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Published on: December 29, 2015
DNA electrophoresis in microfluidic post arrays under moderate electric fields
1Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, Minnesota 55455, USA. dorfman@cems.umn.edu
Summary
This study models DNA in microfluidics using a continuous-time random walk. The stem-flower conformation of DNA impacts its movement and separation resolution in microfluidic devices.
Area of Science:
- Biophysics
- Physical Chemistry
- Nanotechnology
Background:
- Understanding DNA dynamics in microfluidic systems is crucial for advanced separation technologies.
- Previous models often simplify polymer behavior, neglecting complex conformations.
Purpose of the Study:
- To develop a microscale model for long DNA dynamics in microfluidic post arrays under electric fields.
- To investigate the influence of DNA conformation on its transport and separation efficiency.
Main Methods:
- A Scher-Lax continuous-time random walk model was employed.
- The model incorporates polymer collision, unhooking, and translation steps with random variables.
- Analytical expressions for mean velocity and dispersivity were derived.
Main Results:
- The stem-flower conformation reduces DNA's engagement time with posts and increases collision frequency.
- Incomplete chain extension increases dispersivity compared to a taut chain.
- Model predictions show good agreement with experimental data without adjustable parameters.
Conclusions:
- The developed model accurately describes DNA dynamics in microfluidics.
- The stem-flower conformation plays a significant role in DNA transport and separation resolution.
- The findings support the use of microfluidic devices for DNA analysis.
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