时间分辨荧光免疫层析法检测大米中黄曲霉毒素B_1的不确定度分析

Uncertainty analysis for detecting aflatoxin B_1 in rice by time-resolved fluorescence immunochromatographic

对采用时间分辨荧光免疫层析法(TRFIA)测定大米中黄曲霉毒素B1(AFB1)含量的不确定度进行分析,找出影响不确定度的主要分量。根据CNAS GL06—2006《化学分析中不确定度的评估指南》中提供的方法,建立数学模型,分析测定过程中各不确定度分量的来源,并对其进行量化和评定。结果表明,相对标准合成不确定度为3.703%、相对标准总不确定度为7.406%,大米中黄曲霉毒素B_1含量为(5.235 2±0.387 7)μg/kg(k=2)。不确定度主要来源于标准曲线拟合、重复性检测和样品提取,分别占比20.82%、23.27%和19.35%。测定过程中,应首先制备准确且稳定的标准曲线,并增加平行样的测定次数,提高提取操作的准确度。本文所建立的不确定度评定方法可用于TRFIA法测定大米中黄曲霉毒素B_1含量结果的评定。

The uncertainty for detecting aflatoxin B1(AFB1)in rice by the time-resolved fluorescence immunochromatographic assay(TRFIA)was analyzed,and the main components that affect the uncertainty were found out.Based on the instruction in CNAS?GL06:2006 Guidance on Evaluating the Uncertainty in Chemical Analysis,a mathematical model was established,the source of uncertainty component was analyzed,the quantity of uncertainty component was calculated and evaluated.The results showed that the relative standard synthetic uncertainty was 3.703%,the relative standard total uncertainty was 7.406%,and the AFB1 content in rice was(5.235 2±0.387 7)μg/kg(k=2).The uncertainty mainly come from the standard curve fitting,repeatability determination and sample extraction,accounting for 20.82%,23.27%and 19.35%,respectively.In the determination process,an accurate and stable standard curve must be firstly prepared,the determination times of parallel samples should be increased,and the accuracy of extraction should be raised.The uncertainty evaluation method established in this paper could be used for judging the determination results of AFB1 in rice by TRFIA.