地下水中Fe的ICP-MS检测和修正方法

Detection and correction of iron in groundwater by ICP-MS

提出了使用电感耦合等离子体质谱法检测地下水中Fe的过程中,标准系列溶液与样品溶液由于基体不同,随雾化气流量变化时所受到的影响程度不一致,对样品中Fe的分析结果的准确性和可靠性产生不利影响。同时提出在线内标溶液含有一定浓度的Fe,并把相应的检测值带入分析结果,对低含量样品中Fe的分析结果的准确性和可靠性产生不利影响。通过实验研究,说明了使用监控样技术对这两个问题进行修正能够获得良好效果,并且相应说明了监控样的制备方法、保存条件和使用期限及对在线内标溶液的处理方法。在这个基础上,建立了新的电感耦合等离子体质谱法检测地下水中Fe的方法,重新确定了方法参数。方法的检出限(DL)达到18.9ng/mL。方法精密度(RSD)为6.11%～8.56%(n=12)。加标回收率为97.55%。

Using inductively coupled plasma mass spectrometry detection of iron in groundwater, because the standard solution and sample solution matrix is not the same, so when they were affected is not the same as the carrier gas flow rate changes. This issue adversely affect the accuracy and reliability of the determination of iron in the sample results. At the same time raise another issue, online internal standard solution containing a certain concentration of iron, the detection value is added to the iron test results, it can advemely affect the accuracy and reliability of the test results of the iron in the low-concentration samples. Through experimental study, these two issues is an effective solution by using the correction technique of control samples, and the control samples preparation methods, storage conditions and period of use and on-line internal standard solution approach is illustrated. On this basis, the new detection method using inductively coupled plasma mass spectrometry technology of iron in groundwater was established, and the parameters of the method is re-determined. The detection limit of the method for iron are 18.9ng/mL. The method has been applied to the determination of iron in groundwater with precision of 6.11%-8.56% RSD（n=12）.