The possibility of applying antimony-film modified glassy carbon electrode in sequential-injection analysis
(SIA) was investigated with the objective of determining Pb(II) and Cd(II) by anodic stripping
voltammetry (ASV). The conditions of antimony-film deposition concerning composition of the plating/
carrier solutions, concentrations of Sb(III) and hydrochloric acid, effects of different supporting
electrolyte salts, and plating potential were optimized. It was found that the antimony-film deposition
on glassy carbon substrate in a sample solution consisting of 750gL−1 Sb(III), 0.5 mol L−1 HCl at −1.5V
(vs. Ag/AgCl/3 mol L−1 KCl) yielded a modified electrode suitable for the determination of Pb(II) and Cd(II)
at the gL−1 level. The reproducibility of the analytical signals was characterized by a relative standard
deviation lower than 2.8%, and the calculated values of detection limits were 1.2gL−1 for Pb(II) and
1.4gL−1 for Cd(II). The presence of KSCN in the sample solution offers the possibility of detecting ions
with more negative oxidation potentials like Zn(II), Mn(II) or Cr(III). The developed SIA-ASV procedure
was compared with the commonly used batch method, and its applicability was tested on a spiked tap
water sample.