Development of multifunctional 3D nanostructure substrate with solid phase extraction and surface-enhanced Raman...

Area of Science:

• Analytical Chemistry
• Materials Science
• Spectroscopy

Background:

• Surface-enhanced Raman scattering (SERS) is a sensitive technique limited by matrix interference and low analyte concentrations in complex samples.
• Existing SERS methods often require complex sample preparation, hindering rapid on-site analysis for food and environmental safety.

Purpose of the Study:

• To develop a multifunctional, low-cost Glass Fiber SERS (GF-SERS) platform for integrated solid-phase extraction (SPE) and SERS detection.
• To enhance SERS sensitivity, reproducibility, and simplify workflows for food and environmental safety assessments.

Main Methods:

• Fabrication of GF-SERS substrate using two-stage sputtering, thermal annealing, and oxygen plasma treatment to create silver nanoparticle (AgNP) hotspots.
• Integration of SPE functionality within the porous glass fiber matrix for sample enrichment and matrix effect mitigation.
• SERS detection of malachite green (MG) to evaluate platform performance, including limit of detection (LOD) and analytical enhancement factor (AEF).

Main Results:

• Achieved a high-density distribution of AgNP hotspots with controlled nanogaps, resulting in exceptional signal reproducibility (RSD = 9%).
• Demonstrated a simplified "capture-to-detection" workflow by integrating SPE directly into the GF-SERS substrate.
• Obtained a wide linear detection range for malachite green (MG) with a low LOD of 0.76 ppb and a high AEF of 1.28 x 10^5.

Conclusions:

• The integrated SPE-GF-SERS platform offers a robust and cost-effective solution for rapid on-site food and environmental safety assessments.
• The platform effectively overcomes matrix effects and low analyte concentration challenges, enabling reliable detection of contaminants.
• This approach provides a versatile tool for identifying illegal additives in complex samples like milk and pond water.