Nafion coated nanopore electrode for improving electrochemical aptamer-based biosensing

Area of Science:

• Electrochemistry
• Nanotechnology
• Biomedical Engineering

Background:

• Personalized point-of-care medicine requires advanced diagnostic tools.
• Electrochemical aptamer biosensors offer target specificity but face signal and biofouling challenges.
• Nanostructured electrodes and protective coatings can improve biosensor performance.

Purpose of the Study:

• To develop and characterize a Nafion-coated gold nanoporous electrode for aptamer-based biosensing.
• To investigate the effect of Nafion coating on biosensor performance in complex environments.
• To elucidate the signaling mechanism of aptamers within nanoporous structures.

Main Methods:

• Fabrication of gold nanoporous electrodes using sputtering and dealloying.
• Immobilization of structure-switching aptamers within nanopores.
• Coating with Nafion, an ion-exchange membrane, while excluding it from nanopores.
• Optimization of aptamer density, Nafion thickness, and nanopore size.
• Electrochemical characterization and analysis of signaling behavior.

Main Results:

• Successfully created Nafion-coated gold nanoporous electrodes with controlled nanopore sizes.
• Demonstrated enhanced signal-to-noise ratio and anti-biofouling properties.
• Optimized biosensor parameters for improved detection.
• Proposed a mechanism for the unique aptamer signaling within nanopores.

Conclusions:

• Nafion-coated nanoporous electrodes provide a robust platform for aptamer-based biosensors.
• This approach addresses key challenges in miniaturized biosensing for point-of-care applications.
• The study offers a generalizable method for developing advanced membrane-coated aptamer biosensors.