Application of Microgel as a Sorbent for Bisphenol Analysis in Liquid Food Samples

Featured Application The synthesized microgels can become a cost-effective sorbent for the removal of bisphenols from an aqueous medium. Bisphenols are well-known endocrine disruptors that can easily migrate from plastic and can containers to food. Due to the complicated matrix and ultra-low concentrations of bisphenols in food, samples require extensive preparation before instrumental analysis. In this paper, an environmental sensitive microgel was employed as a sorbent for the preconcentration of four bisphenols, bisphenol A (BPA), bisphenol B (BPB), bisphenol E (BPE) and bisphenol F (BPF), from liquid food samples. Liquid chromatography with fluorescence detection (LC-FLD) was used for the quantification of bisphenols. By applying microgel solid-phase extraction procedure, the limits of detections achieved in liquid food samples can be lowered to 0.9 mu g center dot L-1 for BPF and BPA, 2.3 mu g center dot L-1 for BPE and 2.9 mu g center dot L-1 for BPB. Only 5 mg of microgel was sufficient to achieve good recoveries (70.5-109%) with precision (RSD 0.21-5.01%, n = 3) for different analyzed liquid food samples spiked at concentration levels of 50 mu g center dot L-1. In five out of twelve of the analyzed samples (pineapple, mandarin, peach, mushroom and pickles), they were contaminated with BPA, and the determined concentration was in the range of 6.2-22 mu g center dot L-1; however, these results are below the specific migration limit (SML) set for BPA (50 mu g center dot kg(-1)).