Paper electrophoretic enrichment-assisted ultrasensitive SERS detection

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Nanotechnology

Background:

• Surface-enhanced Raman spectroscopy (SERS) requires effective molecular enrichment in "hot spots" for sensitive trace substance detection.
• Traditional methods often face limitations in sensitivity and convenience for fluid sample analysis.

Purpose of the Study:

• To develop a convenient and highly sensitive method for trace substance detection in fluids using paper electrophoresis integrated with SERS.
• To enhance analyte concentration at silver nanoparticle (AgNP) surfaces for improved Raman signal amplification.

Main Methods:

• Utilized a glass fibre paper substrate functionalized with silver nanoparticles (AgNPs).
• Employed paper electrophoresis integrated with field amplification sample stacking (FASS) and capillary effects for analyte enrichment.
• Investigated the combined effects of electrophoretic enrichment and surface plasmon enhancement from AgNPs.

Main Results:

• Achieved significant improvement in detection limits for Raman and SERS by over an order of magnitude.
• Demonstrated a SERS detection limit as low as 10^-17 M for Nile Blue A.
• Successfully detected trace organic contaminants at the parts-per-trillion (ppt) level in real-world applications.

Conclusions:

• The developed paper electrophoretic enrichment method offers a flexible and highly sensitive platform for SERS analysis.
• This approach provides a convenient and effective means for detecting trace contaminants in aquaculture and food safety.
• The integration of electrophoresis with SERS on a paper substrate opens new avenues for portable and sensitive analytical tools.