Itwas found that when pH is increas

It
was found that when pH is increased up to 3.2–3.8 the peak current increases, and at pH higher than 4.0 it decreases rapidly. The pH value of
3.6 was chosen for further analysis. In order to keep the composition
of the buffer constant when studying the effect of pH, Britton Robinson
buffers were used. However, as pH 3.6 was chosen as optimum, acetate
buffer was selected as a suitable electrolyte for this study