ELECTROCHEMICAL SCIENCE Carcinoembryonic Antigen Immunosensor Developed with Organoclay Nanogold Composite Film

Justin Claude Kemmegne-Mbouguen, Emmanuel Ngameni, Priscilla Baker, Tesfaye Waryo, Boitumelo Kgarebe, Emmanuel Iwuoha, Africa South
2014 Int. J. Electrochem. Sci   unpublished
Organoclay nanogold composite were prepared using gold nanoparticles and the natural Cameroonian clay grafted with amino organosilane. The functionnalization of clay provided abundant amino group to assemble gold nanoparticles. A label-free electrochemical immunosensor for the sensitive determination of carcinoembryonic antigen (CEA) was fabricated by immobilizing anti-CEA onto organoclay nanogold composite film modified electrode by the cross-linking method using glutaraldehyde. In addition,
more » ... yde. In addition, the preparation procedure of the immunosensor was investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under optimal conditions, the resulting immunosensor displayed a high sensitivity for the detection of CEA, and responded to the CEA concentration in two ranges from 0.05 to 5.0 ng/mL (R = 0.991) and from 5.0 to 120.0 ng/mL (R = 0.998) with a detection limit of 0.01 ng/mL.