双硫腙修饰丝网印刷电极同时检测茶汤中的Cu(II)和Pb(II)

Simultaneous Detection of Copper and Lead ions Using Dithizone Modified Screen-printed Electrode

摘要:

在乙酸-乙酸钠缓冲溶液（0.1 mol/L、pH 5.0）中，利用双硫腙修饰丝网印刷电极阳极溶出伏安法分别于-0.18 V、-0.76 V阳极溶出峰同时测定重金属离子Cu2+和Pb2+。通过优化测定条件，得到最佳参数为：双硫腙修饰量3 μg、pH 5.0、富集电位-1.1 V、富集时间210 s。在此条件下，Cu2+和Pb2+浓度分别在1.0×10－10~1.0×10－5 mol/L、1.0×10－10~1.0×10－6 mol/L范围内与峰电流呈良好的线性关系（RCu=0.9991，RPb=0.9934），检测限分别为0.35×10-10 mol/L、0.41×10-10 mol/L。该方法简单、快速、灵敏，可用于检测茶汤中的Cu2+和Pb2+。

Abstract:

The contaminant metal copper and lead ions were determined simultaneously using dithizone modified screen-printed electrode (SPE) by anodic stripping voltammetry (ASV) in the HAc-NaAc buffer solution (0.1 mol/L, pH 5.0). Copper and lead ions had sensitive anodic stripping peak at -0.18 V and -0.76 V, respectively. The optimum parameters by optimizing the conditions of the detecting method were as follows, dithizone modification quantity 3 μg, pH 5.0, electrodeposition potential -1.1 V and electrodeposition time 210 s. Under the optimum conditions, a good linear retationship was obtained between the concentration of Cu2+ and Pb2+ ranged in 1.0×10-10~1.0×10-5 mol/L and 1.0×10-10 -1.0×10-6 mol/L, respectively, with stripping peak current (RCu = 0.9991, RPb = 0.9934). The detection limits for Cu2+ and Pb2+ were of 0.35×10-10 mol/L and 0.41×10-10 mol/L, respectively. The method was simple, fast and sensitive for the determination of Cu and Pb in tea.