Development Of A Fluorescence Polarization Assay For The Simultaneous Determination Of Bisphenol A,Bisphenol F And Their Diglycidyl Ethers In Canned Tuna

Endocrine disrupting substances(EDCs)are exogenous chemical substances that interfere with the endocrine system and,after entering the body,alter endocrine functions by mimicking or inhibiting endogenous hormone functions.The contamination of the EDCs in the inner coating is a very serious food safety problem.Bisphenol A(BPA)and bisphenol F(BPF)in industrial applications,mainly used as monomers,such as epoxy resin and polycarbonate production;used as plasticizer in antioxidants;used as soft polyvinyl chloride(PVC)polymerization inhibitor in production of vinyl chloride.BADGE and BFDGE are polymerized by BPF,BPA and epichlorohydrin respectively.They are used as a starting agent for food cans,protective coatings and additives in PVC organic solvent resins to remove hydrochloric acid from the reaction process.Moderate high lipophilicity and incomplete polymerization are likely to cause residual bisphenol compounds(BPs),and residual BPs may migrate to the environment,food or food containers,consumer products,and the human body.These compounds are widely used as internal coating materials for canned food,so the determination of BPs in food has attracted much attention.This study based on peroxisome proliferator activated receptor(PPARs)can specifically identify bisphenol A,canned tuna BPs residue fluorescence polarization detection method.Compared with antibodies,the advantage of receptors is that they can identify a number of targets and are easy to mass prepare and have stable properties.Receptor detection and analysis technology is to detect residual BPs in the tested samples,this detection technology is very important for the detection of BPs residues.The main research conclusions are as follows:The mPPAR?-LBD* was expressed in Escherichia coli strain Rosetta(DE3)and the target protein was obtained.SDS-PAGE and Western blot analysis showed that the protein was basically removed,and the soluble recombinant protein mPPAR?-LBD* with His tag was obtained.The concentration of recombinant protein after enrichment was 0.72mg/mL.The binding ability of recombinant protein binding ligand was verified by the saturation binding test of mPPAR-LBD* probe.mPPAR?-LBD* was used as an identification element,and dexamethasone fluorescein(Dex-fl)was used as a fluorescent probe for fluorescence polarization detection.The optimized reaction conditions were as follows: probe concentration 8nM,protein concentration 8nM,incubation time was 40 min.Under the optimized conditions,the concentration of 4 bisphenol compounds can be determined according to the specific transport volume(SML)formulated by the European union.FP analysis showed that the median inhibitory concentration(IC50)of BPA,BPF,BADGE and BFDGE was 12.27?19.13?8.58 and 13.69?M,respectively,and the detection limits were 1.52?0.24?0.50 and 1.55?M,respectively.Analysis of canned tuna samples showed that the acceptable rate of recovery was 78.1%-87.9%,with a coefficient of variation of 9.0%-15.8%.In summary,fluorescence polarization immunoassay has the potential to rapidly detect BPs in canned tuna.