Polymer translocation into a fluidic channel through a nanopore.

Area of Science:

• Polymer physics
• Soft matter physics
• Nanotechnology

Background:

• Polymer translocation is a fundamental process in biology and nanotechnology.
• Understanding polymer dynamics in confined geometries is crucial for various applications.
• Previous studies often simplified the translocation environment, neglecting crowding effects.

Purpose of the Study:

• To investigate the dynamics of polymer translocation into a fluidic channel through a nanopore.
• To analyze the influence of crowding effects and channel width on translocation time.
• To explore the relationship between translocation dynamics, driving force, and polymer length.

Main Methods:

• Utilizing two-dimensional Langevin dynamics simulations.
• Modeling polymer chains translocating through a nanopore into a confined fluidic channel.
• Varying channel diameter (R), driving force (F), and polymer chain length (N).

Main Results:

• Observed nonuniversal dependence of translocation time (τ) on chain length (N) due to crowding.
• Translocation time (τ) initially decreases rapidly and then saturates with increasing channel width (R).
• Scaling exponent (α) of τ with N depends on channel width (R); inverse linear scaling with F breaks down, showing a minimum.
• Observed behaviors are linked to the waiting time of individual segments passing through the pore.

Conclusions:

• Crowding effects significantly alter polymer translocation dynamics in confined channels.
• Channel width and driving force play critical roles in modulating translocation time and scaling behavior.
• The findings provide insights into the complex interplay of factors governing polymer transport in nanoscale systems.