Figure 3:Schematic illustrate a) the principle of the electrochemical impedance immunosensor for antigen detection using b) the Randle’s equivalent circuit to fit impedance spectroscopy by commercial software Autolab data analysis (EcoChemie) and c) typical Nyquist plot (Zim vs. Zre) of Faradaic impedance spectrum in presence of redox probe [Fe(CN)6]3-/4-.