电感耦合等离子体质谱法测定蔬菜中16种稀土元素

Determination of 16 rare earth elements in vegetables by inductively coupled plasma mass spectrometry

目的建立电感耦合等离子体质谱法(ICP-MS)测定蔬菜中16种稀土元素的分析方法。方法采用干式灰化法对蔬菜样品进行前处理,以103Rh、115In、185Re作为内标消除非质谱干扰,碰撞反应池消除质谱干扰,采用电感耦合等离子体质谱仪测定蔬菜中16种稀土元素。使用干式灰化法分别对GBW10015菠菜、GBW10014圆白菜2种国家标准物质进行了前处理,以验证干式灰化法的前处理效果;对测定方法的干扰及其消除进行了探讨;并对该测定方法做了系列可行性试验。结果在0.0μg/L^5.0μg/L时,相关系数均≥0.999 8,方法的检出限为1.6×10-5mg/kg^4.8×10-4mg/kg,回收率为90.1%~110.0%,相对标准偏差为0.83%~5.22%,经过对2种国家标准物质GBW10015菠菜、GBW10014圆白菜的测定,16种稀土元素的测定值均与真值相吻合。结论方法精密准确可靠,可满足蔬菜中稀土元素检测的需要,便于推广。

Objective To establish a method for determination of 16 rare earth elements in vegetables by inductively coupled plasma mass spectrometry（ ICP-MS）. Methods The pretreatment was performed using dry ashing method.103 Rh,115In,and185 Re were used as the internal standards to eliminate non-spectroscopic interference,while collision reaction cell was used to eliminate mass spectroscopic interference. ICP-MS was used to determine 16 rare earth elements in vegetables. To identify the efficiency of dry ashing treatment,two standard reference materials,GBW10015 spinach and GBW10014 cabbage,were selected and pre-treated by dry-ashing method. Furthermore,interference presented in determination and its elimination was discussed. In addition,a series of feasibility tests were conducted. Results At the range of 0. 0 μg / L-5. 0 μg / L,the linear correlative coefficient for all the elements was ≥0. 999 8,the detection limit was 1. 6 × 10^-5mg / kg-4. 8 × 10^-4mg / kg,the recovery rate was at the range of 90. 1%-110. 0%,the RSD was among 0. 83%-5. 22%,and the measured values of 16 rare earth elements were consisted with the true values in two national standard reference materials GBW10015 spinach and GBW10014 cabbage. Conclusion This method has advantages of high sensitivity and precision,and it can meet the requirements of the rare earth elements in vegetables detection,and is easy to promote.