Highly Sensitive Amperometric α-Ketoglutarate Biosensor Based on Reduced Graphene Oxide-Gold Nanocomposites

Figure 3

(a) CVs and (b) EIS of the different electrodes: bare GCE (A), rGO/GCE (B), Au_nano/GCE (C), and rGO-Au_nano/GCE (D) in 0.1 M KCl containing 5.0 mM [Fe(CN)₆]^3−/4− at a scan rate of 50 mV·s⁻¹. (c) CVs of the different working electrode in the presence of 0.5 mM NADH at a scan rate of 50 mV·s⁻¹. (d) CVs of rGO-Au_nano/GCE in 0.5 mM NADH at various scan rates (from inner to outer: 30, 40, 50, 60, 70, 80, 90 and 100 mV·s⁻¹). Inset: the plot of anodic peak current against the square root of the scan rate.

(a)

(b)

(c)

(d)