微波消解-火焰原子吸收法测定生姜中Cu,Mn,Zn,Cd微量元素

Determination of trace elements(Cu,Mn,Zn,Cd) in ginger by methods of microwave sample digestion and flame atomic absorption

目的：本试验以生姜为原料,采用湿法消化和微波消解两种方法处理样品;用火焰原子吸收法测Cu,Mn,Zn,Cd等4种微量元素的含量。方法：通过对混酸体系、混酸比例、固液比例和消化时间等单因素试验确定最佳单因素水平并做正交试验,确定了微波消解和湿法消化的最佳条件;然后采用火焰原子吸收光谱法测定生姜中Cu,Mn,Zn,Cd等微量元素的含量。结果微波最佳消解条件：Cu是HNO3-H2O2为2∶1,固液比例1∶12,消解时间为14 min;Mn是HNO3-HCl为6∶1,固液比例为1∶8,消解时间为12 min;Cd是HNO3-H2SO4为2∶1固液比例为1∶12,消解时间为14 min;Zn是HNO3-HCl为2∶1,固液比例为1∶12,消解时间为12 min。测得生姜中Cu、Mn、Zn、Cd含量分别为3.41,53.07,40.86,5.15μg/g;回收率为95.26%~108.0%之间,精密度为0.2377%~1.258%之间。结论：微波消解法消解样品,具有快速、简便、经济、消解完全等特点。

Purpose： This test is to analyze the sample,ginger by methods of Wet Digestion and Microwave Digestion,and to determine the content of the four trace elements,Cu and Zn,Cd,and Mn by the means of atomic absorption spectrometry.Method： After the single factor test of mixed acid system,mixed acid ratios,the solid-liquid ratio and digestive time,we are to determine the best single factor levels and carry out the orthogonal experiment in order to ascertain the best condition for wet digestion and microwave digestion adopting the atomic absorption spectrometry;and the next step is to determine the content of trace elements Mn,Cu and Zn,Cd,etc.Results： The best condition for microwave digestion of HNO3-H2O2,Cu is 2∶1,solid-liquid ratio 1∶12,best period for digestion is 14 mins;as for Mn,HNO3-HCl is 6∶1,solid-liquid scale is 1∶8,period for clearing up is 12 min;for Cd,HNO3-H2SO4 is 2∶1,solid-liquid scale is 1∶12,digestion period is 14 min;for Zn,HNO3-HCl is 2∶1,solid-liquid scale is 1∶12,period for clearing up is 12 min.Content of measured in ginger,Cu and Zn,Cd,Mn concentration is repectively 3.41,53.07,40.86,5.15 μg/g;the recovery rate is 95.26%～108.0%,accuracy is 0.2377%～1.258%.Conclusion： The sample can be digested byt the way of microwave digestion fast and easily,economically,and cleared up fully.