DETERMINATION OF SERUM URIC-ACID BY ISOTOPE-DILUTION MASS-SPECTROMETRY AS A NEW CANDIDATE DEFINITIVE METHOD
DETERMINATION OF SERUM URIC-ACID BY ISOTOPE-DILUTION MASS-SPECTROMETRY AS A NEW CANDIDATE DEFINITIVE METHOD
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DOI：
10.1021/ac00219a004
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发表时间：
1990-10-15
影响因子：
7.4
通讯作者：
WHITE, E
中科院分区：
文献类型：
--
作者：
ELLERBE, P;COHEN, A;WHITE, E
介绍了一种新的同位素稀释质谱法测定尿酸。将已知重量的[1,3- 15n2]尿酸加入到已知重量的血清中，并使混合物平衡。血清通过阴离子交换树脂，分离尿酸转化为尿酸的四基（叔丁基二甲基硅基）衍生物。为了进行测量，将衍生物注入气相色谱仪与低分辨率磁扇形质谱仪相连接。同位素放射性测量是由m/z 567和569处[m -叔丁基]+离子的丰度进行的。通过在不同色谱条件和不同电离技术下测量同一样品中的尿酸水平，研究了偏差。如果这些验证性测量与主要测量一致，我们就有强有力的证据证明没有测量偏倚。用该方法测定了3个冻干人血清池的尿酸。标准品（SRM） 909制备了4组样品，每组6个样品。候选物SRM 909a由两个尿酸池组成，每个池含有不同水平的尿酸，每个池制备6组样品，每组2份。单次测量的变异系数为0.34% ~ 0.42%，平均值的相对标准误差为0.08% ~ 0.14%。验证性测量的结果表明，在测量中没有显著的偏差。结合高精度和无显著偏差的结果，该方法有资格作为国家临床实验室标准委员会定义的候选确定方法。
A new isotope dilution mass spectrometric method for uric acid is described. A known weight of [1,3-15N2]uric acid is added to a known weight of serum, and the mixture is allowed to equilibrate. The serum is put through an anion-exchange resin, and the isolated uric acid is converted to the tetrakis-(tert-butyldimethylsilyl) derivative of uric acid. For measurement, the derivative is injected into a gas chromatograph interfaced with a low-resolution, magnetic sector mass spectrometer. Isotope radio measurements are made from the abundances of the [M-tert-butyl]+ ions at m/z 567 and 569. Bias is investigated by measuring the uric acid level in the same samples under different chromatograhic conditions and with different ionization techniques. If these confirmatory mesurements agree with the principal measurements, we have strong evidence for the absence of measurement bias. Uric acid was determined in three lyophilized human serum pools by this method. For Standard Reference Material (SRM) 909, four sets of six samles each were prepared. For Candidate SRM 909a, which consisted of two pools, each with a different level of uric acid, six sets of two samles of each level were prepared. The coefficient of variation for a single measurement ranged from 0.34% to 0.42%, while the relative standard error of the mean ranged from 0.08% to 0.14%. The results from the confirmatory measurements demonstrated that there was no significant bias in the measurements. The combination of high precision and absence of significant bias in the results qualifies this method as a candidate definite method as defined by the National Committee for Clinical Laboratory Standards.