956:Models, Chemical; D008958:Models, Molecular; D036103:Nanotechnology / Q000379:methods*; D009690:Nucleic Acid Conformation; D013314:Stress, Mechanical
D004247:DNA