Poly(MAA-PEGMA)-coated superparamagnetic nanoparticles-based magnetic affinity immunoassay for detection of interleukin-6

Using poly(maa-pegma)-coated superparamagnetic nanoparticles (pmnps) as carrier, a rapid and sensitive immunoassay for quantitative determination of interleukin-6 (il-6) has been developed for the first time. this protocol involved a sandwich format in which the il-6 in samples was first captured by the primary monoclonal antibody (mab) immobilized on the surface of pmnps, and then recognized by the second monoclonal antibody labeled with horseradish peroxidase (hrp-mab). the hrp-mab dilution and immunoreaction time were examined and optimized. the linear range for il-6 assay was 3.2-1000 pg ml^-1, and the limit of detection (lod) was 1.0 pg ml^-1. the developed immunoassay method showed high precision, high sensitivity, acceptable recovery and relatively good reliability, and could be used to detect serum il-6 levels with consistent results in comparison with those obtained by the enzyme-linked immunosorbent assay (elisa) method.