ICP–AES法同时检测生蚝中铅、铜、镉、铬、铁含量时3种样品前处理方法比较

采用干法、湿法和微波消解法处理珠海生蚝样品,用电感耦合等离子体发射光谱仪在谱线Pb 220.3 nm,Cu 324.7 nm,Cd 228.8 nm,Cr 283.5 nm,Fe 259.9 nm下测定样品中铅、铜、镉、铬、铁5种重金属元素的含量。结果表明,珠海市4个养殖基地的生蚝重金属含量均在国标限量范围内。铅、铜、镉、铬、铁各元素线性相关系数分别为0.999 8,0.999 4,0.999 9,0.999 2,0.997 8,检出限分别为0.020,0.014,0.001,0.036,0.120 mg/kg。干法、湿法、微波消解法的加标回收率分别为72.8%~99.3%,88.0%~102.0%,89.0%~103.0%。微波消解处理样品,ICP–AES法同时测定4种样品中5种重金属的含量,其测定结果的相对标准偏差均小于17%。微波消解–ICP–AES适合生蚝中铅、铜、镉、铬、铁含量的快速测定。

Comparison of Sample Pretreatment Methods as Simultaneous Determination of Pb,Cu, Cd,Cr,Fe in Oyster by ICP-AES

The content of heavy metals （Pb,Cu,Cd,Cr and Fe） in oysters was analyzed by ICP–AES with dry ashing,HNO3 digestion and microwave digestion. The results showed that the content of heavy metals in four oyster samples did not exceed the standard. Correlation coefficients of Pb,Cu,Cd,Cr,Fe were 0.999 8,0.999 4,0.999 9,0.999 2, 0.997 8,and the detection limits were 0.020,0.014,0.001,0.036,0.120 mg/kg,respectively. The recoveies for dry method, wet method and microwave method were 72.8%–99.3%, 88.0%–102.0%, and 89.0%–103.0%,respectively. The relative standard deviation of determination results of microwave digestion method was less than 17%. It was simple,fast and accurate for rapid determination of trace Pb,Cu,Cd,Cr and Fe in oyster by ICP–AES with microwave digestion.