Abstract:

Precise and accurate determination of Europium concentration in geological sample using Inductively Coupled Plasma Mass
Spectrometry (ICP-MS) is hindered by severe spectroscopic overlap of BaO + and BaOH + ions. Correction for Eu concentration
mathematically based on precise determination of (BaO+ +BaOH+)/Ba ratios is an applicable method. However, whether the ratios vary
with varying matrix and Ba concentrations remain uncertain. In the current study, we investigated variations in (BaO+ +BaOH+ )/Ba
ratios in solutions by changing matrix and Ba contents in analyzed solutions. The results show that during the course of measurement,
when keeping constant the matrix in solutions, the ratios are almost invariant at different Ba concentrations. In contrast, the matrix ofsolution has a major impact on the (BaO+ +BaOH+)/Ba ratios. Corrected Eu concentrations using the (BaO+ +BaOH+)/Ba ratios
obtained are comparable to results obtained using high resolution mode（R=10000）, with replicate analysis showing good
reproducibility. The results show that using matrix-matching solution is essential for mathematical correction of Eu concentration.

Key words: europium, geological samples, inductively coupled plasma mass spectrometry barium interference, matrix-matching