3.2. Applying of HPSAM
In order to test applicability of HPSAM to the simultaneous
determination of Sb(III) and Sb(V), the kinetic curves for each of
them and for the mixture of them are drawn (Fig. 3). As can be
seen in Fig. 3, when Sb(V) is selected as the analyte, there are several
pairs of times that Sb(III) has the same currents values in these
pairs of times. The pair of time, which gives the highest accuracy,
is selected for further work. The criteria for choosing the optimum
time pair are as follows. The best pair of time should give the greatest
slope increment[36] and also the change in peak current related
to Sb(III) concentration is negligible. For this reason the time pair
5 and 14 min is employed for obtaining the highest accuracy. Fig. 4
is a sample of H-point standard addition calibration curve which is
constructed at two selected times.