Top-down技术控制图法评估电感耦合等离子体质谱法测定大米中镉含量的不确定度

Evaluation of uncertainty in determination of cadmium in rice by inductively coupled plasma mass spectrometry using top-down control chart

中文关键词:  Top-down技术  电感耦合等离子体质谱法  大米  镉含量  不确定度

英文关键词:Top-down technology  inductively coupled plasma mass spectrometry  rice  cadmium content  uncertainty

中文摘要:

      目的 采用Top-down技术控制图法评估电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry, ICP-MS)测定大米中镉含量的不确定度。方法 按照GB 5009.268—2016《食品安全国家标准 食品中多元素的测定》规定的分析方法, 测定大米质控样中镉(Cd)的含量, 采用Top-down技术原理对半年所得30组数据进行分析和评估。结果 通过测量系统的性能检验可得出正态性的检验(As2*)和独立性检验(A2*MR)均＜1, 表明99%概率下测量系统正态独立, 计算得到的扩展不确定度结果为U=0.52 μg/kg。结论 Top-down技术可用于食品检验中对食用农产品检测结果不确定度的评估, 该技术在建立数学模型上更简单, 对测量不确定度结果的评价更灵活、方便。

英文摘要:

      Objective To evaluate the uncertainty of determination of cadmium content in rice by inductively coupled plasma mass spectrometry (ICP-MS) using top-down technique control chart method. Methods According to the analysis method specified in GB 5009.268—2016 National food safety standard-Determination of multi elements in food, the cadmium (CD) content in quality control samples of rice was determined. The 30 groups of data obtained in half a year were analyzed and evaluated by Top-down technology principle. Results The results of the performance test of the measurement system could be obtained that the test of normality (As2*) and independence test (A2*MR) were less than 1, which showed that the normal state of the measurement system was independent under 99% probability. The result of the expanded uncertainty was U=0.52 μg/kg. Conclusion Top-down technology can be used to evaluate the uncertainty of the detection results of edible agricultural products in food inspection. The technology is simpler in establishing mathematical model and more flexible and convenient for the evaluation of the uncertainty results.