Fig. 2

EIS (A) and SWV (B) recorded at different stages in 0.4 M KCl containing 0.5 mM [Fe(CN)₆]^3-/4-: bare gold electrode (a), HP₁/Au electrode (b), MCH/BSA/HP₁/Au electrode (c), TRA/MCH/BSA/HP₁/Au electrode (d), NHCR/TRA/MCH/BSA/HP₁/Au electrode (e).