This paper describes a sensitive and simple method for the determination of bisphenol A (BPA) and bisphenol AF (BPAF) in vinegar samples using two-component mixed ionic liquid dispersive liquid-phase microextraction coupled with high performance liquid chromatography. In this work, BPA and BPAF were selected as the model analytes, and two-component mixed ionic liquid included 1-butyl-3-methylimidazolium hexafluorophosphate ([C4Mim]PF6) and 1-hexyl-3-methyl-imidazolium hexafluorophosphate ([C6Mim]PF6) was used as the extraction solvent for the first time here. Parameters that affect the extraction efficiency were investigated. Under the optimum conditions, good linear relationships were discovered in the range of 1.0-100 μg/L for BPA and 2.0-150 μg/L for BPAF, respectively. Detection limits of proposed method based on the signal-to-noise ratio (S/N=3) were in the range of 0.15-0.38 μg/L. The efficiencies of proposed method have also been demonstrated with spiked real vinegar samples. The result show this method/ procedure to be a more efficient approach for the determination of BPA and BPAF in real vinegar, presenting average recovery rate of 89.3-112 % and precision values of 0.9-13.5% (RSDs, n = 6). In comparison with traditional solid phase extraction procedures this method results in lower solvent consumption, low pollution levels, and faster sample preparation.

Zhigang Tai, Yingtang Li, Mousheng Liu, Xujia Hu, Yaling Yang and Benkui Qin