Voltammetric detection of antimony in natural water on cathodically pretreated microcrystalline boron doped diamond electrode: A possibility how to eliminate interference of arsenic without surface modification

Very simple and fast electroanalytical method for the detection Sb(III) on chemically unmodified boron-doped diamond electrode (BDDE) has been developed. Voltammetric behavior of antimony was investigated in various acidic supporting electrolytes and the most suitable medium for the determination of Sb(III) on bare BDDE has been 6 mol L-1 HClO4 solution. The analytical performance was studied with differential pulse anodic stripping voltammetry (DPASV) with optimized conditions (deposition potential -1 V vs. Ag/AgCl and deposition time 240 s). An analysis of possible effects due to the presence of other metal ions (especially As(III)) in the solution was eliminated using NaH2PO4 as supporting electrolyte with addition EDTA as selective complexing agent for Sb(III). Speciation of antimony was also investigated. The detection limit of this analytical strategy achieved value of 1.08 x 10(-7) mol L-1. The proposed method was validated and applied for natural water from former antimony mines as real samples.