Surface charge modulated aptasensor in a single glass conical nanopore.

Area of Science:

• Biotechnology
• Nanotechnology
• Biosensing

Background:

• Label-free biosensing is crucial for efficient protein detection.
• Nanopore technology offers a platform for single-molecule analysis.
• Developing selective and sensitive protein detection methods remains a challenge.

Purpose of the Study:

• To develop a label-free nanopore-based biosensing strategy for protein detection.
• To utilize DNA-protein interactions within a single glass conical nanopore.
• To demonstrate the potential for broad application in protein biosensing.

Main Methods:

• Functionalization of a glass nanopore with lysozyme binding aptamer (LBA) via siloxane chemistry.
• Generation of negatively charged recognition sites within the nanopore.
• Monitoring protein-ligand interactions via changes in ionic current and current-voltage (I-V) characteristics.

Main Results:

• Successful covalent modification of the nanopore with LBA.
• Demonstration of sensitive current changes upon lysozyme binding due to charge neutralization.
• Exhibited excellent selectivity and sensitivity towards the target protein (lysozyme).

Conclusions:

• The proposed method provides a label-free, highly sensitive, and selective approach for protein detection.
• The charge modulation mechanism within the nanopore is effective for biosensing.
• This strategy can be extended to develop biosensing platforms for various proteins.