Disposable, stable media for reproducible surface-enhanced Raman spectroscopy

Area of Science:

• Materials Science
• Analytical Chemistry
• Spectroscopy

Background:

• Developing stable and reproducible surface-enhanced Raman spectroscopy (SERS) media is crucial for sensitive chemical analysis.
• Existing SERS substrates can be expensive or lack long-term stability, limiting their practical application.
• The need for disposable, cost-effective SERS-active materials for routine analysis is growing.

Purpose of the Study:

• To develop a method for preparing identical, stable, and inexpensive SERS-active media.
• To demonstrate the utility of these media for reliable spectroscopic analysis.
• To create a SERS substrate that is easy to handle, store, and use.

Main Methods:

• Preparation of SERS-active media by incorporating silver (Ag) and gold (Au) nanoparticles into hydrophilic polymer gels.
• Coating the polymer-nanoparticle suspension onto substrates and drying to form stable films.
• Activating the films with aqueous analyte solutions, causing swelling and analyte-metal particle interaction.

Main Results:

• Successful preparation of large quantities of identical and stable SERS-active polymer gel films.
• Films exhibit strong SERS spectra upon analyte exposure, comparable to traditional sols.
• Dried films can be stored indefinitely, maintaining their activity and spectral reproducibility.

Conclusions:

• Hydrophilic polymer gels effectively immobilize metal nanoparticles for SERS applications.
• The developed disposable SERS films offer a cost-effective and reproducible alternative for chemical sensing.
• This method provides a convenient platform for single-use SERS analysis with excellent spectral fidelity.