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Updated: May 12, 2026

Monitoring Protein Adsorption with Solid-state Nanopores

Monitoring Protein Adsorption with Solid-state Nanopores

Published on: December 2, 2011

Free-energy measuring nanopore device.

Momčilo Gavrilov¹, Jinghang Zhang², Olivia Yang¹

¹Johns Hopkins University School of Medicine, Department of Biophysics and Biophysical Chemistry, 725 N. Wolfe Street, Baltimore, Maryland 21205, USA.

Physical Review. E

|March 16, 2024

Summary

This summary is machine-generated.

Nanopores offer a novel method for measuring molecular free energies (FEs) by analyzing DNA hairpin unfolding. This technique overcomes equilibrium sampling challenges, providing accurate FE estimates comparable to optical tweezers.

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Area of Science:

Molecular Biophysics
Nanotechnology
Thermodynamics

Background:

Free energies (FEs) quantify molecular stability.
Single-molecule pulling experiments are crucial for measuring FEs.
Equilibrium sampling is a persistent challenge in these experiments.

Purpose of the Study:

Introduce nanopores as a tool for measuring free energies.
Compare nanopore measurements with optical tweezers.
Investigate the impact of sampling methods on FE estimates.

Main Methods:

Pulling DNA hairpin-forming molecules through a nanopore.
Measuring work and applying the Jarzynski fluctuation theorem (FT).
Comparing nanopore results with optical tweezer experiments.

Main Results:

Nanopores accurately estimate FE changes in both slow and fast pulling regimes.
The FT enables FE estimation at fast pulling times.
Nanopore and optical tweezer FE estimates agree when molecules are sampled from equilibrium.

Conclusions:

Nanopores provide a robust method for measuring molecular free energies.
This technique addresses the critical issue of equilibrium sampling in single-molecule experiments.
Nanopores are valuable for comparing FEs of different molecules at finite times.