Ultrasensitive time-resolved microplate fluorescence immunoassay for bisphenol A using a system composed on gold nanoparticles and a europium(III)-labeled streptavidin tracer

作者：Du, Lingyun; Zhang, Chunyan; Wang, Longjun; Liu, Guofu; Zhang, Yuanfu; Wang, Shuhao^*

来源：Microchimica Acta, 2015, 182(3-4): 539-545.

DOI：10.1007/s00604-014-1356-9

• Time-resolved fluorescence immunoassay
• Gold nanoparticles
• Amplification technique
• Bisphenol A

We demonstrate an ultrasensitive time-resolved fluorescence immunoassay for bisphenol A (BPA) where gold nanoparticles (Au-NPs) were modified with anti-BPA antibody and thiolated dsDNA-biotin acting as a signal amplifier. In a competitive reaction, the analyte (BPA) competes with immobilized BPA-ovalbumin conjugate on the surface of microtiter plates to bind to the anti-BPA antibodies on the surface of the Au-NPs. In the next step, a Eu(III)-labeled streptavidin is added to link to the SH-dsDNA-biotin as a tracer. Fluorescence is amplified via both the Au-NPs and the biotin-streptavidin systems, and its intensity is measured in a time-resolved fluorescence immunoassay. The linear range is from 1.0 fga (TM) mL(-1) to 1.0 nga (TM) mL(-1), and the detection limit is 0.3 fg mL(-1), respectively. The method was applied to the determination of BPA in spiked water sample, with recoveries ranging from 90.2 to 106.4 %.

• 出版日期2015-2
• 单位聊城大学