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Diffusional motion of a particle translocating through a nanopore
1Department of Chemistry, University of Utah, 315 S 1400 E, Salt Lake City, Utah 84112, United States.
ACS Nano
|January 4, 2012
Summary
Diffusional motion influences nanoparticle capture and release through nanopores. The study shows particle translocation sequences are preserved during pressure reversal, enabling particle analysis.
Area of Science:
- Nanotechnology
- Physical Chemistry
- Materials Science
Background:
- Understanding nanoparticle behavior in confined geometries is crucial for developing advanced materials and sensing technologies.
- Pressure-induced flow through nanopores is a key mechanism for manipulating and analyzing nanoparticles.
- Diffusional motion introduces stochasticity into nanoparticle trajectories, impacting capture and release dynamics.
Purpose of the Study:
- To investigate the influence of diffusional motion on nanoparticle capture and release through a conical glass nanopore membrane (GNM).
- To analyze the sequence preservation of nanoparticle translocations during pressure-induced flow and reversal.
- To explore the application of the pressure-reversal technique for particle analysis using resistive-pulse methods.
Main Methods:
- Utilizing a conical-shaped glass nanopore membrane (GNM) for nanoparticle translocation experiments.
- Employing pressure-induced flow to drive nanoparticles through the nanopore.
- Applying the resistive-pulse technique to monitor temporal sequences of particle capture and release.
- Investigating stochastic influences of diffusion on particle trajectories, including transfer rate and release probability.
Main Results:
- Demonstrated that the sequence of nanoparticle translocations during capture is largely preserved during release after pressure reversal.
- Showed that particle size (120-160 nm) and translocation direction can be determined from resistive-pulse signatures.
- Observed stochastic events align well with a convective diffusion model for particle trajectories within the nanopore.
Conclusions:
- Diffusional motion significantly impacts nanoparticle capture and release dynamics in nanopores.
- The pressure-reversal technique, combined with resistive-pulse sensing, allows for the readout of nanoparticle translocation sequences.
- This method offers new possibilities for chemical analysis of particles using resistive-pulse techniques.
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