Fig. 6
Influences of pH value on the oxidation peak potential (a) and oxidation peak current (b) of 1.0 mM AA, 20 μM DA and 50 μM UA obtained at PVP-GR/GCE, respectively. The scan rate was 100 mV s−1. The concentration of PBS was 0.1 M (pH 6.0). Error bars represent SD, n = 3