A new atomic absorption spectral assay for the determination of trace IgG using immunonanogold.
Nanogold in size of 10 nm was used to label goat anti-human IgG (GIgG) to obtain an immunonanogold probe (AuGIgG) for IgG. In pH 6.8 phosphate buffer solution and in the presence of immunoprecipitator polyethylene glycol 6000 (PEG 6000), IgG reacted with the probe (AuGIgG) to form AuGIgG-IgG-PEG immunocomplex. After the centrifugation to remove the immunocomplex, AuGIgG in the supernatant can be measured by atomic absorption spectrophotometry at gold absorption line 242.8 nm. The results showed that the absorption value decreased as the concentration of IgG increased, and the decreased absorption value was linear to IgG concentration in the range 0.025-0.375 μg/mL, with a detection limit of 0.008 μg/mL. On this base, a new nanogold-labeled atomic absorption spectral assay for IgG was established. The assay was applied to determine IgG in human serum sample with satisfactory results.
Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Ministry of Education, School of Environment and Resource, Guangxi Normal University, Guilin, China.
Yafang
Y
Tang
Caina
C
Jiang
Aihui
A
Liang
Jishun
J
Li
Zhiliang
Z
Jiang
D004305:Dose-Response Relationship, Drug; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007074:Immunoglobulin G / Q000737:chemistry*; D007150:Immunohistochemistry / Q000379:methods*; D007834:Lasers; D036103:Nanotechnology / Q000379:methods*; D011092:Polyethylene Glycols / Q000737:chemistry; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D013054:Spectrophotometry, Atomic / Q000379:methods*
D007074:Immunoglobulin G; D011092:Polyethylene Glycols