Fig. 4. (A) SWV of different fabricated immunosensors for the detection of 500 ng mL−1 AFP constructed from (a) GCE/antibody@BSA, (b) GCE/MnO2NRs@antibody/BSA, (c) GCE/AuNPs@antibody/BSA and (d) GCE/MnO2NRs @AuNPs@antibody/BSA (B) SWV of different concentrations of AFP from 0.005 to 500 ng mL−1 in 1 mM [Fe(CN)6]3−/4− in 0.1 M KCl at 25 Hz (C) EIS of different concentrations of AFP from 0.005 to 500 ng mL−1 using 1 mM [Fe(CN)6]3−/4− in 0.1 M KCl and the equivalent circuit employed to fit the experimental impedance data (inset).
