Trapped and non-trapped polymer translocations through a spherical pore

Area of Science:

• Polymer physics
• Nanopore technology
• Computational biophysics

Background:

• Polymer translocation through nanopores is a fundamental process with applications in DNA sequencing and drug delivery.
• Understanding the factors influencing translocation dynamics is crucial for optimizing these technologies.

Purpose of the Study:

• To investigate polymer translocation through a spherical pore using Langevin dynamics simulations.
• To classify translocation events into trapped and non-trapped categories and analyze their dependencies.
• To identify and characterize different pathways within trapped translocation events.

Main Methods:

• Langevin dynamics simulations were employed to model polymer translocation.
• Translocation events were classified based on whether the polymer became fully trapped in the pore.
• Key parameters investigated included polymer length, pore size, external voltage, and monomer-pore attraction.

Main Results:

• Trapped translocation events were found to be favored by larger pore sizes and lower external voltages.
• Monomer-pore attraction exhibited non-monotonic behavior on the probability of trapped translocation.
• Both trapped and non-trapped translocation times were dependent on polymer length, pore size, external voltage, and monomer-pore attraction.

Conclusions:

• The study identified two distinct pathways for trapped translocation: active and passive.
• Understanding these trapped pathways offers deeper insights into polymer translocation behavior.
• The findings provide a basis for controlling and manipulating polymer translocation in various applications.