石墨炉原子吸收光谱法测定甜菜块根中铅和镉

Determination of Pb and Cd in Beet Root with GFAAS

利用微波消解-石墨炉原子吸收光谱法对编号为GBW07604、GBW07601的质控样及10个甜菜块根样品进行重金属铅、镉的检测,并且对这两种金属元素的最低检出限、精确度、准确度及样品差异进行分析。结果表明,在本实验条件下,铅的最低检出限为1.33μg/kg,镉为0.05μg/kg。铅浓度范围在0.0～80.0μg/L时,与其吸光度呈良好的线性关系,线性方程为y=-0.000021x2+0.00666x+0.0206,线性系数r=0.9991;镉浓度范围在0.0～3.0μg/L时,与其吸光度也呈良好的线性关系,线性方程为y=-0.019596x2+0.20565x+0.0259,线性系数r=0.9997。不同样品间存在一定差异,但变化不大,没有达到极显著水平。实验表明,本方法及仪器条件适合甜菜块根样品中铅、镉的检测。

Two quality control samples, GBW07604 and GBW07601, and 10 beet root samples were used to determine Pb and Cd by microwave digestionb - graphite furnace atomic absorption spectrometry （GFAAS）. The lowest detection limit, accuracy and variance of the two elements were analyzed. The results showed that the lowest detection limit of Pb and Cd were 1.33μg/kg and 0.05μg/kg, respectively. The concentration range of Pb was 0.0μg/L-80.0μg/L, there was a linear relationship with absorbance, the linear equation： y=-0.000021x^2＋ 0.00666x＋0.0206 （r=0.9991）. The concentration range of Cd was 0.0μg/L-3.0μg/L, there was a linear relationship with absorbance, the linear equation： y=-0.019596x^2＋0.20565x＋0.0259 （r=0.9997）. There was no significant difference among the samples. The result indicated that the method and apparatus condition were suitable for the detection of Pb and Cd.