MoS2 quantum dots for on-line fluorescence determination of the food additive allura red

Food Chem. 2021 May 30:345:128628. doi: 10.1016/j.foodchem.2020.128628. Epub 2020 Nov 13.

Abstract

This work presents an on-line fluorescence method for the allura red (AR) determination. The method is based on the fluorescence quenching of dots of MoS2 because of their interaction with the non-fluorescence dye. MoS2-dots were synthetized and characterized by spectroscopic techniques and High Resolution Transmission Electronic Microscopy (HR-TEM). The simultaneous injection of the nanomaterial and the dye in a flow injection analysis system allows the determination of allura red at 1.7 × 10-6 M concentration level with a very good accuracy and precision (Er minor than 10% and RSD lower than 8%) and a sampling frequency of 180 samples per hour. Moreover, the interaction fluorophore-quencher results a dynamic inhibition mechanism. The proposed methodology was applied to the AR analysis in soft beverages and powders for gelatine preparation. Colourant concentrations of 63 ± 2 mg/L (n = 3) and 0.30 ± 0.01 mg/g (n = 3) were found, respectively. These results were validated by high performance liquid chromatography technique.

Keywords: Allura red; Dots; Flow injection analysis; Fluorescence inhibition; Food additive; Molybdenum disulfide.

MeSH terms

  • Azo Compounds / analysis*
  • Beverages / analysis
  • Disulfides / chemistry*
  • Fluorescent Dyes / chemistry
  • Food Additives / analysis*
  • Molybdenum / chemistry*
  • Quantum Dots / chemistry*
  • Spectrometry, Fluorescence / methods*

Substances

  • Azo Compounds
  • Disulfides
  • Fluorescent Dyes
  • Food Additives
  • Allura Red AC Dye
  • Molybdenum
  • molybdenum disulfide