Nanochannels with Varied Outer Surface Charges for Protein Discrimination

Area of Science:

• Nanotechnology
• Biosensing
• Analytical Chemistry

Background:

• Solid-state nanochannels offer precise control over ion transport.
• Surface functionalization is key to developing selective biosensors.
• Ion rectification in nanochannels enables signal amplification and discrimination.

Purpose of the Study:

• To develop a novel nanochannel-based sensor for multiplexed protein detection.
• To utilize outer-surface functionalization for tunable ionic current modulation.
• To achieve sensitive and selective discrimination of multiple protein analytes.

Main Methods:

• Fabrication of asymmetrically charged solid-state nanochannels.
• Modification of nanochannel outer surfaces with DNA probes.
• Utilizing competitive binding of proteins to DNA probes for signal generation.
• Analysis of ionic current changes and ion rectification properties.

Main Results:

• Demonstrated effective spontaneous charge modulation and selective ionic current regulation.
• Achieved discrimination of six different proteins using a single type of DNA probe.
• Successfully distinguished proteins across various concentrations and in complex biological samples.
• Generated cross-reactive and differentiated ionic current signals for each target protein.

Conclusions:

• Outer-surface-functionalized nanochannels with asymmetric surface charge are effective for multianalyte discrimination.
• This approach offers a significant advancement in developing differential sensors for complex biological samples.
• The developed system shows promise for sensitive and selective protein detection in real-world applications.