Surface-Enhanced Raman Spectroscopy (SERS) of Neonicotinoid Insecticide Thiacloprid Assisted by Silver and Gold Nanostructures

Abstract

This study expresses our results on surface-enhanced Raman spectroscopy (SERS) analyses of neonicotinoid insecticide thiacloprid, i.e., Calypso 480 SC, in quantities much smaller than usually applied in the agricultural medicine. Advanced Ag and Au nanostructures created by the thermal deposition technique on Al2O3 ceramic were applied as active substrates for SERS analyses. The minimum concentration of thiacloprid detected was 380 µM and the enhancement factor was estimated to be about 3 × 103. The intensity of the SERS peaks increased by an order of magnitude after pulsed laser annealing of the films and formation of nanoparticle arrays and the enhancement factor reached ≈104, respectively. The proposed study has direct bearing on the environment and human health by detection of small amounts or residue of harmful pollutants using a relatively cheap and easy method to produce active SERS substrates.