风冷回流消解-电感耦合等离子体质谱法同时测定植物样品中46个元素

摘要

Plant samples were dissolved with HNO3 and H2O2 respectively in grinding conical flask placed directly on an ordinary flat aluminum electrothermal plate with an air-cooled tube. The reflux devices, consisting of 45 conical flasks can be heated simultaneously. This method keeps the sample solution under slight boiling conditions to digest the sample completely rendering the critical digestion time unnecessary. The 46 kinds of element contents in samples were determined simultaneously by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The standard reference materials for the plants (GBW 10012, GBW 10014 and GBW 10019) were analyzed and the results were in good agreement with the certified values. The relative standard deviations ( n = 6 ) ranged from 0.44% to 5. 59% . Compared to the methods of microwave digestion and dry ashing, this method is simple, rapid,uses less reagents and has lower blank and salinity which make it convenient for multi-elements measurements of plant sample by ICP-MS. The operating conditions of the ICP-MS were optimized by using debugging hydraulics, and the interference relationship was studied. The interference of determination was eliminated effectively by using a mathematical model.%采用HNO3-H2O2体系对植物样品进行风冷回流消解,电感耦合等离子体质谱法(ICP-MS)同时测定植物样品中46个元素的含量.将称有样品的磨口锥形瓶加装风冷管后直接放在普通平板铝块电热板上,一次可对45个锥形瓶回流装置同时进行加热,不需要严格地规定消解时间,保证回流加热微沸消解至消解完全即可.植物标准物质(GBW 10012、GBW 10014和GBW 10019)的分析结果与标准值相一致,方法精密度(RSD,n=6)为0.44％～5.59％.与干法灰化消解和微波消解等样品处理方法相比较,操作简单快捷,试剂用量少,空白值较低,溶液盐度较小,有利于植物样品中多元素ICP-MS同时测定.采用调试液调节ICP-MS仪器测定的最佳化,确定了ICP-MS测定的最佳条件,同时探讨了元素之间的干扰关系,采用数学校正法有效地消除了测定的干扰.