Rapid assay of trace immunoglobulin M by a new immunonanogold resonance scattering spectral probe

摘要

Nanogold, 8 nm in size, was used to label goat anthuman immunoglobulin M (GIgM) to obtain a new immunonanogold resonance scattering (RS) probe (Au-GIgG) for quantitation of trace immunoglobulin M (IgM). The Au-GIgG combined with I-M to form nanogold-labeled immunocomplex causes the RS intensity at 580 nm to be enhanced, in PH 4.49 KH2PO4-Na2HPO4 buffer and in the presence of polyethylene glycol 6000. The enhanced RS intensity at 580 nm (Delta I-580 (nm)) is Proportional to the IgM concentration in the range of 1.5 to 2000 ng/mL, with a lower detection limit of 0.98 ng/mL. The immunonanogold RS assay was used to assay IgM in serum samples, with sensitivity, selectivity, and simplicity.