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Determination of Zeta Potential via Nanoparticle Translocation Velocities through a Tunable Nanopore: Using DNA-modified Particles as an Example
Published on: October 26, 2016
Charge migration in DNA: ion-gated transport
R N Barnett1, C L Cleveland, A Joy
1School of Physics, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA.
Science (New York, N.Y.)
|October 20, 2001
Summary
Electron hole migration in DNA is controlled by hydrated counterions. Modifying DNA counterion bridges reduced hole mobility, confirming theoretical predictions and demonstrating a new method for controlling charge transport.
Area of Science:
- Biophysics
- Quantum Chemistry
- Molecular Biology
Background:
- Electron holes (radical cations) migrate in DNA via quantum transport.
- This transport is influenced by the dynamic motions of hydrated counterions.
Purpose of the Study:
- To investigate the role of counterion dynamics in DNA charge transport.
- To correlate counterion configurations with charge localization and migration.
- To experimentally validate theoretical predictions of reduced charge mobility.
Main Methods:
- Classical molecular dynamics simulations.
- Large-scale first-principles electronic structure calculations.
- Ultraviolet light-induced DNA cleavage experiments.
Main Results:
- Different counterion configurations lead to varied charge localization and spatial distributions.
- Stochastic fluctuations in counterion configurations induce correlated changes in hole distribution and transport.
- DNA with counterion-starved bridges showed reduced damage, indicating decreased hole mobility.
Conclusions:
- Counterion dynamics play a crucial role in gating electron hole migration in DNA.
- Theoretical models accurately predict the impact of counterion modifications on charge transport.
- Experimental results support the theoretical framework, showing reduced hole mobility in modified DNA structures.
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