▎ 摘　　要

In the present work, sensitive and stable sandwiched electrochemical immunosensing strategies with graphene (Gr)/gold nanoparticles (GNP) composite as the immobilization platform and ferrocene (Fc) derivatives as labels were proposed. Under the optimal choice and the proposed immunosensing strategy, with 1,1'-ferrocenedicarboxylic acid label, the human IgG could be detected specifically with a low detection limit of 0.4 ng/mL and a wide linear dynamic range from 1 to 300 ng/mL. Meanwhile, the electrochemical behavior of three different ferrocene derivatives labels was studied. (C) 2012 Elsevier B.V. All rights reserved.