Figure 11: Differential pulse voltammograms of UA (0.1mM, 0.2mM, 0.3mM, 0.4mM, 0.5mM) in 0.2M phosphate buffer solution of pH 7.0 in the presence of 20 μM UA at GMMCPE with the Scan rate of 100 mV/s. (a) The plot shows anodic peak current (Ipa) versus DA concentration.