Donor/acceptor nanoparticle pair-based singlet oxygen channeling homogenous chemiluminescence immunoassay for quantitative determination of bisphenol A

Bisphenol A (BPA) is widely used in consumer products such as plastic bottles and food containers. It has become a ubiquitous environmental contaminant and poses a serious risk to human health. A rapid, sensitive, and high-throughput method for detecting BPA is therefore desirable. Herein, a donor/acceptor nanoparticle pair-based singlet oxygen channeling chemiluminescence homogenous immunoassay is developed for the determination of BPA. The donor nanoparticles were modified with phthalocyanine as a photosensitizer and were then coated with streptavidin. The acceptor nanoparticles were doped with thioxene derivatives and Eu(III) as a chemiluminescence emitter and then coated with anti-BPA antibody. Under light irradiation, oxygen near the donor surface transforms to singlet oxygen (O-1(2)), which migrates to the acceptor and reacts with it, generating luminescence. Because O-1(2) has a very short lifetime, luminescence is generated only when the donor and acceptor are in close proximity. This occurs when they are brought together by the antigen/antibody and streptavidin/biotin reaction. Based on this singlet oxygen channeling mechanism, a competitive homogenous chemiluminescence immunoassay for BPA was developed on 384 microplates. The assay exhibited linear detection over the range 10-1000 ng/mL and a limit of detection of 2.9 ng/mL. The intra- and inter-assay precisions were both below 5.1 %. The average recoveries of three spiked samples in tap and river water samples were in the range 95.5-121.0 %, in agreement with values obtained using high-performance liquid chromatography. The homogeneous assay is rapid, low cost, sensitive, and allows high-throughput, so is well suited for screening large numbers of environmental samples