CE-based noncompetitive immunoassay for immunoglobulin G in bovine colostrum products.
A CE-based noncompetitive immunoassay for IgG in bovine colostrum products was established. FITC-labeled protein G (FITC-PrG) was tagged through noncovalent bindings to the Fc region of the mouse monoclonal antibovine IgG (Ab). The FITC-PrG, Ab, and IgG formed a sandwiched immunocomplex FITC-PrG-Ab-IgG under optimal incubation conditions. The immunocomplex was separated and analyzed by CZE with LIF detection in less than 2 min in an uncoated fused-silica capillary. Addition of PEG 20,000 (PEG 20M) in the running buffer significantly suppressed analyte adsorption and thus improved the reproducibility and the resolution. The precision of the method was 5.1% (n = 7). A linear relationship was established for the IgG concentration in the range of 1-5 mg/L with a linear correlation coefficient (r = 0.9917). The LOD was 0.1 mg/L (S/N = 3). The method was successfully applied for the determination of IgG in bovine colostrum products and satisfactory results were achieved.
Zhao
Jin
J
Beijing Center for Disease Prevention and Control, Beijing, P. R. China.
Ding
Xiaojing
X
Wang
Xinyu
X
Wang
Qian
Q
Wang
Zhi
Z
D000818:Animals; D000915:Antibody Affinity; D001426:Bacterial Proteins / Q000737:chemistry; D001666:Binding Sites, Antibody; D015374:Biosensing Techniques; D002417:Cattle; D003126:Colostrum / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry; D007118:Immunoassay / Q000379:methods*; D007074:Immunoglobulin G / Q000032:analysis*; D007834:Lasers; D051379:Mice; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
D001426:Bacterial Proteins; C034284:IgG Fc-binding protein, Streptococcus; D007074:Immunoglobulin G; D016650:Fluorescein-5-isothiocyanate