石墨炉原子吸收光谱法测定水果和蔬菜中的痕量铅镉

目的 建立水果和蔬菜中铅镉的石墨炉原子吸收光谱测定法。方法 样品加入硝酸-过氧化氢消解液后放置过夜，次日直接在智能样品处理器上进行低温赶酸。采用石墨炉原子吸收光谱法测定。结果 铅和镉浓度分别在0～20 ng/ml和0～2 ng/ml范围内线性相关系数分别为0.9989和0.9986，检出限分别为0.76 μg/L和0.033 μg/L，RSD在2.16%～4.90%之间，加标回收率在90.0%～98.3%之间。结论 该方法空白值低，简单易行，灵敏度高，准确性好，适用于水果蔬菜中铅和镉的快速测定。

Rapid determination of trace lead and cadmium in fruits and vegetables by graphite furnace atomic absorption spectrometry

Objective This work was to establish a method for determining lead and cadmium in fruits and vegetables by graphite furnace atomic absorption spectrometry. Methods The mixture of nitric acid-peroxide hydrogen was added into the sample and stand overnight, then the acid was removed at low temperature using intelligent sample processor. The contents of lead and cadmium were determined by GFAAS. Results The method showed good linear correlation with lead level in the range of 0ng/ml～20ng/ml (r=0.9989) and with cadmium in the range of 0ng/ml～2ng/ml (r=0.9986). The detection limits were 0.76μg/L and 0.033μg/L for lead and cadmium, respectively. RSD was within 2.16%～4.90%, and the recovery was within 90.0%-98.3%. Conclusion This method has low backgroud, is easy to use, sensitive, and accurate. Therefore, it could be applied to determinine trace level of lead and cadmium in fruits and vegetables.