Collapse of DNA under alternating electric fields.
Recent studies have shown that double-stranded DNA can collapse in the presence of a strong electric field. Here we provide an in-depth study of the collapse of DNA under weak confinement in microchannels as a function of buffer strength, driving frequency, applied electric-field strength, and molecule size. We find that the critical electric field at which DNA molecules collapse (tens of kV/m) is strongly dependent on driving frequency (100-800 Hz) and molecular size (20-160 kbp), and weakly dependent on the ionic strength (8-60 mM). We argue that an apparent stretching at very high electric fields is an artifact of the finite frame time of video microscopy.
Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202, USA.
Chunda
C
Zhou
Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202, USA.
Robert
R
Riehn
D004247:DNA / Q000737:chemistry*; D059018:DNA Contamination; D055590:Electromagnetic Phenomena; D007477:Ions / Q000737:chemistry; D008856:Microscopy, Fluorescence; D014741:Video Recording
D007477:Ions; D004247:DNA