Fast sensing of imidacloprid residue in tea using surface-enhanced Raman scattering by comparative multivariate calibration

Spectrochim Acta A Mol Biomol Spectrosc. 2019 Mar 15:211:86-93. doi: 10.1016/j.saa.2018.11.041. Epub 2018 Nov 16.

Abstract

This study focused on the fabrication of a rapid, highly sensitive and inexpensive technique for the quantification of imidacloprid residue in green tea, based on surface-enhanced Raman scattering (SERS) using highly roughned surface flower shaped silver nanostructure (as SERS substrate) coupled with the chemometrics algorithm. The basic principle of this method is imidacloprid yielded SERS signal after adsorption on Ag-NF under laser excitation by the electromagnetic enhancement and the intensity of the peak is proportional to the concentration ranging from 1.0 × 103 to 1.0 × 10-4 μg/mL. Among the models used, the GA-PLS (Genetic algorithm-partial least square) exhibited superiority to quantify imidacloprid residue in green tea. The model achieved Rp (correlation coefficient) of 0.9702 with RPD of 4.95% in the test set and RSD for precision recorded up to 4.50%. Therefore, the proposed sensor could be employed to quantify imidacloprid residue in green tea for the safeguarding of quality and human health.

Keywords: Different PLS algorithm; Flower-shaped silver nanostructure; Green tea; Imidacloprid residue; Surface-enhanced Raman scattering.

MeSH terms

  • Algorithms
  • Calibration
  • Food Contamination / analysis*
  • Food Contamination / statistics & numerical data
  • Least-Squares Analysis
  • Limit of Detection
  • Microscopy, Electron, Scanning / methods
  • Nanostructures / chemistry*
  • Neonicotinoids / analysis*
  • Nitro Compounds / analysis*
  • Silver / chemistry
  • Spectrum Analysis, Raman / instrumentation
  • Spectrum Analysis, Raman / methods*
  • Tea / chemistry*
  • X-Ray Diffraction

Substances

  • Neonicotinoids
  • Nitro Compounds
  • Tea
  • imidacloprid
  • Silver