用密封微波溶样导数火焰原子吸收法测定奶粉中的锌和铜

Determination of Iron and Zinc in Milk Powder by Closed Vessel Micro wave Digestion and Derivative Flame Atomic Absorption Spectrometry

用密封微波溶样技术对样品奶粉进行了预处理，用导数火焰原子吸收法对其中所含的微量元素锌和铁进行了测定，结果分别为３０．８４和０．２３７９ｍｇ·Ｌ－１。与常规样品消化方法相比较，微波样品处理技术具有方便快捷、污染少、消化完全等特点，而导数测量装置与火焰原子吸收分光光度计的连接使测定的灵敏度锌和铁分别提高了１８倍和１０倍；检出限分别降低了１０倍和２３倍；并获得了良好的精密度。

A new method was developed for the determination of iron and zinc in milk powder,based on the technique of closed-vessel microwave digestion and derivative flame atomic absorption spectrometry.With the aid of a derivative equipment connected with an atomic absorption spectrometer derivative atomic absorption signal as well as conventional signals were obtained simultaneously by a double-pen recorder.The sample was pre-treated by conventional wet ashing and microwave digestion.The results obtained from two digestion methods were compared.The sensitivity and detection limit were improved.The proposed method is simple,rapid,nonpollution and safe.The accuracy and recovery for trace metal analysis are satisfactory