Abstract

A disposable electrochemical immunosensor for carcinoembryonic antigen (CEA) was proposed based on the antigen immobilized in a colloidal gold nanoparticles modified chitosan membrane on the surface of an indium-tin oxide (ITO) electrode. The different membranes were characterized by scanning electron microscope and electrochemical methods. Based on a competitive immunoassay format, the immobilized antigen of the immunosensor was incubated with a horseradish peroxidase (HRP) labeled antibody and sample CEA antigen, and the formed immunoconjugate in the immunosensor was detected by an o-phenylenediamine-H(2)O(2)-HRP electrochemical system. Under the optimal experimental conditions, the electrocatalytic current decreased linearly with the competitive mechanism. CEA could be determined in the linear range from 2.0 to 20 ng/ml with a detection limit of 1.0 ng/ml. The prepared CEA immunosensor is not only economic due to the low-cost ITO electrode obtained from industrial mass production, but is also capable with good stability and reproducibility for batch fabrication.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call