A chemiluminescent immunosensor based on antibody immobilized carboxylic resin beads coupled with micro-bubble accelerated immunoreaction for fast flow-injection immunoassay.
A novel immunoaffinity column used as an immunosensor for flow-injection chemiluminescent (CL) immunoassay was prepared by immobilizing antibody on carboxylic resin beads. The immunosensor could fast recognize and trap the immunocomplex of horseradish peroxidase (HRP)-labeled antibody and antigen, which was firstly formed with a micro-bubble accelerated pre-incubation process, to produce a sandwich immunocomplex. The HRP introduced in the immunoaffinity column could catalyze the CL reaction to produce enzyme-enhanced emission. With alpha-fetoprotein (AFP) as a mode, a flow-injection CL immunoassay was proposed. The whole assay for one sample, including the pre-incubation and the regeneration of immunoaffinity column, could be performed within 16 min. The linear range was 1.0-80 ng/ml with a correlation coefficient of 0.998 and a detection limit of 0.1 ng/ml at a signal/noise ratio of 3. The intra- and inter-assay coefficients of variation at 20 ng/ml AFP were 1.2% and 8.5%, respectively. The storage stability of the immunoaffinity column and the accuracy for sample detection were acceptable. This flexible, sensitive, low-cost, and rapid method is valuable for clinical immunoassay.
Yang
Zhanjun
Z
Key Laboratory of Analytical Chemistry for Life Science (Ministry of Education of China), Department of Chemistry, Nanjing University, Nanjing, PR China.
Fu
Zhifeng
Z
Yan
Feng
F
Liu
Hong
H
Ju
Huangxian
H
D015374:Biosensing Techniques / Q000379:methods*; D002846:Chromatography, Affinity; D017022:Flow Injection Analysis / Q000379:methods*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007475:Ion Exchange Resins; D008163:Luminescent Measurements; D015203:Reproducibility of Results; D000509:alpha-Fetoproteins / Q000032:analysis*
D007475:Ion Exchange Resins; D000509:alpha-Fetoproteins