Premium
Immunonanogold Catalytic Resonance Scattering Spectral Assay of Trace Immunoglobulin M
Author(s) -
LIANG AiHui,
WANG SuMei,
JIANG ZhiLiang
Publication year - 2008
Publication title -
chinese journal of chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.28
H-Index - 41
eISSN - 1614-7065
pISSN - 1001-604X
DOI - 10.1002/cjoc.200890258
Subject(s) - chemistry , trisodium citrate , detection limit , resonance (particle physics) , colloidal gold , buffer solution , polyethylene glycol , scattering , centrifugation , light scattering , analytical chemistry (journal) , chromatography , nuclear chemistry , nanoparticle , biochemistry , nanotechnology , physics , materials science , particle physics , optics
Gold nanoparticles of 10 nm were prepared by the improved method of trisodium citrate, and used to label goat anti‐human immunoglobulin M (anti‐IgM) to obtain a resonance scattering spectral probe for IgM. In pH 4.5 KH 2 PO 4 ‐Na 2 HPO 4 buffer solution and in the presence of polyethylene glycol, the nanogold‐labeled anti‐IgM was combined with IgM specifically to form immunogold complex particles. After centrifugation, the immunonanogold in the supernatant catalyzed the reduction of AuCl 4 − ions by NH 2 OH·HCl to form larger size gold particles in pH 1.9 citrate buffer solution, making the resonance scattering intensity at 580 nm enhanced. The amount of the nanogold‐labeled anti‐IgM in the supernatant decreased with the addition of IgM. The decreased intensity Δ I 580 nm was proportional to the concentration of IgM in the range of 0.06–4.80 ng·mL −1 . The regression equation was Δ I 580 nm =14.5 c (IgM)+1.8, with a detection limit of 0.03 ng·mL −1 IgM. The method was applied to the determination of IgM in sera of healthy humans, with satisfactory results.