Fabrication of Encapsulated and Sticky Surface-Enhanced Raman Spectroscopy Substrate Coupling with Thin Layer Chromatography for Determination of Pesticide

Abstract

A sealed and sticky surface-enhanced Raman scattering (SERS) substrate was fabricated by screen-printed technology. The screen-printed ink was prepared by mixing poly(ethylene glycol) diacrylate (PEGDA), Ag nanoparticles (Ag-NPs) and photoinitiator. After printed on supporting material, PEGDA can polymerize into film under UV light illumination. Ag-NPs were sealed and protected by this film. SERS signal of 10-12 M rhodamine 6G has been recorded on this substrate. The homogeneity of this substrate was examined by mapping experiments, and the relative standard deviation of the signals from 48 points was within 10%, indicating high uniformity of this substrate. Upon coupling with thin layer chromatography (TLC), this sticky SERS substrate can be in thorough contact with the separated targets on TLC plates and stick to them firmly by pressing a cover, which was effective for improving the detection sensitivity. This coupling technology exhibited good performance for determination of thiabendazole in complex matrix with a detection limit of 0.01 μg/mL.

Keywords: Surface-Enhanced Raman Scattering, thin layer chromatography, Pesticide residue, Screen-printed