Biotin–streptavidin system-based real-time immuno-polymerase chain reaction for sensitive detection of 2,2′,4,4′-tetrabromodiphenyl ether in marine fish

Abstract

Polybrominated diphenyl ethers are contaminants that are widely distributed in the environment and in food samples. In this study, a highly sensitive biotin–streptavidin system-based real-time immuno-polymerase chain reaction assay (BA-IPCR) was developed to detect 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47). The BDE-47 immunogen and coating antigen were prepared, and a specific polyclonal anti-BDE-47 antibody was obtained. Several physiochemical factors in the immunoassay were optimised. The established BA-IPCR method was used to detect BDE-47 with a linearity ranging from 10 pg L−1 to 100 ng L−1. The limit of detection was 2.96 pg L−1. The recovery of the spiked samples was 92.97–107.19% and the coefficient of variation was 6.93–11.06%. The proposed method was applied to successfully detect BDE-47 in marine fish. The BA-IPCR data for the detection of BDE-47 were consistent with gas chromatography–mass spectrometry findings. The BA-IPCR method is accurate, sensitive and suitable for detecting trace amount of BDE-47 in food samples.

Keywords

• real-time immuno-polymerase chain reaction
• biotin–streptavidin system
• 2,2′,4,4′-tetrabromodiphenyl ether
• marine fish
• polyclonal antibody