悬浮液进样-火焰原子吸收光谱法测定桑叶中的微量元素

摘要

[Objective] The research aimed to determine the trace elements in the mulberry leaves by the suspension sampling - flame atomic absorption spectrometry. [ Method] After the drying, grinding and sifting, the mulberry leaves sample was suspended in 0.30% agar solution. It became the homogeneous suspension by the ultrasonic dispersion. The flame atomic absorption spectrometry was used to determine the content of trace elements Fe, Mn, Zn, Mg and Ca in the suspension. [Result] The best stabilizer of mulberry leaves sample suspension was 0.30% agar solution, and the optimal added amount of agar solution was 40 ml. The ultrasonic treatment could greatly increase the stability of suspension. 100 ml LaCl3 solution could eliminate the chemical interference. The average values of Fe, Mn, Zn, Mg and Ca in the suspension were respectively 582.32, 70.97, 32.54, 3 977.50 and 3 279.75 μg/g. The recovery rates of every trace element were during 96.4% -105.4%. [Conclusion] The method was fast, easy and had the good precision and accuracy.%[目的]利用悬浮液进样-火焰原子吸收光谱法测定桑叶中的微量元素.[方法]桑叶样品经烘干、粉碎、过筛,悬浮在0.30%琼脂溶液中,超声分散成均匀的悬浮液.火焰原子吸收光谱法测定该悬浮液中微童元素Fe、Mn、Zn、Mg、Ca的含量.[结果]桑叶样品悬浮液的最佳稳定剂为0.30%琼脂溶液,且琼脂溶液的最适加入量为40 ml;超声处理可使悬浮液的稳定性大大增加;10.0 ml LaCl3溶液可消除化学干扰.桑叶样品中Fe、Mn、Zn、Mg、Ca的平均值分别为582.32、70.97、32.54、3 977.50和3 279.75 μg/g;各微童元素的回收率为96.4%～105.4%.[结论]该法快捷、简便、具有良好的精密度和准确度.