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本文对ICP -AES法测定食品中Al、B、Ca、Cu、Fe、K、Mg、Mn、Na、P、S、Sr和Zn的 5种样品消化方法进行了评价 ,五种方法包括 50 0℃干灰化法、HNO3-HClO4湿消化法、HNO3微波消化法、HNO3-H2 O2 微波消化法、HNO3-H2 O2 -HF微波消化法。在HNO3-H2 O2 -HF微波消化法中 ,应用氧化硅(Ⅳ )除去过剩的HF ,使之能够同时准确测定元素Al、B和其它常见元素。应用上述消化方法对国家标准技术研究院 (NIST)的 7个标准参考物质进行分析 ,比较了 1 3个元素的回收率。结果表明 :在HNO3-H2 O2 -HF微波消化法中 ,1 3个元素的回收率均很好 ,牡蛎组织、牛肝、和菠菜中的Al除外 ,绝大多数元素应用 3种微波消化法的测定值很接近。值得注意的是 ,在选定的元素中除Al、B外 ,HNO3-HClO4湿消化法是最简单有效的样品处理方法 ;尽管干灰化法有几点需要注意 ,但当样品仅是测定不挥发元素且含量较低时 ,该法则是一个较好的方法。
In this paper, five kinds of sample digestion methods for determination of Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Sr and Zn in food by ICP-AES were evaluated. ℃ dry ashing, HNO3-HClO4 wet digestion, HNO3 microwave digestion, HNO3-H2 O2 microwave digestion, HNO3-H2 O2-HF microwave digestion. In HNO3-H2 O2 -HF microwave digestion, silicon oxide (IV) is used to remove excess HF, enabling simultaneous accurate determination of the elements Al, B and other common elements. Seven standard reference materials from the National Institute of Standards and Technology (NIST) were analyzed using the above digestion method and the recoveries of 13 elements were compared. The results showed that the recoveries of 13 elements in the HNO3-H2 O2 -HF microwave digestion method were very good except oyster tissue, beef liver and spinach, most of the elements were detected by three kinds of microwave digestion The measured value is very close. It is worth noting that the HNO3-HClO4 wet digestion method is the simplest and most effective method for sample processing except for Al and B in the selected elements. Although dry ashing requires a few observations, Volatile elements and low levels, the law is a better method.