A novel linear sweep stripping voltammetry was developed for simultaneous determination of trace lead, cadmium,copper and zinc in water samples by the multi-wall carbon nanotube (MWCNT)-Nafion film modified glassy carbon electrode (GCE). The experimental parameters such as supporting electrolyte and buffer pH, the amount of MWCNT-Nafion suspension,accumulation potential and time, were optimized. The results showed that the stripping peaks appeared at - 1.04 V for zinc, -0. 72 V for cadmium, -0. 45 V for lead and -0. 16 V for copper respectively after 5 min accumulation at - 1.20 V in pH 4.0 NaAc-HAc buffer. Satisfactory linearity of the calibration curves of four elements were obtained, the relative standard deviations of the results were less than 5.4％. The method has been applied to simultaneous determination of trace level of lead, cadmium,copper and zinc in water samples with satisfactory results and the recoveries are between 93.3 and 106. 7％.%通过多壁碳纳米管-Nafion复合膜修饰电极,建立水样中痕量铅、镉、铜、锌同时测定的线性扫描溶出伏安分析法,优化支持电解质及pH值、修饰剂用量、富集电位及时间等测定条件.实验结果表明,在pH 4.0的NaAc-HAc缓冲液中,-1.20V富集5min后,在电位-1.04V、-0.72V、-0.45V及-0.16V附近分别产生锌、镉、铅、铜的灵敏溶出峰,测定各元素的线性关系良好,相对标准偏差均小于5.4%.该法已成功应用于实际水样中痕量铅、镉、铜、锌的同时测定,加标回收率在93.3%～106.7%之间,结果满意.
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