微波法和湿法消解测定云南红河紫山药中金属元素

Determination of Metal Elements in Dioscorea alata L.of Yunnan Honghe by Microwave Digestion and Wet Digestion

[目的]研究湿法消解和微波消解对紫山药前处理的影响。[方法]分别采用湿法消解和微波消解处理紫山药,利用火焰原子吸收光谱法测定紫山药中的Mn、Co、Cu、Fe、Pb和Zn这6种金属元素。[结果]紫山药中含有丰富的金属元素,2种前处理消解方法对测定紫山药中金属元素含量有一定影响。湿法消解紫山药元素含量从大到小依次为Fe、Cu、Zn、Mn、Co、Pb,而微波消解紫山药元素含量从大到小依次为Fe、Cu、Zn、Co、Mn、Pb。2种前处理方法测得Fe元素含量都是最高,Pb元素含量最少,除Mn和Zn外,微波消解处理测定各元素的含量比湿法消解的略高。对2种消解法进行了加标回收率试验,湿法消解回收率为68.90%～113.87%,微波消解法回收率为91.66%～123.30%。[结论]微波消解法更适用于紫山药金属元素的前处理。

[Objective] The research aimed to study the effects of wet digestion and microwave digestion on pretreatment of Dioscorea alata.[Method]The wet digestion and microwave digestion were employed for the pretreatment of Dioscorea alata,respectively.The contents of six metal elements such as Mn,Co,Cu,Fe,Pb and Zn in Dioscorea alata were measured by flame atomic absorption spectrometry.[Result]Dioscorea alata had abundant metal elements.Two kinds of pretreatment digestion methods had a certain effect on the determination of metal elements in Dioscorea alata.The order of the element content of Dioscorea alata by wet digestion was Fe〉Cu〉Zn〉Mn〉Co〉Pb,while the microwave digestion was Fe〉Cu〉Zn〉Co〉Mn〉Pb.Both of the two pretreatment methods had the highest content of Fe and the least Pb elements.Except for Mn and Zn,the determination of the content of each metal element by microwave digestion was slightly higher than that of the wet method.The standard recovery experiments showed that the recovery was in the range of 68.90%-113.87% for the wet digestion and 91.66%-123.30% for the microwave digestion.[Conclusion]The microwave digestion is the more appropriate pretreatment for the metal elements of Dioscorea alata.