Differential pulse anodic stripping voltammetric determination of traces of tin using a glassy carbon electrode modified with bismuth and a film of poly(bromophenol blue)

We report on an anodic stripping voltammetric method for the determination of tin using a glassy carbon electrode modified with bismuth and poly(bromophenol blue). After an accumulation time of 60 s at −1.20 V (vs. SCE), the response of the electrode to tin in 1.0 M HCl is linear in the concentration ranges from 20 nM to 1.0 μM, and from 1.0 μM to 20 μM, with a detection limit of 7.0 nM (at an SNR of 3) and with relative standard deviations in the order of 3.0–3.8%. The method was validated by comparing the results with those obtained by AAS and successfully applied to the determination of tin in canned food. Figure Differential pulse stripping voltammetric responses of Sn 2+ at Bi/Poly(BPB)/GCE in 1.0 M HCl . Sn 2+ concentration (μM): 0.020, 0.10, 0.30, 0.50, 0.70, 1.0, 3.0, 5.0, 7.0, 10.0 and 20.0. Inset: Differential pulse stripping voltammograms of circle portion at low Sn 2+ concentration are zoomed in.