ポスター発表
- 第2日 5月12日（火） P会場（1008/09）
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2P-35 PDF
多重検出器型ICP質量分析計を用いた銅同位体比測定における共存元素の影響
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.