Simultaneous Determination of Antimony and Lead in Gunshot Residue by Cathodic Adsorptive Stripping Voltammetric Methods

Differential pulse cathodic adsorptive stripping (DPCAdSV) and square wave cathodic adsorptive stripping (SWCAdSV) voltammetric methods were developed for the determination of antimony and lead in gunshot residues. Linear working ranges for DPCAdSV and SWCAdSV methods were (2.0×10−9–5.0×10−7) M and (2.0×10−9–7.0×10−7) M for antimony and 2.0×10−9–3.0×10−7 M (both methods) for lead. The detection of antimony limits were found to be 1.3×10−9 M for DPCAdSV and 7.3×10−10 M for SWCAdSV while the corresponding values for lead were 3.0×10−9 M and 5.8×10−10 M. Antimony and lead contents obtained by these methods in gunshot residues are in good agreement with those obtained by graphite furnace atomic absorption spectrometric method within a confidence limit of 95%.