Simultaneous Determination of Aflatoxins and Benzo(a)pyrene in Vegetable Oils Using Humic Acid-Bonded Silica SPE HPLC-PHRED-FLD.

In the present work, a rapid, accurate, and cost-effective method was developed for the simultaneous quantification of aflatoxins and benzo(a)pyrene in lipid matrices, using solid-phase extraction (SPE) via humic acid-bonded silica (HAS) sorbents, followed by high-performance liquid chromatography coupled with photochemical post-column reactor fluorescence spectroscopy (HPLC-PHRED-FLD) analysis. The major parameters of extraction efficiency and HPLC-PHRED-FLD analysis were investigated and this method was fully validated. The limits of quantification and the limits of detection were 0.05-0.30 and 0.01-0.09 µg kg -1 , respectively. The recoveries were 66.9%-118.4% with intra-day and inter-day precision less than 7.2%. The results of 80 oil samples from supermarkets indicated a high occurrence of BaP, and most of concentrations were within the requirements of EU and China food safety regulations. This is the first utilization of HAS-SPE HPLC-PHRED-FLD to simultaneously analyze the occurrence of aflatoxins and benzo(a)pyrene in vegetable oils.