Enzyme-immobilized graphene oxide-based electrochemical biosensor for glutathione detection

Area of Science:

• Biomedical Engineering
• Electrochemistry
• Materials Science

Background:

• Glutathione is a vital antioxidant, and its depletion indicates oxidative stress.
• Developing sensitive methods for glutathione detection is crucial for health monitoring.

Purpose of the Study:

• To develop a sensitive electrochemical sensor for glutathione detection.
• To utilize laccase enzyme immobilized on graphene oxide (GO) for enhanced sensing capabilities.

Main Methods:

• Indium tin oxide (ITO) electrode surface modified with GO via drop casting.
• Immobilization of laccase enzyme onto the GO-modified ITO surface.
• Characterization using FESEM, XPS, FTIR, CV, and EIS; electrochemical detection of glutathione (GSH).

Main Results:

• FTIR, FESEM, and Raman analyses confirmed successful laccase immobilization on GO.
• The laccase/GO/ITO electrode demonstrated enhanced electrocatalytic activity for GSH oxidation.
• Achieved a wide linear range (1 μM–100 μM), low limit of detection (0.89 μM), and high sensitivity (6.51 μA μM⁻¹).

Conclusions:

• The developed electrochemical sensor offers high sensitivity, selectivity, repeatability, and stability for glutathione detection.
• The sensor successfully detected GSH in real samples, demonstrating practical applicability.
• This approach provides a promising tool for assessing oxidative stress through glutathione level monitoring.