电感耦合等离子体质谱直接测定冰芯样品中痕量铅

摘要

利用电感耦合等离子体质谱仪对冰芯样品中超痕量Pb进行了直接测定。确定了测定溶液中浓度为ng/L级Pb的最佳仪器参数，载气流速、进样速度等与灵敏度之间的关系,浓度和扫描参数对分析精度的影响。仪器对Pb的质量浓度在20～100ng/L的分析精度(RSD，n=3)＜10%,标准加入回收率在85%～115%，检测下限为0.62ng/L，并给出了采自可可西里马兰冰川M3冰芯中Pb的分析结果。%A new method for determination of trace Pb in ice core samples by ICP-MS was developed in this laboratory. The instrument parameters for determination of Pb in ng/L level were optimized. The effects of flow rate of sample gas and auxiliary gas, sampling rate, scan parameters as well as analyte concentration on sensitivity and precision were studied. The detection limit of the method for Pb is 0.62 ng/L. The recovery of standard addition was in the range of 85%～115% with precision (RSD) of less than 10% (n=3). The method has been applied to the determination of trace Pb in Malan M3 ice core samples from Kekexili of Qinhai province.