Multivariate optimisation of an ultrasound assisted-matrix solid-phase dispersion method combined with LC-fluorescence detection for simultaneous extraction and determination of aflatoxins in pistachio nut samples

Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2013;30(11):1954-62. doi: 10.1080/19440049.2013.832401. Epub 2013 Sep 23.

Abstract

This paper describes the application of ultrasound-assisted matrix solid-phase dispersion as an extraction and clean-up procedure for aflatoxins (B1, B2, G1 and G2) and subsequent determination by LC-fluorescence detection. A Box-Behnken design was used to determine the parameters influencing the extraction procedure through response surface methodology and experimental design. The influence of different variables including type of dispersing phase, sample-to-dispersing phase ratio, type and quantity of clean-up phase, ultrasonication time, ultrasonication temperature, nature and volume of the elution solvent were investigated in the optimisation study. C18, graphitic carbon black and acetonitrile were selected as dispersing phase, clean-up phase and elution solvent, respectively. The optimised values were sample-to-dispersing phase ratio of 1:1, 50 mg of graphitic carbon black, 11 min ultrasonication time, 30°C ultrasonication temperature and 3 ml acetonitrile. Under the optimal conditions the limits of detection (LODs) were ranged from 0.04-0.11 µg kg(-1) and the relative standard deviations (RSDs) of the extraction method were less than 8.6%. The recoveries of the matrix solid-phase dispersion process ranged from 74% to 78% with relative standard deviation lower than 9% in all cases. Finally, the matrix solid-phase dispersion was successfully applied to extraction of trace amounts of aflatoxins in pistachio samples.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aflatoxins / analysis*
  • Analysis of Variance
  • Chromatography, High Pressure Liquid / methods*
  • Fluorometry
  • Food Analysis / methods*
  • Food Contamination / analysis
  • Magnesium Silicates
  • Nuts / chemistry*
  • Pistacia / chemistry*
  • Reproducibility of Results
  • Solid Phase Extraction / methods*
  • Ultrasonics

Substances

  • Aflatoxins
  • Magnesium Silicates
  • Florisil