(a)

(b)

Figure 3: Cyclic voltammograms of ferritin on a 6 cm2 bare gold electrode. Ferritin equilibrated at zero potential or at −200 mv, (a). Ferritin adsorbed at +500 mv, (b). The voltage was cycled at 100 mV/s in 0.05 M MOPS pH 7 with 0.05 mM TGA as promoter.