浅析电感耦合等离子质谱法测定铅和镉内标元素优化

Analysis on the internal standard elements optimization of determination of lead and cadmium by ICP-MS

采用质量数相近的^(113)In、^(115)In和^(103)Rh作为内标元素同时校正元素镉,其中内标元素^(115)In和^(103)Rh校正后元素镉各同位素测定结果均合格,与参考值相对误差控制在10%以内。且采用质量数相近的^(185)Re、^(187)Re和^(209)Bi作为内标元素同时校正元素铅,元素铅各同位素测定结果均合格,与参考值相对误差控制在5%以内,其中高丰度的铅元素测定结果最好。因此选择^(115)In和^(103)Rh、Re和^(209)Bi作为内标元素分别校正铅和镉,曲线线性均达到了0.999以上,准确性和精密性有了不错的提升,具有很好的基体补偿作用和稳定性。

The ^(113)In、^(115)In and ^(103)Rh with similar mass number were used as internal standard elements to correct Cadmium at the same time.The results of each isotope determination of Cadmium were qualified after the correction of the ^(115)In and ^(103)Rh,and the relative error with reference value was controlled within 10%.Meanwhile,The ^(185)Re、^(187)Re and ^(209)Bi with similar mass number were used as internal standard elements to calibrate the element lead at the same time.The results of isotopic determination of element lead were all qualified,and the relative error with reference value was controlled within 5%,among which the results of determination of the high abundance Lead element were the best.Therefore,^(115)In and ^(103)Rh,Re and ^(209)Bi are selected as internal standard elements to correct the Lead and Cadmium respectively.The curve linearity is above 0.999,the accuracy and precision are improved,and the matrix compensation function and stability are very good.