In this paper, electrochemical behavior of Pb2+ at acetylene black/chitosan composite film modified glassy carbon electrode was studied in detail by anodic stripping voltammetry. The experimental conditions such as supporting electrolytes, pH of solution, accumulation potential and acculu-mation time were optimized. Compared with bare glassy carbon electrode, the composite film electrode showed good electrochemical activity for the determination of Pb2+. A sensitive and sharp anodic stripping peak was appeared at -0. 51 V when Pb2+ was added to BR buffer solution (pH 5. 6) . When the acculumation potential was -1. 2 V and the acculumation time was 300 s, the stripping peak currents increase linearly with the concentration of Pb2+ from 2X 10-9-2X 10-7 mol/L and 1X10-6-5X10-5 mol/L. The detection limit was up to 1. 0 X 10-10 mol/L (S/N = 3). This modified electrode showed certain interference resistance to the determination of Pb2+ by anodic stripping voltammetry. The modified electrode was applied to the determination of Pb2+ in actual water sample by standard addition. The results were consistent with those obtained by atomic absorption spectrometry.%利用阳极溶出伏安法详细研究了Pb2+在乙炔黑/壳聚糖膜修饰玻碳电极上的电化学行为,并对各种实验条件如支持电解质、溶液pH值、富集电位、富集时间等进行了优化.相对于裸玻碳电极,Pb2+离子在复合膜修饰电极上具有良好的电化学响应,Pb2+在pH5.6的BR缓冲溶液中,在峰电位-0.51 V处出现一尖锐的阳极溶出峰.当富集电位为-1.20 V,富集时间为300 s时,Pb2+的溶出峰电流与其浓度在2×10-9～2×10 7 mol/L间和1×10-6～5×10-5 mol/L间呈良好的线性关系,检出限可达1×10-10 mol/L(S/N=3).该修饰电极对铅离子的阳极溶出伏安检测还有一定的抗干扰能力,将用该修饰电极应用于实际水样中Pb2+的加标测定,结果与原子吸收光谱法测得结果相一致.
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