Enzyme-modified nanoporous gold-based electrochemical biosensors

Area of Science:

• Electrochemistry
• Nanomaterials Science
• Biosensor Technology

Background:

• Nanoporous gold (NPG) possesses unique physical and chemical properties.
• NPG is synthesized by dealloying silver (Ag) from gold/silver (Au/Ag) alloys.
• Electrochemical biosensors are crucial for various analytical applications.

Purpose of the Study:

• To develop novel electrochemical biosensors utilizing nanoporous gold (NPG).
• To investigate the electrocatalytic activity of NPG-modified electrodes.
• To assess the performance of NPG-based biosensors for ethanol and glucose detection.

Main Methods:

• Fabrication of NPG-modified glassy carbon electrodes (NPG/GCE).
• Electrochemical characterization of NPG/GCE for NADH and H2O2 oxidation.
• Immobilization of alcohol dehydrogenase (ADH) and glucose oxidase (GOD) onto NPG.
• Amperometric detection of ethanol and glucose at low potentials.

Main Results:

• NPG/GCE demonstrated high electrocatalytic activity, reducing overpotential for NADH and H2O2 oxidation.
• The high density of defect sites and large surface area of NPG contribute to its electrocatalytic properties.
• NPG-based biosensors exhibited excellent analytical performance for ethanol and glucose.
• The biosensors showed remarkable stability, retaining over 95% of their response after one month.

Conclusions:

• Nanoporous gold is a promising electrode material for constructing stable and efficient electrochemical biosensors.
• The unique microstructure and properties of NPG enhance biosensor performance.
• NPG facilitates low-potential amperometric detection of important analytes like ethanol and glucose.