豆类食品中有害重金属元素含量的快速质谱分析

Determination of Heavy Metal Elements in Legume Food Using Rapid Mass Spectrometry Method

[目的]建立可同时测定豆类食品中几种有害重金属元素的分析方法。[方法]利用硝酸-过氧化氢体系高压消解豆类样品,建立了电感耦合等离子体质谱法（ICP-MS）同时测定豆类中Pb、Cd、Tl、As、Cr、Ni 6种重金属元素的分析方法。应用碰撞反应池技术（动能甄别）消除多原子离子等质谱干扰,以Ge、In、Bi和Sc为内标元素校正质谱分析中的基体效应。[结果]在最佳的试验条件下,各元素的检出限在0.11-18.40μg/kg,相关系数均大于0.999。方法应用于国家有证标准物质（GBW10013）测定,测定值均在参考值范围内。[结论]该研究建立的方法灵敏度高、检出限低、准确度高,且操作简单快速,可应用于豆类食品中重金属元素的批量分析。

[Objective] The aim was to establish analysis method for simultaneously determining several harmful heavy metal elements in legume food.[Method] A novel method has been developed for the determination of trace elements,including Pb,Cd,Tl,As,Cr and Ni in legume food by inductively coupled plasma mass spectrometry（ ICP-MS）. Samples were dissolved in a mixture of HNO3 and H2O2in sealed vessels by using a oven. The use of octopole reaction system（ Kinetic energy discrimination） eliminated the interference of polyatomic ions dramatically,Ge,In,Bi and Sc were selected as the internal standard element to overcome non-spectroscopic interference.[Result]Under the optimal conditions,the detection limits were in the range of 0. 11- 18. 40 μg / kg with elemental correlation coefficients over 0. 999. The method was tested using national standard substance（ GBW10013） and the resultswere in good agreement with the recommended values. [Conclusion] The method has the advantages of high sensitive,low detection limit,high accuracy,simplicity and rapidness,and can be used for batch analysis of legume food.