摘要
目的建立一种基于同位素稀释／气相色谱／质谱技术（isotope dilution／gas chromatography／mass spectrometry，ID／GC／MS）的血清尿素候选参考方法。方法以[^13C，^15N2]尿素为内标，用无水乙醇沉淀、去除血清中的蛋白类物质，依次使用丙二醛-二甲基缩醛和N-甲基-（三甲基硅烷基）．三氟乙酰胺（MSTFA）将尿素衍生成为三甲基硅烷氧基嘧啶，用气相色谱／质谱（GC／MS）分析衍生产物，以包括法定量。结果血清尿素测定的批内、批间和总变异系数的平均值分别为0．38％（范围0．12％-0．47％）、0．62％（范围0．49％-0．87％）和0．73％（范围0．51％-0．93％），回收率范围为99．37％-100．95％，分析美国国家标准和技术研究院（NIST）2个水平的血清标准物质SRM909b，测定结果与靶值的偏差小于0．2％。结论建立了ID／GC／MS技术测定血清尿素的方法，方法准确、精密、简便，可望作为血清尿素测定的参考方法。
Objective To develop a candidate reference method for the measurement of urea in human serum based on isotope dilution/gas chromatography/mass spectrometry. Methods [^13C,^15N2] Urea used as internal standard was added to the serum sample and equilibrated with endogenous nonlabeled urea. The serum samples were treated with anhydrous ethanol to remove proteins by precipitation. The serum urea and labeled urea were converted into a trimethylsilyl derivative of 2-hydroxypyrimidine and analyzed by gas chromatography/mass spectrometry system with selected ion monitoring. The concentration of serum urea was calculated by the theory of bracketing method. Results The average value of within-run coefficient of variation （CV） , between-run CV and total CV of the procedure were 0. 38% （ ranged from 0. 12% to 0.47%）, 0.62% （ranged form 0.49% to 0.87%） and 0.73% （ranged from 0.51% to 0.93%）, respectively. The analytical recoveries ranged from 99. 37% to 100. 95% . The results of analyzing the certified reference material SRM909b （ Level Ⅰ and Ⅱ ） showed a bias less than 0. 2%. Conclusion The procedure for measuring urea in serum is a highly accurate and precise method and can be used as a candidate reference method for serum urea assays.
出处
《中华检验医学杂志》
CAS
CSCD
北大核心
2008年第5期536-539,共4页
Chinese Journal of Laboratory Medicine
基金
国家科技支撑计划资助项目（2007BA105809）
国家高技术研究发展计划（863）资助项目（2006AA020909）
关键词
尿素
色谱法
气相
光谱分析
质量
Urea
Chromatography, gas
Spectrum analysis, mass
