Submitted to: Organohalogen Compounds
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/27/2005
Publication Date: 8/1/2005
Citation: Rubio, F., Parrotta, C.D., Li, Q.X., Shelver, W.L. 2005. Development of sensitive magnetic particle immunoassay for polybrominated diphenyl ethers. Organohalogen Compounds 67:27-30. Interpretive Summary: Polybrominated flame retardants are environmental contaminants and can accumulate through the food chain. These compounds were used in electronic equipment, plastics and textiles to prevent fires. Current analytical methods for these compounds require extensive cleanup procedures, are time consuming and need expensive instrumentation. In this report we generate a sensitive method to measure polybrominate flame retardants in different water sources (municipal, reservoir, lake, pond, and creek) that is easy to operate and rapid.
Technical Abstract: A sensitive magnetic particle based immunoassay for polybrominated diphenyl ether (PBDE) was developed. Rabbit antiserum was produced by immunizing the rabbit with 4-(2,4-dibromo-5-(2,4-dibromophenoxy)phenoxy)butyrate-BSA. The PBDE ligand and horse radish peroxidase were conjugated via NHS and EDAC reaction. The PBDEs antibody coupled magnetic particles were prepared by NHS/EDAC activation. Water samples (municipal, reservoir, lake, pond, and creek) were analyzed directly without any sample extraction or pre-concentration. The antibody can recognize BDE-47 and BDE-99 equally well, the higher the brominate substitution the less cross-reactivity was observed. The antibody has less than 0.1% cross-reactivity for Aroclor 1254. The assay is fast; fifty samples can be ran in about one hour, and sensitive, with a limit of detection of 17 ppt for BDE-47 and 20 ppt for BDE-99 (based on 90% B/B0). Water samples fortified with BDE-47 at 62.5, 125, 250 and 500 ppt were evaluated against a standard curve of 0,25, 50, 500 and 1000 ppt. The percent recovery of the fortified samples ranged from 90 – 108%, the coefficient of variation ranging from 4.0 to 5.5%. Taken together, a rapid, sensitive, accurate and precise magnetic particle based assay has been developed for ubiquitous environmental contaminant PBDEs which can serve as a cost-effective monitoring tool for water samples.