Abstract

Poster Presentations

Day 2, May 12（Tue.）　　Poster (1008/09)

2P-35　　PDF

Impacts of Coexisting Metal Ions on Copper Isotopic Ratio Measurement using Multiple Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS)

(Univ. Tokyo)
^oKota Yamamoto, Takafumi Hirata

Simultaneous detection of multiple isotope signals using multiple collector-ICP-Mass spectrometry (MC-ICP-MS) can minimize fluctuations in the ion source and achieve isotopic ratio measurement precision better than 0.1 ‰. Recent studies revealed that the isotopic ratio of Cu in biological samples varies by reflecting changes of nutritional states or disorder. To use the changes of the isotopic ratios as diagnostic marker, high precision in the ⁶⁵Cu/⁶³Cu isotopic ratio measurements is highly desired. However, great care must be given in both mass spectrometric interference and non-mass spectrometric interference. Our doping experiments suggested that the presence of Na can cause mass spectrometric interference on ⁶³Cu⁺ by ²³Na⁴⁰Ar⁺. Since Na is one of the major nutrients in biological tissues, separation of Na with high recovery of Cu is required. To obtain reliable Cu isotopic ratio data from biological samples, Cu was separated from various coexisting elements (e.g., Na, Mg, K, Ca and Fe) through a chemical purification procedure using anion exchange chromatography. Moreover, external correction technique using Zn was also applied for the ⁶⁵Cu/⁶³Cu ratio measurements. In this presentation, the effect of external correction technique using Zn isotopes, together with contribution of non-mass spectrometric interferences by coexisting elements, will be discussed.