The dependence of anodic peak currents with the preconcentration
time for 80 pmol/L Ag(I) was also investigated. As can be
seen in Fig. 3, the peak current was found to increase linearly with
increasing the accumulation time up to 300 s and then remained constant probably due to the surface saturation [25]. Therefore the
preconcentration time of 300 s was used for all subsequent measurements.