同位素稀释等离子体质谱法测定岩石中的铂

The Measurement of Pt in Rocks by Isotope Dilution ICP-MS

报道了以普通铂标准溶液标定198Pt稀释剂溶液的浓度,采用同位素稀释等离子体质谱法测定岩石中的Pt。稀释剂标定结果得到该198Pt稀释剂溶液的浓度为19.76μg/g(n=4,RSD=0.16%)。4次测定标准物质GBW07293(取样量约0.5g,推荐浓度440±37ng/g)中Pt含量,结果分别为412.0±2.6ng/g、495.9±2.7ng/g、519.6±3.5ng/g和677.3±3.8ng/g。单份试样重复测量的相对标准偏差<1%。由于铂族元素的块金效应,各份平行测定的结果较分散。

The accurate Pt spike calibration and chemical procedures for sample digestion are reported in this paper. The 198Pt spike was calibrated by isotope dilution with common Pt standard solution. The concentration of 198Pt spike is 19.76 μg/g(n=4, RSD=0.16%). The Pt content in standard reference material GBW 07293 (～0.5 g,the recommended concentration is 440±37 ng/g.) was determined for four times. The results are 412.0±2.6 ng/g, 495.9±2.7 ng/g, 519.6±3.5 ng/g and 677.3±3.8 ng/g.The internal precision of each run is better than 1% RSD. Because of the 'nugget effect' of the platinum group elements, the four results of the standard reference material of GBW 07293 are dispersed. 