Surface plasmon resonance biosensor based on Hg/Ag-Au film

Area of Science:

• Electrochemistry
• Biosensing Technology
• Surface Science

Background:

• Surface Plasmon Resonance (SPR) biosensors are crucial for biomolecular detection.
• Modifying gold (Au) surfaces with other metals can enhance SPR sensitivity.
• Electrodeposition offers a controlled method for creating metal alloy films.

Purpose of the Study:

• To investigate the effect of electrodeposited mercury (Hg) and silver (Ag) on gold (Au) surfaces for SPR biosensing.
• To compare the sensitivity of Hg-Au and Ag-Au SPR biosensors for human and rabbit immunoglobulin G (IgG) detection.
• To determine the optimal metal deposition for enhanced IgG quantification.

Main Methods:

• Fabrication of Hg-Au and Ag-Au films via electrodeposition onto an Au surface.
• Utilizing wavelength-modulation SPR biosensors for direct immunoassay.
• Quantifying human and rabbit IgG concentrations across different sensing surfaces.

Main Results:

• SPR biosensors with Hg-Au films showed improved detection ranges for human IgG (0.50-40.00 µg/ml) and rabbit IgG (0.63-40.00 µg/ml).
• SPR biosensors with Ag-Au films demonstrated significantly enhanced sensitivity, with detection ranges of 0.25-20.00 µg/ml (human IgG) and 0.42-20.00 µg/ml (rabbit IgG).
• The Ag-Au biosensor exhibited up to an eight-fold increase in sensitivity compared to the bare Au biosensor.

Conclusions:

• Electrodeposition of Ag onto an Au surface creates a highly sensitive SPR biosensor.
• The Ag-Au SPR biosensor offers superior performance for the determination of human and rabbit IgG.
• This Ag-Au film approach represents a significant advancement in SPR-based immunoassay sensitivity.