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Updated: Jun 27, 2026
11:55
Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
Published on: August 16, 2016
Control of ionic transport through gated single conical nanopores
Eric B Kalman1, Olivier Sudre, Ivan Vlassiouk
1Department of Physics and Astronomy, University of California, Irvine, CA, 92697, USA.
Analytical and Bioanalytical Chemistry
|December 18, 2008
Summary
Researchers developed an ionic transistor using nanoporous polymer films. Applying electric potential to a gold gate tunes ion transport from rectifying to linear behavior, enabling new device applications.
Area of Science:
- Nanotechnology
- Physical Chemistry
- Materials Science
Background:
- Controlling ionic transport in nanoporous systems is crucial for developing advanced devices.
- Existing nanoporous systems exhibit specific ion transport characteristics, such as rectification in conical pores.
Purpose of the Study:
- To demonstrate an ionic transistor capable of modulating ion transport behavior.
- To investigate the effect of an electric gate on ion transport in single nanopores.
Main Methods:
- Fabrication of polymer films with single conical nanopores.
- Integration of an insulated gold thin film gate electrode.
- Measurement of ionic current through the nanopore under varying gate potentials.
Main Results:
- The ionic transistor successfully altered ion transport characteristics.
- Switching from rectifying to linear current-voltage behavior was observed by adjusting the gate potential.
- The observed changes were attributed to gate-induced enhancement of concentration polarization.
Conclusions:
- An ionic transistor based on a single conical nanopore with a gate electrode was successfully prepared.
- The gate effectively controlled ionic transport, transitioning behavior from rectifying to linear.
- This demonstrates a novel method for tunable ion transport in nanoporous devices.
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01:24Non-gated Ion Channels
Ion channels are specialized proteins on the plasma membrane that allow charged ions to pass down their electrochemical gradient. Their main function is to maintain the membrane potential which is critical for cell viability. These channels are either gated or non-gated and can transport more than a thousand ions within milliseconds for the cellular event to occur.
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
01:24Non-gated Ion Channels
Ion channels are specialized proteins on the plasma membrane that allow charged ions to pass down their electrochemical gradient. Their main function is to maintain the membrane potential which is critical for cell viability. These channels are either gated or non-gated and can transport more than a thousand ions within milliseconds for the cellular event to occur.
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
01:19Ion Channels
The movement of ions like sodium, potassium, and calcium into and out of the cell is essential to maintain the electrochemical gradient in living cells. The ion channels—a class of membrane transport proteins—help maintain this ionic gradient for the smooth functioning of physiological activities such as maintaining cell size and volume, conducting nerve impulses, and gas and nutrient exchange.
Ion channels are specialized integral membrane proteins on the plasma membrane that allow specific...
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