Paper-Based Substrate for a Surface-Enhanced Raman Spectroscopy Biosensing Platform-A Silver/Chitosan Nanocomposite...

Area of Science:

• Materials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Paper's properties (porosity, surface area, biodegradability) make it ideal for sensor research.
• Paper-based nanocomposites are emerging substrates for surface-enhanced Raman spectroscopy (SERS).
• Existing paper-based SERS substrates face challenges like low hot spot density and poor wettability.

Purpose of the Study:

• To design and fabricate a robust silver-chitosan nanocomposite layer on paper.
• To enhance the performance of paper-based substrates for SERS applications.
• To investigate the potential for biosensing applications.

Main Methods:

• Fabrication of a silver-chitosan nanocomposite using a layer-by-layer method.
• Utilizing pH-triggered chitosan assembly for layer formation.
• Characterization of the nanocomposite structure and silver nanoparticle distribution.
• SERS measurements using 4-aminothiophenol as a model analyte.

Main Results:

• The fabricated material exhibited a nanoporous structure with evenly anchored silver nanoparticles.
• The silver-chitosan nanocomposite demonstrated improved SERS performance.
• A low detection limit of 5.13 ppb for 4-aminothiophenol was achieved.
• The mechanical properties and potential for biosensing were explored.

Conclusions:

• The developed silver-chitosan nanocomposite on paper is a promising substrate for SERS.
• The fabrication method addresses limitations of previous paper-based SERS platforms.
• The material shows potential for sensitive detection and future biosensing development.