湿法消化-石墨炉原子吸收法测定贝肉中镉含量的条件优化

Optimization for Determination of Cadmium in shellfishes by Wet Digestion and Graphite Furnace Atomic Absorption Spectrometry

摘要:

采用湿法消化-石墨炉原子吸收光谱法测定贝肉中的镉含量。将干法灰化和湿法消化两种样品前处理方法进行对比，并研究几种常用基体改进剂对贝肉中镉原子吸收信号的影响，优化了灰化温度和原子化温度，建立湿法消化-石墨炉原子吸收光谱测定贝肉镉的方法。结果表明：采用0.2%的钯标准溶液作为基体改进剂，吸入量6 μL，在灰化温度700 ℃，原子化温度1100 ℃条件下检测，方法的检出限0.057 μg/L，相对标准偏差RSD为0.20%，湿法消化法加标回收率96.83%~100.18%。该方法检出限低，线性关系好，精密度和准确度均满足于贝类样品的测定。

Abstract:

The contents of cadmium in shellfishes were detected by wet digestion-graphite furnace atomic absorption spectrometry. Dry ashing and wet digestion, the two pre-treated methods were contrasted, and the effects of some matrix modifiers on the atomic absorption signals of cadmium in shellfish were studied, the ashing temperature and atomic temperature were optimized, the method of determination of cadmium in shellfish by using wet digestion-graphite furnace atomic absorption spectrometry was established. The results showed that: the detection limit of this method was 0.057 μg/L, RSD was 0.20%, spike recoveries were between 96.83% and 100.18%, under the condition of 0.2% Pd solution as matrix modifier with the volume of 6 μL, ashing temperature was 700 ℃, and the atomic temperature was 1100 ℃. This method could be used to determinate cadmium in shellfish.