A reduced graphene oxide based electrochemical biosensor for tyrosine detection

Area of Science:

• Materials Science
• Electrochemistry
• Biomedical Engineering

Background:

• Graphene oxide (GO) is a versatile nanomaterial with potential in biosensing.
• Developing sensitive and stable electrochemical biosensors is crucial for disease diagnosis.
• l-tyrosine is an important amino acid with implications in various physiological processes.

Purpose of the Study:

• To fabricate and characterize a hemin-modified graphene nanosheet (HGN) based electrochemical biosensor.
• To determine the efficacy of HGN biosensors for the detection of l-tyrosine.
• To evaluate the performance metrics including sensitivity, linear range, and stability.

Main Methods:

• Green hydrothermal reduction of graphene oxide to produce reduced graphene oxide (rGO).
• Immobilization of hemin onto rGO nanosheets via π-π interaction to form HGN.
• Fabrication of HGN modified glass carbon electrode (HGN/GCE) for electrochemical detection.
• Characterization using UV-Vis, fluorescence, FTIR, TGA, TEM, and EDX.
• Cyclic voltammetry for electrochemical analysis and performance evaluation.

Main Results:

• Successful immobilization of hemin on rGO confirmed by spectroscopic and microscopic analyses.
• HGN/GCE biosensor demonstrated a linear detection range for l-tyrosine from 5 × 10⁻⁷ M to 2 × 10⁻⁵ M.
• Achieved a low detection limit of 7.5 × 10⁻⁸ M with high sensitivity (133 times higher than bare GCE).
• The biosensor exhibited enhanced stability, a broader detection range, and superior sensitivity compared to other methods.

Conclusions:

• The developed HGN/GCE biosensor is a cost-effective, stable, and highly sensitive platform for l-tyrosine detection.
• Reduced graphene oxide enhances electron transfer, while hemin electrocatalyzes tyrosine oxidation.
• This nanomaterial-based biosensor holds promise for widespread clinical applications.