A highly sensitive and rapid biological probe enhanced real-time immuno-polymerase chain reaction for detecting 2,2′,4,4′-tetrabromodiphenyl ether in indoor airborne particles

Polybrominated diphenyl ethers (PBDEs) are bromine flame retardants that are widely distributed in the environment. In this study, 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) was used as a model PBDE compound. Based on the preparation of BDE-47 immunogen, coating antigen and polyclonal anti-BDE-47 antibody, a highly sensitive and rapid real-time immuno-polymerase chain reaction using biological probes (BP-IPCR) was developed to detect BDE-47 in indoor airborne particles. Several physiochemical factors that might influence the assay performance were optimised, such as OVA-BDE-47 and the biological probe concentration, primer concentration and annealing temperature. Under the optimal conditions, a standard curve was constructed with BDE-47 concentrations ranging from 5 pg L^?1 to 50 ng L^?1. The limit of detection was 1.32 pg L^?1. The BP-IPCR assay was highly selective, presenting low cross-reactivity values with BDE-47 analogues (below 5.26%). The recoveries of spiked samples were 92.6–107.9% and the coefficients of variation were 3.7–8.8%. The BP-IPCR data for the detection of BDE-47 in indoor airborne particles was consistent with gas chromatography-mass spectrometry findings (R² = 0.9849). This immunoassay is sensitive and reliable; it can be used for specific and sensitive batch detection of BDE-47 in environmental samples.