薄荷中微量元素的测定

Determination of Trace Elements in Mentha arvensis

用电感耦合等离子体原子发射光谱法 (ICP -AES)同时测定了薄荷的叶、茎和整株三部分中微量元素的含量 ,样品处理分别采用干法和微波消解法。并对干法和微波消解法的测定结果进行了比较。结果表明 ,薄荷中含有Al、Fe、Na、Zn等多种微量元素 ,其中Cu、Fe、Mn、Ni、Zn、Sr等是人体必需微量元素。干法中某些元素可能因挥发而全部或部分损失 ;某些元素在氯化物大量存在时具有挥发性 ;有些不挥发的元素会因进入坩埚壁而造成损失 ,当灰分体积很小时 ,更突出 ;用酸处理样品时 ,分析元素会因灼烧而难以溶解。微波消解法损耗的元素较少 ,测得的结果较准确。用ICP -AES法测定薄荷中的微量元素具有简单、快速、准确度高的优点。

The dertermination of trace elements in Mentha arvensis including its leave,stem and the whole by using inductively coupled plasma-atomic emission spectrometry was presented.The sample was made in dry-ashing and microwave methods.The dertermination results indicate that Mentha arvensis contains many trace elements such as Al,Fe,Na,Zn,etc.Among them Cu,Fe,Mn,Ni,Zn,Sr are necessary for the health of human beings.Comparison was made between the two treatment methods.In dry-ashing method some elements may lose as a whole or as a part for volatilizing.Certain elements are volatile when existing in chloride as a large amount.Some elements without volatilzation may lose ,especially in the case of little ash.It is hard to fuse by burning when dealt by acid.Elements lost less in microwave method,and result is more exact.So ICP-AES method was characterized with simple,fast and high accuracy for the determination of trace elements in Mentha arvensis.