ICP-AES测定植株样品中不确定误差的估算

为了探讨植株样品中多种大量、微量元素的测定方法,本文采用湿法硝酸-高氯酸消解,用电感耦合等离子发射光谱法(ICP-AES)同时测定试样中K、Ca、Mg、Cu、Zn、Fe、Mn、Al、Cd、Cr、Mo、P、Pb、S等元素,研究了样品的处理、标准样品的配制等过程不确定误差的问题。结果表明,元素的检出限为0.025-0.064μg/mL,变异系数为0.2%-5.3%,标准样品测定的绝对偏差为1.35%-4.50%(除Pb以外,为-8.33%)。由于测定中变异过大,所以B、Si不宜采用多元素法同时测定。在所有考虑到的不确定误差中,标准样品的制备和消解样品的转移是最重要的两个误差源。ICP-AES法同时测定植株体大量、微量元素是一种简便、快速、准确、精密度好的方法。

Uncertainties Errors Evaluation in the Determine Macro or Minor Elements of Plant Samples by ICP-AES

One method was built up to determine many macro-or minor elements of plant samples,which including digested samples by HNO3-HClO4 and run it on ICP-AES.The disposal of samples,the confection of the standard samples and the disturbance of spectrum were studied.Meanwhile,the uncertainties errors were considered in the whole procedure.The analysis,precision and comparison of standard samples were taken.The results showed that this is a satisfied method for plant samples,which can be used to determine K,Ca,Mg,Cu,Zn,Fe,Mn,Al,Cd,Mo,P,Pb and S but Si and B content in plant samples.Among all uncertainties errors,preparing standard solution and transferring digested solution into ICP tubes were two key processes to be taken cautions.In short,ICP-AES is a simply,rapid,nicely method with high precision in the determination of plant samples.