Chemiluminescence imaging immunoassay for simultaneous determination of TBBPA-DHEE and TBBPA-MHEE in aquatic environments.

The environmental concentration of tetrabromobisphenol A bis(2-hydroxyethyl) ether (TBBPA-DHEE) and tetrabromobisphenol A mono(hydroxyethyl) ether (TBBPA-MHEE), as some of the main derivatives and byproducts of tetrabromobisphenol A (TBBPA), are obscure due to lacking available analytical methods. In the present study, a multiplexed competitive chemiluminescent imaging immunoassay (CLIIA) based on specific monoclonal antibody respectively against TBBPA-MHEE and TBBPA-DHEE has been developed for the simultaneous detection of the two targets. To improve the sensitivity of immunoassay, Au nanoparticles (AuNPs) were utilized as solid support for loading horseradish peroxidase, labeled to obtain the multi-enzyme particles. Under the optimized conditions, the limits of detection (LODs) for TBBPA-MHEE and TBBPA-DHEE were 1.85 ng/mL and 2.05 ng/mL, respectively. After estimating its accuracy and precision, the established method was applied for investigation of the contaminants at the inner rivers in Zhenjiang, Jiangsu Province. Our results indicated that no TBBPA-MHEE was found in all 11 water samples and two samples of TBBPA-DHEE were detected up to 6.34 ng/mL, possibly ascribed to the dense population and slow flow rate around the sampling site. Graphical abstract.