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Fine-tuning the Size and Minimizing the Noise of Solid-state Nanopores
Published on: October 31, 2013
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Up and down translocation events and electric double-layer formation inside solid-state nanopores
Mehdi B Zanjani1, Rebecca E Engelke2, Jennifer R Lukes1
1Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 19, 2015
Summary
This study reveals nanorod translocation through nanopores causes ion conductance changes. The sign of the change depends on nanopore size, enabling nanorod detection.
Area of Science:
- Physics
- Materials Science
- Nanotechnology
Background:
- Nanorod translocation through solid-state nanopores is a key phenomenon in nanoscale sensing.
- Ion conductance changes during translocation are complex and depend on various factors.
Purpose of the Study:
- To theoretically investigate nanorod translocation events through solid-state nanopores of varying sizes.
- To elucidate the physics governing ion conductance changes (positive or negative).
- To develop a method for distinguishing nanorods based on conductance change sign.
Main Methods:
- Theoretical modeling of nanorod translocation dynamics.
- Analysis of ion conductance changes in relation to nanopore diameter.
- Investigation of electric double-layer effects in small nanopores.
- Development of a geometric model for nanoparticle blockade in large nanopores.
Main Results:
- Positive conductance changes (up events) occur for nanopore diameters smaller than a transition diameter (dt).
- Negative conductance changes (down events) occur for nanopore diameters larger than dt.
- A geometric model accurately predicts ion conductance change for large nanopores.
- A method to distinguish nanorod sizes based on conductance change sign was implemented.
Conclusions:
- The sign of ion conductance change during nanorod translocation is a critical indicator of nanopore size relative to a transition diameter.
- Electric double-layer effects are significant for small nanopores, while geometric blockade dominates in larger ones.
- Focusing on the sign of conductance change provides a robust method for nanorod size discrimination and detection.
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