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Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Sorting by diffusion: an asymmetric obstacle course for continuous molecular separation
C F Chou1, O Bakajin, S W Turner
1Department of Physics, Princeton University, Princeton, NJ 08544, USA.
Summary
This study introduces a microfabricated sieve for DNA separation, utilizing Brownian motion rectification. This continuous flow technique offers an alternative to traditional batch-mode gel electrophoresis for DNA analysis.
Area of Science:
- Biophysics
- Nanotechnology
- Molecular Biology
Background:
- Traditional DNA separation methods like gel electrophoresis operate in batch mode.
- Analyzing DNA molecule motion requires precise control and high resolution.
- Brownian motion presents challenges for controlled molecular manipulation.
Purpose of the Study:
- To demonstrate a novel microfabricated sieve for separating DNA molecules based on size.
- To investigate the rectification of Brownian motion for size-dependent molecular trajectories.
- To establish a continuous-flow separation technique for DNA analysis.
Main Methods:
- Fabrication of a microfluidic device with a two-dimensional lattice of asymmetric obstacles.
- Observing the motion of different-sized DNA molecules (15-30 kbp) through the sieve.
- Utilizing Brownian motion driven by an external force to direct molecular paths.
Main Results:
- Demonstrated successful separation of DNA molecules by size using the microfabricated sieve.
- Achieved a nominal 6% resolution by length for DNA molecules in the 15-30 kbp range.
- Validated that molecular path depends on diffusion coefficient, influenced by obstacle arrangement.
Conclusions:
- The microfabricated sieve offers a continuous-flow method for DNA separation.
- This technique provides an advancement over batch-mode gel electrophoresis.
- The device shows potential for high-throughput, size-based DNA analysis.
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