A technique for separation of Mg, with 101. 6%± 1. 2% yield from wine has been developed for high precision analysis of Mg isotopes by multiple-collector inductively coupled plasma mass spec-trometry. One separate stage of ion-exchange chromatography was carried out using cation exchange resin, AG50W-X8 and elution with 1 mol/L HNO3. A mixture of H2(2. 1 mL/min) and He (7.0 mL/min) was performed to decrease isobars of 12C12C+ , 12C21H+ during Mg isotope analysis by MC-ICP-MS technique along with SSB method. 40 wines were analyzed then. 26 Mg/24 Mg and 25 Mg/24 Mg show significant variation, this implies that Mg can be a good tracer to tracing geographical origin of wine with good geographical resolution. The samples with similar Mg isotopic compositions can be distinguished by the combined technique of Mg isotope analysis with inorganic elements analysis.%建立了阳离子树脂富集镁的方法.以1 mol/L HNO3为淋洗液、AG W50-X8阳离子树脂富集镁.方法回收率为(101.6±1.2)％.以H2 (2.1 mL/min)、He(7.0 mL/min)混合碰撞气消除12C12 C+,12C21H+等干扰的MC-ICP-MS分析方法.分析了40种葡萄酒中镁同位素组成,结果表明:不同产地葡萄酒中镁同位素组成差异明显；而且,来自同一产区不同葡萄园的葡萄酒中镁同位素组成也有显著差异.这表明镁同位素具有区分不同产地葡萄酒的能力,而且地理分辨率较高.对于部分镁同位素组成差异不明显的样品,结合元素分析手段,可以准确区分.
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