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Updated: Feb 6, 2026
08:51
Monitoring Protein Adsorption with Solid-state Nanopores
Published on: December 2, 2011
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Gating Protein Transport in Solid State Nanopores by Single Molecule Recognition
Gustav Emilsson1, Yusuke Sakiyama2, Bita Malekian1
1Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Göteborg, Sweden.
ACS Central Science
|August 31, 2018
Summary
Researchers developed a new method to control molecular flow through nanopores using antibody-gated poly(ethylene glycol) brushes. This breakthrough enables dynamic control over nanoscale barriers for biomolecular separation and analysis.
Area of Science:
- Nanotechnology
- Biomolecular Engineering
- Surface Science
Background:
- Controlling molecular translocation through nanoscale apertures is crucial for applications like DNA sequencing and biomolecular filtration.
- Existing methods for regulating nanopore permeability are significantly limited, hindering advancements in single-molecule analysis.
- Poly(ethylene glycol) (PEG) brushes are effective in preventing protein translocation through nanopores.
Purpose of the Study:
- To develop a novel method for dynamically controlling nanopore permeability.
- To investigate the use of antibody binding to reversibly gate nanopores functionalized with PEG brushes.
- To explore new possibilities for biomolecular separation and analysis using nanoscale dynamic barriers.
Main Methods:
- Functionalization of nanopores with poly(ethylene glycol) brushes to create a protein-repellent barrier.
- Utilizing single IgG antibodies to reversibly disrupt the macromolecular barrier and gate the nanopores.
- Employing surface plasmon resonance (SPR) for kinetic analysis of antibody-polymer interactions.
- Validation using fluorescence readout from pore arrays and high-speed atomic force microscopy (HS-AFM) on individual pores.
Main Results:
- Nanopores functionalized with PEG brushes effectively prevent protein translocation.
- Binding of single IgG antibodies can reversibly open the nanopores by disrupting the PEG brush barrier.
- A two-state model explains the kinetics of antibody-polymer interaction, distinguishing between reversibly and irreversibly bound antibodies.
- Reversibly bound antibodies reduce protein exclusion height, while irreversibly bound antibodies do not.
Conclusions:
- Dynamic control of nanoscale barriers is achievable through antibody-gated polymer brushes.
- This approach offers a new platform for precise biomolecular separation and analysis.
- The findings pave the way for advanced applications in molecular diagnostics and nanotechnology.
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