▎ 摘　　要

A three-dimensional porous network graphene aerogel (GAs) with large specific area and excellent conductivity was loaded with ss-cyclodextrin polymer (P ss-CD) to serve as a support for immobilization of antibodies. A highly sensitive immunosensor for the cancer marker carbohydrate antigen 15-3 (CA15-3) was designed based on the use of P ss-CD/ GAs. The large specific area of GAs warrants high loading with antibodies, and their excellent electrical conductivity warrants strong electrical signals. Based on the synergistic effect of GAs and P ss-CD, an immunoassay was designed that is making use of hexacyanoferrate as an electrochemical probe and having a pleasantly low working potential of 0.2 V (vs. SCE). Response is linear in the 0.1 mU mL-1 to 100 U mL-1 activity range, and the lower detection limit is 0.03 mU mL-1 (at S/ N = 3). The immunoassay is stable, selective and reproducible. It was applied to the analysis of spiked samples, and results were satisfactory.