A pH-tunable nanofluidic diode with a broad range of rectifying properties

Area of Science:

• Nanotechnology
• Electrochemistry
• Biophysics

Background:

• Fixed charge nanopores require external tuning for versatile functions.
• Amphoteric materials offer tunable electrostatic interactions.
• Nanopore functionalization is key for advanced nanodevices.

Purpose of the Study:

• To design and characterize a single-track amphoteric nanopore with pH-sensitive charges.
• To demonstrate tunable ion rectification properties in a single nanodevice.
• To explore the potential of amphoteric nanopores in various applications.

Main Methods:

• Theoretical and experimental characterization of a conical nanopore.
• Functionalization with lysine and histidine chains to create amphoteric properties.
• pH-dependent analysis of electrostatic interactions and ion transport.

Main Results:

• The amphoteric nanopore exhibits pH-sensitive charge behavior.
• The nanofluidic diode demonstrates a broad range of tunable rectification properties.
• Structural asymmetry of the conical nanopore enhances functional versatility.

Conclusions:

• Amphoteric nanopores offer a single nanodevice solution for diverse rectification needs.
• These tunable nanopores have significant potential in drug delivery, separations, and sensing.
• Controlled functionalization of nanopores is crucial for advanced nanotechnological applications.