Rapid Assay of Trace Immunoglobulin M by a New Immunonanogold Resonance Scattering Spectral Probe

Abstract

Nanogold, 8 nm in size, was used to label goat antihuman 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 IgM to form nanogold-labeled immunocomplex causes the RS intensity at 580 nm to be enhanced, in pH 4.49 KH 2 PO 4 -Na 2 HPO 4 buffer and in the presence of polyethylene glycol 6000. The enhanced RS intensity at 580 nm (ΔI 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. (Journal of Biomolecular Screening 2008:302-308)

Electrochemical Biosensor with Enhanced Antifouling Capability Based on Amyloid-like Bovine Serum Albumin and a Conducting Polymer for Ultrasensitive Detection of Proteins in Human Serum

“…The limit of detection (LOD) of the biosensor was calculated to be 2.32 pg mL –1 , which was much lower than the LODs of the previously reported IgM biosensor (Table S1). − The low LOD may be due to the superiority of the AL-BSA-modified electrode with outstanding stability and excellent antifouling capability, which provides a low noise signal for high specificity of IgM.…”