A practical method to fabricate gold substrates for surface-enhanced Raman spectroscopy

Area of Science:

• Materials Science
• Spectroscopy
• Nanotechnology

Background:

• Surface-enhanced Raman spectroscopy (SERS) requires specialized substrates for sensitive chemical detection.
• Current methods for SERS substrate fabrication can be time-consuming and inconsistent.

Purpose of the Study:

• To develop a practical and reproducible method for fabricating SERS substrates using commercially available materials.
• To evaluate the performance and consistency of the newly developed SERS substrates.

Main Methods:

• Dip-coating poly-L-lysine derivatized microscope slides in a gold colloidal suspension.
• Characterization of colloid deposition using scanning electron microscopy (SEM).
• Evaluation of SERS performance and reproducibility using Rhodamine 6G and Isoniazid.

Main Results:

• Successful fabrication of SERS substrates with performance comparable to traditional methods.
• Demonstrated reproducibility across multiple substrate locations with low variability (<10% RSD for some peaks).
• Observed differential susceptibility of spectral peaks to variability, linked to chemisorption and local enhancement effects.

Conclusions:

• The dip-coating method provides a practical, time-efficient, and reproducible approach to SERS substrate fabrication.
• The developed substrates exhibit reliable SERS performance for chemical detection.
• Understanding spectral variability aids in optimizing SERS analysis and interpreting results.