Silver-coated eggshell membrane as a cost-effective SERS platform for enhanced molecular sensing.

Area of Science:

• Analytical Chemistry
• Materials Science
• Nanotechnology

Background:

• Surface-enhanced Raman spectroscopy (SERS) is crucial for sensitive molecular detection.
• Plasmonic substrates are essential for SERS signal enhancement.
• Developing cost-effective and efficient SERS substrates remains a key challenge.

Purpose of the Study:

• To fabricate a novel, low-cost SERS substrate using eggshell membrane (ESM) coated with silver (Ag).
• To investigate the effect of silver coating thickness on SERS performance.
• To evaluate the substrate's efficacy for detecting various Raman-active molecules.

Main Methods:

• Thermal evaporation of silver onto eggshell membrane to create ESM/Ag substrates.
• Systematic variation of silver coating thickness.
• SERS analysis of 4-mercaptobenzoic acid (4-MBA), 4-mercaptophenylboronic acid (4-MPBA), and rhodamine 6G (R6G).

Main Results:

• The ESM/Ag substrate demonstrated significant SERS activity with high Enhancement Factors (EFs).
• Optimal SERS performance was achieved with a silver deposition thickness of 20 nm.
• Improved sensitivity and lower detection limits were observed for all tested analytes.
• EFs achieved: 0.12 × 10⁶ for 4-MBA, 0.70 × 10⁵ for 4-MPBA, and 0.36 × 10⁴ for R6G.

Conclusions:

• Eggshell membrane serves as a viable, low-cost platform for fabricating high-performance SERS substrates.
• Precise control over silver coating thickness is critical for optimizing SERS enhancement.
• The developed ESM/Ag substrate is a promising, cost-effective solution for sensitive molecular sensing applications.