ICP-MS法同时测定进口饮料中21种无机元素

Simultaneous Determination of 21 Inorganic Elements in Imported Drinks by Inductively Coupled Plasma Mass Spectrometry

建立电感耦合等离子体质谱(ICP-MS)同时测定进口饮品中镁、铝、钾、钙、钛、钒、铬、锰、铁、镍、铜、锌、砷、硒、镉、锡、锑、铽、汞、铅和铋共21种无机元素的分析方法。样品在硝酸过氧化氢体系中经微波消解后直接上样分析,采用氦气碰撞模式消除了多原子离子质谱干扰,以钪、锗、铑、铟、铱作为内标元素校正了质谱分析中基体效应并补偿了信号漂移。结果表明,该方法加标回收率(n=6)在84.6%~106.6%之间,选择国家一级标准物质豆角(GBW10021)、胡萝卜(GBW10047)和芹菜(GBW10048)验证方法的可靠性,待测元素测定结果均在标准值允许范围内,日间相对标准偏差(n=6)在1.1%~16.2%之间。试验对6种进口韩国饮料中上述21种元素进行了测定,铅、镉、砷、锡等有害元素含量均低于国家标准。该法适合于饮料中多种元素的同时测定。

An analytical method based on inductively coupled plasma mass spectrometry （ICP-MS） has been developed for the simultaneous determination of 21 inorganic elements （Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd, Sn, Sb, Tb, Hg, Pb and Bi） in imported drinks. After the samples were pretreated by microwave digestion under HNO3-H2O2, octopole collision-reaction system （ORS） was used to eliminate the polyatomic interferences. Sc, Ge, Rh, In and Ir were used as internal standard elements to compensate matrix effect and signal drift. The results showed that the recoveries for spiked samples were in the range of 84.6%-106.6%. The established method was validated by analyzing the National Standard Reference Material of Beans （GBW10021） , carrot（GBW10047） and Celery（GBW10048） which obtained the relative standard deviation values of reproducibility （n=6） were 1.1%-16.2%, and the analysis results were all in material reference range. Above 21 elements contents in 6 kinds of Korean drinks were determined, Pb, Cd, As, Sn were lower than relevant limit requirements. The method of ICP-MS, with the merits of high sensitivity and precision, is suitable for the measurement of inorganic elements contents in drinks.