Thus,nitrate retention was hindered by the presence of relatively
higher concentrations of perchlorate ions in the sample zone.
Carryover was minimized by inserting a 300-cm long coil
among the sample loop and the column and as showed in
Fig. 2, sensitivity and precision were improved in this condition.
On the other hand, results in Fig. 2 show that the
eluent concentration (initially 0.6 mol L−1) could be reduced
to 0.05 mol L−1, improving sensitivity, minimizing reagent