Voltage-driven translocation: Defining a capture radius.

Area of Science:

• Nanopore science
• Analytical chemistry
• Physical chemistry

Background:

• Analyte translocation through nanopores involves diffusion, capture, and threading.
• The capture phase is poorly understood due to visualization and measurement challenges.
• Existing models for capture radius (R*) are often ambiguous and oversimplified.

Purpose of the Study:

• To investigate methods for defining and estimating the capture radius (R*) in nanopore devices.
• To analyze the influence of electric fields and diffusion on analyte capture dynamics.
• To address ambiguities in current R* definitions and models.

Main Methods:

• Theoretical analysis of the Péclet number.
• Monte Carlo simulations with varied protocols.
• Investigation of charged particle diffusion and electric field attraction to nanopores.

Main Results:

• The study reveals that R* estimation is sensitive to boundary conditions.
• Pore size and finite experimental durations significantly impact R* interpretation.
• Péclet number analysis provides a framework for understanding capture dynamics.

Conclusions:

• A more rigorous definition and estimation of R* are needed for accurate nanopore device characterization.
• Factors like boundary conditions, pore size, and experimental time must be considered.
• This work provides a foundation for improved modeling of nanopore analyte capture.