Competitive immunoassay for monitoring polybrominated diphenyl ethers in PM2.5 in Shanghai

Abstract

ABSTRACTIn this paper, a sensitive biotin–streptavidin (BS)-ELISA was developed for determining the polybrominated diphenyl ethers in PM2.5. For establishing this proposed BS-ELISA, we prepared the biotinylated antibody primarily. And for reducing the background interference, some influencing factors and procedures for this immunoassay were also discussed and optimised. Under the optimal conditions, the IC50 = 0.53 ng/mL; IC10 was 0.002 ng/mL; and the results were almost consistent with those using the gas chromatography and electron capture detection (GC-ECD). Less procedures and simpler sample preparation were required for this method compared with the GC-ECD. The results showed that the highest value of BDE-47 concentration occurred in December, which might reflect the combination of heating and industrial pollution. In our analysis, we studied the Pearson correlations between BDE-47/PM2.5 and gaseous pollutants (such as NO2, SO2, CO, O3, PM10 and PM2.5). BDE-47 showed a higher correlation with NO2 than that with PM10, PM2.5 and SO2, which implied that the BDE-47 emission process might be accompanied by the emission of NO2. Moreover, during the Spring Festival, the concentration of BDE-47 in PM2.5 decreased significantly, whereas the PM2.5 changed little. This suggested factories and vehicles might be the major contributors to BDE-47 emissions (but not to PM2.5).