高效液相色谱法测定黄瓜中多菌灵残留量的不确定度评定

Evaluation of the Uncertainty of the Residue of Carbendazim in Cucumber by High Performance Liquid Chromatography

本文建立高效液相色谱法测定黄瓜中多菌灵残留量的不确定度评定方法。黄瓜样本经乙腈提取,硫酸镁盐析和净化,利用反相离子对试剂色谱分离,在275 nm波长处检测多菌灵,保留时间定性,外标法定量,建立该实验过程的数学模型并对不确定度来源进行分析,确定不确定度的主要分量,计算得出合成相对标准不确定度、扩展不确定度。结果表明,当多菌灵残留量为1.98 mg·kg^(-1)时,以正态分布估计,置信概率为95%、包含因子k=2时,其扩展不确定度为0.10 mg·kg^(-1);在实验过程中标准溶液及其配制过程、试样定容过程引入的不确定度对检测结果影响较大。建议相关人员在实验过程中严格按照标准规范进行操作,减少人为误差,确保检测结果的准确性和可靠性。

This paper establishes an uncertainty evaluation method for determining the amount of carbendazim in cucumber.Carbendazim is extracted from cucumber samples using acetonitrile,salted out and purified by magnesium sulfate,separated by reversed-phase ion-pair reagent chromatography,and determined at 275 nm wavelength.The retention time is qualitative and the external standard method is quantitative.The mathematical model of the experimental process is established and the source of uncertainty is analyzed to determine the main component of uncertainty,and the relative synthetic standards uncertainty and expansion uncertainty are calculated.The results show that when the amount of residue of the spirit is 1.98 mg·kg~(-1),it is estimated at a normal distribution.When the probability of confidence is 95%,and the expansion uncertainty is0.10 mg·kg~(-1) when the factor k=2.The uncertainty introduced into the standard solution and its preparation process and the uncertainty introduced into the sample volume determination process have a great influence on the test result.Through the assessment of measurement uncertainty,it is necessary to operate strictly in accordance with the standard specifications to reduce human errors and ensure the accuracy and reliability of the test results.