Establishment of a candidate reference method for plasma normetanephrine and its application in the external quality assessment program
10.3760/cma.j.cn114452-20210129-00080
- VernacularTitle:血浆甲氧基去甲肾上腺素候选参考方法的建立及其在室间质量评价计划中的应用
- Author:
Qingxiang LIU
1
;
Weiyan ZHOU
;
Yuhang DENG
;
Zhenni LIU
;
Chuanbao ZHANG
Author Information
1. 北京医院 国家老年医学中心 中国医学科学院老年医学研究院 国家卫生健康委临床检验中心 北京市临床检验工程技术研究中心 中国医学科学院北京协和医学院，北京 100730
- Keywords:
Isotope dilution liquid chromatography tandem mass spectrometry;
Normetanephrine;
External quality assessment
- From:
Chinese Journal of Laboratory Medicine
2021;44(8):736-742
- CountryChina
- Language:Chinese
-
Abstract:
Objectives:To establish a candidate reference method of isotope dilution liquid chromatography tandem mass spectrometry (ID-LC/MS/MS) for the determination of human plasma normetanephrine, and to evaluate the performance of the method. The method was used to quantify the samples of the external quality assessment program, and to initially evaluate the detection status of plasma normetanephrine.Methods:The isotope standard solution of normetanephrine was selected as the internal standard, the gravimetric method was used for sampling, and the standard curve method was used for quantification. Protein precipitation combined with weak cation solid phase extraction was used for pretreatment, and ultra-high liquid chromatography-coupled triple quadrupole mass spectrometry was used for LC/MS analysis. According to the relevant EP documents, the specificity, matrix effect, detection limit, quantification limit, precision, accuracy, and uncertainty of the method were estimated. This method is used to quantify the samples of the 2020 National Center for Clinical Laboratories external quality assessment program of normetanephrine. Taking the average value of this method as the target value, the optimal allowable total error standard of biological variation as the evaluation limit, the quality of the laboratory testing was evaluated.Results:The method had good specificity, and the interferences and matrix effects did not affect the detection results. The detection limit and quantification limit of plasma normetanephrine were 1.08 pg/g and 3.54 pg/g, respectively. The intra-batch coefficient of variation ( CV) and total CV were 0.43%-1.10% and 0.61%-1.42%, respectively. The relative recovery rates were 98.5%～101.9%. The relative expansion uncertainty of the four plasma samples were 3.10%, 2.34%, 2.16%, and 1.73%, respectively. The results of the external quality assessment program showed that the pass rates of the 202013 and 202014 samples were 80% and 85%, respectively. Conclusions:The study established a candidate reference method of ID-LC/MS/MS for the measurement of plasma normetanephrine. The method is accurate, precise and simple, and is expected to be used as a reference method for the determination of plasma normetanephrine, and can be applied to quantify the samples of the external quality assessment program.
