微波消解-石墨炉原子吸收光谱法连续测定水果和蔬菜中铅铬镉

建立了用微波消解样品，石墨炉原子吸收光谱法在同一体系中连续测定水果和蔬菜中重金属铅(Pb)、铬(Cr)、镉(Cd)的方法。研究了消解试剂、消解温度和时间对样品消解效果的影响，优化了石墨炉原子吸收光谱法测定条件。在最佳实验条件下，Pb、Cr、Cd 的线性范围分别为0 ～40、0 ～80、0～3μg/L，检出限分别为0.293、0.037、0.850μg/L，相对标准偏差为2.1%～5.3%，回收率为95.0%～101.9%。用于实际样品测定结果令人满意。

Continuous Determination of Lead,Chromium and Cadmium in Fruit and Vegetable by Microwave Digestion-Graphite Furnace Atomic Absorption Spectrometry

An effective method was developed for continuous determination of Pb, Cr and Cd in fruit and vegetable by using graphite furnace atomic absorption spectrometry (GFAAS) with microwave digestion. The effects of digestive reagent, digestion time and temperature on sample preparation were discussed, and the determination conditions by GFAAS were optimized. Under the optimum conditions, the linear ranges of Pb, Cr and Cd were 0 to 40 μg/L, 0 to 80 μg/L and 0 to 3μg/L and their detection limits were 0.293 μg/L, 0.037 μg/L and 0.850 μg/L, respectively. The precision relative standard deviations were between 2. 1% and 5.3% for determining the above three elements in flowering Chinese cabbage and snow pear by this method, and the spike recoveries range from 95.0% to 101.9%.