Electrochemical immunosensor with graphene/gold nanoparticles platform and ferrocene derivatives label

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.

► A sensitive electrochemical immunosensor was fabricated with new platform and label.
► Gold nanoparticles/graphene platform was fabricated with an easy electrodeposition method.
► 1,1′-ferrocenedicarboxylic acid was first introduced as the label.
► Three different ferrocene derivatives labels were compared and discussed.