C-反应蛋白纯品的同位素稀释质谱法测定与国际比对

建立了C-反应蛋白的液相色谱-同位素稀释串联质谱检测方法。作为C-反应蛋白纯品标准物质的潜在定值方法，选取同位素标记亮氨酸和缬氨酸为内标，重量法与待测样品准确混合。利用Zorbax SB-Aq色谱柱分离，电喷雾三重四极杆串联质谱多反应监测模式(MRM)测定。对样品的测定不确定度进行计算与分析，测得结果为（41.5±0.9） mmol/kg。利用该方法参加了基于中、日、韩三国计量院合作框架下的国际比对，并取得了比对结果的等效一致。

Measurement and International Comparison for C-Reactive Protein by Isotope Dilution Mass Spectrometry

The determination of C-reactive protein (CRP) by liquid chromatography-isotope dilution mass spectrometry（LC-IDMS） was developed. As the potential value assay method for CRP pure certified reference material (CRM), the isotope labeled leucine and valine were selected as internal standard added into the CRP samples. The samples were separated by Zorbax SB-Aq column, and measured by tandem mass spectrometer equipped with an electrospray ionization source operated in multiple reaction monitoring (MRM) mode. The determination of uncertainty was calculated and analyzed, the measured results were (41.5±0.9) mmol/kg. International comparison of Japan, South Korea and China was carried out by this method and obtained the equivalent comparison results.