摘要
An ultrasensitive ectrochemiluminescense (ECL) immunoassay was proposed by using magnetic microbeads as the carrier of ECL labels for ECL signal amplification. First, polyclonal antibody (pcAb) of abrin was immobilized on a microplate. Then, abrin was bound to pcAb. Next, biotinylated monoclonal antibody (mcAb) was conjugated to abrin, yielding the sandwich immunocomplex on the plate. After that, Ru(bpy)(3)(2+) labeled magnetic microbeads were conjugated on the plate through specific biotin-streptavidin interaction. Finally, Ru(bpy)(3)(2+) labeled magnetic microbeads were released from the plate, and ECL of Ru(bpy)(3)(2+) was measured for abrin determination. A logarithmic linear relationship between ECL intensity and abrin concentration in the range of 2-200 ng L-1 was obtained. The linear regression equation was lgY = 1.295lgX + 0.201 (R = 0.995, n = 7, p < 0.0001), and the detection limit was 2 ng L-1. This new approach holds great promise for highly sensitive detection of target proteins in various fields such as biodiagnostics, environmental monitoring and biodefense.
- 出版日期2013-12