Fig. 5. (A) Voltammetric response as a function of H₂O₂ concentration of SO-Cyt generated in situ upon pretreatment with H₂O₂ of Cyt-c adsorbed on an NH₂-SAM electrode. All measurements were performed in 10 mM phosphate buffer, pH = 7, at 0.05 V s^–1. The arrow indicates increasing concentrations of H₂O₂ from 0 to 2 mM. (B) Normalized cathodic peak current densities obtained from panel (A) as a function of H₂O₂ concentration. The line corresponds to the fit to the Michaelis–Menten-like equation (see ESI†).