▎ 摘　　要

Herein, a new label-free electrochemical immunosensor was constructed for carcinoembryonic antigen (CEA) detection based on AgPt nanorings supported on reduced graphene oxide (AgPt NRs-rGO) synthesized by a one-pot wet-chemical route with the assistance of 2,4-dihydroxypyridine (DHP) as a new growth-directing agent. The nanocomposites were mainly characterized by transmission electron microscopy (TEM), high-resolution TEM (HRTEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). By virtue of the incorporated Ag as the redox mediator, the AgPt NRs-rGO-based immunosensor showed the wide linear range of 5 fg mL(-1)-50 ng mL(-1) for the detection of CEA, with a low detection limit of 1.43 fg mL(-1), which providing a promising platform for clinical research and diagnosis. (C) 2017 Elsevier B.V. All rights reserved.