Passage times for polymer translocation pulled through a narrow pore

Area of Science:

• Polymer physics
• Statistical mechanics
• Soft matter physics

Background:

• Polymer translocation is crucial in biological processes like DNA and protein transport.
• Understanding translocation dynamics informs nanotechnology and biomaterial design.
• Previous studies established force-independent scaling at low forces.

Purpose of the Study:

• To investigate the effect of external force on polymer translocation time through a narrow pore.
• To elucidate the scaling behaviors of polymer passage time under varying forces.
• To identify the underlying polymer dynamics responsible for observed scaling.

Main Methods:

• Theoretical modeling of polymer dynamics during translocation.
• Analysis of polymer chain tension and memory effects near the pore.
• Derivation of scaling laws for passage time as a function of polymer length and applied force.

Main Results:

• At low forces (FN^nu/kBT < 1), passage time scales as N^(2+nu), independent of force.
• At high forces (FN^nu/kBT >> 1), passage time scales as N^2/F.
• Observed scaling behaviors are attributed to polymer dynamics and tension imbalance at the pore.

Conclusions:

• Polymer translocation dynamics exhibit distinct force-dependent regimes.
• Memory effects in polymer chain tension significantly influence passage times.
• The findings provide insights into controlling polymer transport through nanopores.