电感耦合等离子体质谱法快速测定胶囊中铬的含量

目的采用动态反应池-电感耦合等离子体质谱技术,建立快速测定胶囊中铬的分析方法。方法预消化-微波消解处理胶囊样品,采用动态反应池模式消除干扰,选择反应气NH3,流速为0.6ml/min,Rpq为0.55,将可能干扰铬测定的40Ar12C+、37Cl16O+等离子强度值降低了大约2个数量级。结果铬元素测定标准曲线的线性相关系数为0.9996,以称样量0.5g计,方法检出限为0.03mg/kg,样品加标回收率为86.5%～107.8%,相对标准偏差<5%。结论该方法精密度好、准确性好,适用于胶囊中铬含量的快速、准确测定。

Determination of chromium in capsule by inductively coupled plasma-mass spectrometry

Objective To establish the method which determined the content of chromium(Cr) in capsule by inductively coupled plasma-mass spectrometry.Methods Pre-digestion-microwave digestion procedures were applied to extract Cr from the capsules.The potentially interfering 40Ar12C+ and 37Cl16O+ at the chromium masses m/z 52 and 53 were reduced in intensity by approximately 2 orders of magnitude by using 0.6 ml/min NH3 as reactive cell gas in the dynamic reaction cell(DRC) while a Rpq value of 0.55 was used.Results The correlation coefficient(r) of standard curve was 0.9996,and the detection limit of the method was 0.03mg/kg,and the average recoveries for all determinations ranged from 86.5% to 107.8% with the related standard deviation below 5%.Conclusion The method,which is of good precision and accuracy,is applicable to rapid and accurate determination of chromium content in capsule.