单扫描极谱法测定蔬菜中的微量铜

Determination of Trace Copper in Vegetable by Single-scanning Polarography

在pH值为6．8的混合磷酸盐缓冲体系中，Cu（Ⅱ）-乙酰丙酮在-0．325V处（VS．SCE）产生灵敏的络舍物吸附波，Cu（Ⅱ）浓度在0．004—0．40μg／mL范围内与峰电流（I″p）呈良好线性关系，相关系数为0.9961，检出限为1．5μg／L，用该方法测定了蔬菜中微量铜，试样加标回收率为96％～105％，相对标准偏差小于1．6％，该法准确、简便、选择性好。

The sensitive polarographic adsorptive wave of copper （ Ⅱ ） -acetylacetone system was studied in the base solution containing phosphate buffer with pH5.2-5.8. The peak potential is -0.325 V （VS. SCE）. The peak currents with the concentration of Cu （Ⅱ） is linear in the range of 0.004 - 0.40 μg/mL, γ = 0.9961, and the detection limit is 1.5 μg/L. Trace copper in vegetable was determined by this method. The recovery was in 96% - 105% and the RSD was less than 1.6%. This method is accurate, simple, and selective.