ICP-AES中基体干扰效应及其机理研究——Ⅰ.基体干扰效应的一般分布规律

MATRIX EFFECTS AND THEIR MECHANISMS IN INDUCTIVELY COUPLED PLASMA ATOMIC EMISSION SPECTROSCOPY Ⅰ. General Distributions of Vertical Profiles of Matrix Effects

本文以Na、ca、Al、Zn作为主要基体元素,在不同ICP发射光谱仪上考察了20多条分析谱线受到的干扰情况,初步总结了基体干扰效应的一般规律。结果表明,在常用分析条件下,一般金属元素具有与易电离元素类似的基体效应,即在较低观察区域对测定谱线信号产生增感,而在正常观察区域产生抑制;从增感转向抑制的零干扰点主要出现在感应圈上方8～14mm的观察区域,这一结果为实际分析条件的优化提供了有益的依据。

Na, Ca, Al, Zn have been selected as the major matrix elements to study matrix effects in ICP-AES. Matrix effects on more than 20 analyte lines with different spectrometers were studied. It was shown that most of the matellic matrix elements (MME) have similar influences on analyte emission as the alkali. In general, the existance of excess MME enhances analyte emission in the lower regions of analytical channel of the plasma for both atom and ion lines, but depresses the emission for both atom and ion lines in the normal obsevation regions. It was shown that the 'non-interference' points from enhancement to depression of matrices on analyte signals appeared in the region of 8mm to 14mm above the load coil under conventional operating conditions. The results would be useful for the optimization of operating conditions.