Back to Search
Start Over
Electrokinetic stretching of tethered DNA.
- Source :
-
Biophysical journal [Biophys J] 2003 Oct; Vol. 85 (4), pp. 2539-46. - Publication Year :
- 2003
-
Abstract
- During electrophoretic separations of DNA in a sieving medium, DNA molecules stretch from a compact coil into elongated conformations when encountering an obstacle and relax back to a coil upon release from the obstacle. These stretching dynamics are thought to play an important role in the separation mechanism. In this article we describe a silicon microfabricated device to measure the stretching of tethered DNA in electric fields. Upon application of an electric field, electro-osmosis generates bulk fluid flow in the device, and a protocol for eliminating this flow by attaching a polymer brush to all silicon oxide surfaces is shown to be effective. Data on the steady stretching of DNA in constant electric fields is presented. The data corroborate the approximate theory of hydrodynamic equivalence, indicating that DNA is not free-draining in the presence of both electric and nonelectric forces. Finally, these data provide the first quantitative test of a Stigter and Bustamante's detailed theory of electrophoretic stretching of DNA without adjustable parameters. The agreement between theory and experiment is good.
- Subjects :
- Adsorption
DNA, Viral ultrastructure
Dose-Response Relationship, Radiation
Elasticity
Electric Stimulation methods
Kinetics
Models, Molecular
Nucleic Acid Conformation radiation effects
Physical Stimulation methods
Radiation Dosage
Spectrometry, Fluorescence
DNA, Viral chemistry
DNA, Viral radiation effects
Electromagnetic Fields
Electrophoresis methods
Microfluidics methods
Subjects
Details
- Language :
- English
- ISSN :
- 0006-3495
- Volume :
- 85
- Issue :
- 4
- Database :
- MEDLINE
- Journal :
- Biophysical journal
- Publication Type :
- Academic Journal
- Accession number :
- 14507716
- Full Text :
- https://doi.org/10.1016/S0006-3495(03)74676-1