浅析锡对电感耦合等离子体质谱法测定镉的干扰

Study on Interference of Tin in the Determination of Cadmium by Inductively Coupled Plasma Mass Spectrometry

在不同的工作条件下,分析了不同Sn(锡)/Cd(镉)比值下Sn对电感耦合等离子体质谱法(ICP-MS)测定Cd的干扰程度,并将经过在线干扰校正和离线干扰校正后的Cd浓度与标准值比较,实验结果表明:当样品中Sn浓度与Cd浓度比值在2以下时,Sn对Cd的干扰很小,Cd的测定值不用经过任何方式校正也比较接近标准值;当Sn浓度与Cd浓度比值在2~30时,采用离线校正和在线校正后的Cd测定值与标准值均比较接近;当Sn浓度与Cd浓度比值大于30时,采用离线校正才能获得更满意的结果。

The spectral interference level of tin（Sn） in the determination of cadmium（Cd） by inductively coupled plasma mass spectrometry（ICP-MS） was investigated with different concentration ratio of Sn/Cd under different work conditions. The content of Cd was obtained by on-line and off-line interference corrections, respectively, which was consistent with the certified value. The results showed that： the contents of Cd maintained good agreement with the certified value without any interference corrections when the concentration ratio of Sn/Cd was below 2 and the effect of Sn on Cd determination was negligible~ the contents of Cd corrected by on-line and off-line interference were in accordance with the certified value when the concentration ratio of Sn/Cd was in the range 2 ~ 30; satisfactory results were obtained only by off-line interference when the concentration ratio of Sn/Cd exceeded 30.