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Updated: Jan 28, 2026

Fine-tuning the Size and Minimizing the Noise of Solid-state Nanopores
Published on: October 31, 2013
Rapid and Accurate Determination of Nanopore Ionic Current Using a Steric Exclusion Model
James Wilson, Kumar Sarthak, Wei Si1
1Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments and School of Mechanical Engineering , Southeast University , Nanjing , 210096 , China.
A new Steric Exclusion Model (SEM) computational method accurately predicts nanopore sensing currents. This efficient approach, relating atomic geometry to ionic current, aids biomolecule detection and identification.
Area of Science:
- Biophysics
- Computational Biology
- Nanotechnology
Background:
- Nanopore sensing is crucial for biomolecule detection.
- Current methods for nanopore design rely on intuition.
- A computational method is needed to link nanopore/analyte geometry to current blockades.
Purpose of the Study:
- To develop a computationally efficient and accurate method for predicting nanopore conductance.
- To establish a link between atomic-scale pore and analyte geometry and ionic current blockades.
Main Methods:
- Developed the Steric Exclusion Model (SEM) for nanopore conductance.
- Combined finite element solver with nanopore conductance mapping.
- Validated SEM against all-atom molecular dynamics simulations.
Main Results:
- SEM is orders of magnitude more efficient than all-atom MD.
- SEM accurately predicts ionic current blockades for proteins, DNA, and amino acids.
- SEM accounts for atomic structure of nanopores and analytes.
Conclusions:
- SEM offers a robust, inexpensive, and accurate approach for nanopore sensing.
- SEM can guide nanopore design and analyte characterization.
- SEM is expected to be integral to future nanopore sensing development.
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