Flow injection chemiluminescence immunosensor for the determination of clenbuterol by immobilizing coating-antigen on carboxylic resin beads

In this paper, a flow-injection chemiluminescence (CL) immunoassay based on a transparent immunoaffinity reactor is reported for the detection of clenbuterol (CLB). The reactor prepared with coating-antigen immobilized on carboxylic resin beads was used as an immunosensor and was incorporated in a CL reaction system based on p-iodophenol-luminol-H2O2 in the presence of horse radish peroxidase (HRP) as an enzyme tracer. With a competitive immunoassay format, the decrease in CL intensity was proportional to the increase of clenbuterol concentration in the range of 0.40-120 ng mL(-1) with a correlation coefficient of 0.999 (n = 9) and a limit of detection of 0.20 ng mL(-1) at S/N of 3. The stability, specificity and reproducibility of the fabrication of the immunosensor system were good. The system was applied in the analysis of real samples with satisfactory results and has good potential for use in the screening of trace amounts of CLB residue.