Determination of Trace Tin by Anodic Stripping Voltammetry at A 1-(3-Nitrophenyl)-3-(4-phenylazophenyl)triazen Modified Carbon Paste Electrode
A new method for the determination of trace tin(Ⅱ) was described.In this study,a 1-(3-Nitrophenyl)-3(4-phenylazophenyl) triazen(m-NPPAPT) modified carbon paste electrode was prepared and the adsorptive stripping voltammetric behavior of tin(Ⅱ) at the modified electrode was investigated.It was found that in 0.5mol / L HCI solution,a coordination compound formed by m-NP-PAPT with tin(Ⅱ).The compound was accumulated and reduced on the surface of the modified elec-trode at -1200 mV.When scanning linearly was from -1200 mV to -200 mV at a scan rate of 150mV / s,the sensitive anodic stripping peak appeared at -476mV(vs.SCE).The sensitivity of the modified electrode in the determination of tinⅡincreased about eleven-fold.The linear range was found to be 4.0×10 -10-1.0×10 -8 mol / L and 1.0×10 -8-4.0×10 -6 mol / L.The detection limit was 2.7×10 -10 mol / L(S / N=3) for 120saccumulation.The proposed method was satisfactorily applied to the determination of trace tin(Ⅱ) in cans food.