电感耦合等离子体质谱仪截取锥离子传递效率的探讨

电感耦合等离子体质谱仪(ICP-MS)是目前元素痕量检测中最有效的分析仪器之一,但接口传递效率及基质干扰仍困扰仪器性能的进一步提高。借助于激光诱导荧光技术,搭建了用于研究接口界面传递分析物离子的实验装置。通过计算锥口前后离子荧光信号强度变化,探讨了不同实验条件下的截取锥传递效率。结果表明截取锥离子传递效率大大低于理想截取过程;电感耦合等离子体(ICP)射频功率的变化对截取锥传递效率影响不大,但雾化气流速及第一真空区压力的升高,都使截取锥效率传递效率降低。该结果为接口设计改进及仪器整体性能的提高提供了理论支持。

Discussion on ion transmission efficiency in skimmer cone of inductively coupled plasma mass spectrometer

The inductively coupled plasma mass spectrometer (ICP-MS) is one of the most effective analytical instrument in trace elements analysis. However, the interface transmission efficiency and matrix interference still limit the further improvement of instrumental performance. An experimental setup was established based on laser induced fluorescence technology to investigate the analyte ion transmission efficiency at interface. The change of signal strength of ion fluorescence before and after skimmer cone was calculated. The transmission efficiency of skimmer cone under different experimental conditions was discussed. The results showed that the ion transmission efficiency of skimmer cone was much lower than the ideal skimming process. The variation of ICP radio-frequency power had little influence on the transmission efficiency of skimmer cone, but the transmission efficiency of skimmer cone would both be decreased when the flow rate of atomization gas and the pressure at the first vacuum region increased. The study provided theoretical support for the modification of interface design and the improvement of overall performance of instrument.