An electrochemical immunosensor for the analysis of HER2 ECD in human serum samples was developed. To achieve this goal a screen-printed carbon electrode, modified with gold nanoparticles, was used as transducer surface. A sandwich immunoassay, using two monoclonal antibodies, was employed and the detection of the antibody-antigen interaction was performed through the analysis of an enzymatic reaction product by linear sweep voltammetry. The calibration curve was established between 15 and 100 ng/mL and a limit of detection of 4.4 ng/mL was achieved.
