Fluorescence polarization assay for the simultaneous determination of bisphenol A, bisphenol F and their diglycidyl ethers in canned tuna

This work developed a fluorescence polarization (FP) assay for simultaneous monitoring BPA, BPF, BADGE, and BFDGE in canned tuna. The assay was based on the competitive binding between bisphenol analogues (BPs) and dexamethasone fluorescein (Dex-fl) for mouse peroxisome proliferator-activated receptor α ligand binding domain (mPPARα-LBD*). The soluble form of mPPARα-LBD* was expressed in Escherichia coli strain Rosetta (DE3), as a recognition element on detection of BPs. Under optimized conditions, four bisphenol analytes were detected at concentrations corresponding to the specific migration limits (SMLs) as required by the European Union. The FP assay showed IC50 values of 2.80, 6.51, 1.72, and 4.28 mg L−1 with a limit of detection of 0.35, 0.08, 0.10, and 0.49 mg L−1 for BPA, BPF, BADGE, and BFDGE, respectively. The analysis of spiked canned tuna samples showed the acceptable recoveries ranged from 87.9% to 77.3%, with variation coefficients ranging from 9.0% to 15.8%. With the high sensitivity and wide-range affinities to BPs, the developed assay based on mPPARα-LBD* exhibited the potential to be a screening assay for fast detection of BPs in canned tuna.