微波消解-石墨炉原子吸收法检测乳粉中的铬

Detection of Chromium in Milk Powder by Microwave Digestion Instrumentand Graphite Furnace Atomic Absorption Spectrometry

目的 探讨用石墨炉原子吸收法检测乳粉中铬含量的最佳试验条件。方法 将乳粉在微波消解仪中消化后,采用塞曼校正,石墨炉原子吸收光谱法自动进样测定样品中铬含量。结果 方法线性范围为铬含量0.0~20.0μg/L,回归方程为^Y=0.028 5 X＋0.069 2,线性系数0.999 0,检出限0.59μg/L;加标回收率为95.40%~104.00%;RSD值为0.40%~5.06%。结论 样品经过微波消解、赶酸、去离子水定容后可直接石墨炉自动进样检测,该法线性好,回收率高,变异小,操作简单,可用于乳粉中铬含量测定。

Objective To explore the optimal experimental powder by graphite furnace atomic absorption spectrometry. conditions in detecting content of Chromium （Cr） in milk Methods The samples were detected in AAS with auto- matic sampling system,using zeeman for background correction after microwave digestion. Results The linear range of the method was 0-20.0 μg/L. The linear regression equation and correlation coefficient was Y=-0. 028 5 X ＋0. 069 2 and 0. 999 0,the detection limit was 0.59 μg/L,standard rate of recovery was 95.40%-104.00%, RSD value was 0.40%- 5.06%. Conclusion The content of Cr in samples can be detected directly by Atomic Absorption Spectrometry （AAS） after microwave digestion. The method of AAS is suitable for detecting the content of Cr in milk powder with the advanta- ges of good linearity,high rate of recovery, small variation and simple procedure.