采用微波消解,电感耦合等离子体质谱法测定海产品中铅含量及其同位素比. 通过选择本底铅浓度低的硝酸降低背景值,选择合适内标以减少仪器波动带来的误差,使得该方法在0 μg/L~100 μg/L范围内线性良好,204 Pb、206 Pb、207 Pb和208 Pb的方法检出限为0. 041 μg/L ~0. 180 μg/L. 用该方法测定有证标准物质,结果在标准值范围内,海产品样品6次测定结果的 RSD 为3. 1% ~8. 6%,加标回收率为89. 9% ~96. 3%. 26 种海产品中总铅质量比为0. 018 mg/kg ~2. 32 mg/kg,铅同位素 207 Pb/ 206 Pb值为0. 783 55~0. 881 61.%A method of detecting the concentration of lead and ratio of lead isotopes in sea products via mi-crowave digestion-inductively coupled plasma mass spectrometric analysis was built. Nitric acids were selected according to reagent blank in order to reduce lead concentration brought by nitric acids. Error of instrument fluc-tuations was decreased by choosing suitable internal standards, linearity of standard cruve was good at 0 μg/L~100 μg/L. Detection limits of this method for 204 Pb、206 Pb、207 Pb and 208 Pb were ranged from 0. 041 μg/L to 0. 180 μg/L respectively. By analysis with this method, lead concentration of reference material GBW08571 and GBW10068 were 1. 90 mg/kg and 1. 22 mg/kg,and relative standard deviation were 2. 3% and 3. 6%; isotope ratio (207Pb/ 206Pb) of NB S981 was 0. 913 53 with relative standard deviation 3. 8%;relative standard deviation ( precision) of lead in sea products was 3. 1% ~8. 6%,and recovery of standard addition was 89. 9% ~96. 3%;lead concentration and isotope ratio(207Pb/ 206Pb) in 26 kinds of sea products were 0. 018 mg/kg~2. 32 mg/kg, 0. 783 55~0. 881 61 separately.
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