咖啡中14种无机元素的快速质谱分析

Study on the Determination of 14 Inorganic Elements in Coffee by Inductively Coupled Plasma Mass Spectrometry

采用微波消解处理咖啡样品,建立了电感耦合等离子体质谱(ICP-MS)法测定其中Na,Mg,P,Ca,Cr,Mn,Fe,Co,Cu,Zn,As,Se,Mo,Pb等14种无机元素的分析方法。样品采用HNO3+H2O2混合酸微波辅助消解,优化了仪器的工作参数。加标回收率测定结果表明,所有待测元素的相对标准偏差(RSD)均小于3.84%,回收率在92.00%～106.52%之间。该法准确度高,精密好,并能同时进行多种元素测定,完全能满足样品测定要求,可为咖啡中无机元素的快速检测提供科学依据。

Samples of coffee were digested by microwave digestion, and inorganic elements amounts of Na, Mg, P, Ca, Cr, Mn, Fe, Co, Cu, Zn, As, Se, Mo and Pb in sample solutions were determined by inductively coupled plasma mass spectrometry （ICP-MS）. HNO3 ＋H2Oz was used to achieve the complete decomposition of the organic matrix in a closed-vessel microwave oven. The working parameters of the instrument were optimized. The results showed that the relative standard deviation （RSD） was less than 3.84% for all the elements, and the recovery was found to be 92.00--106. 52% by adding standard recovery experiment. This method was simple, sensitive and precise and can perform simultaneous multi-elements determination of coffee, which could satisfy the sample examination request and provide scientific rationale for determining inorganic elements of coffee.