Highly sensitive carcinoembryonic antigen detection using Ag@Au core–shell nanoparticles and dynamic light scattering

High level of carcinoembryonic antigen (CEA) can signal the presence of cancer directly. Thus simple and sensitive detection of CEA is of great importance. Here, sensitive CEA detection in human serum was realized by using Ag@Au core–shell nanoparticles (CSNPs) and dynamic light scattering (DLS) based on monitoring the average diameter change of Ag@Au CSNPs after the specific bind between CEA antibody (anti-CEA) and CEA. Under optimal conditions, CEA could be detected linearly in the range of 60 pg/mL to 50 ng/mL, with a detection limit of 35.6 pg/mL. Moreover, satisfactory results were obtained when the assay was used in human serum CEA detection.