%0 Journal Article %J Phys Rev E Stat Nonlin Soft Matter Phys %D 2008 %T Electro-osmotic screening of the DNA charge in a nanopore %A Luan, Binquan %A Aleksei Aksimentiev %K DNA %K Models, Theoretical %K Nanostructures %K Osmosis %K Static Electricity %K Water %X

Extensive all-atom molecular dynamics simulations were performed to characterize the microscopic origin of the force experienced by DNA in a bulk electrolyte and a solid-state nanopore when subject to an external electrostatic field E. The effective screening of the DNA charge was found to originate from the hydrodynamic drag of the electro-osmotic flow that is driven by the motion of counterions along the surface of DNA. We show that the effective driving force F in a nanopore obeys the same law as in a bulk electrolyte: F=ximuE , where xi and mu are the friction coefficient and electrophoretic mobility of DNA, respectively. Using this relationship, we suggest a method for determining the effective driving force on DNA in a nanopore that does not require a direct force measurement.

%B Phys Rev E Stat Nonlin Soft Matter Phys %V 78 %P 021912 %8 2008 Aug %G eng %N 2 Pt 1