Determination of15N isotopic enrichment and concentrations of allantoin and uric acid in urine by gas chromatography/mass spectrometry
作者:X. B. Chen、A. G. Calder、P. Prasitkusol、D. J. Kyle、M. C. N. Jayasuriya
DOI:10.1002/(sici)1096-9888(199802)33:2<130::aid-jms616>3.0.co;2-y
日期:1998.2
A method for the determination of 15N enrichment and concentration of allantoin and uric acid simultaneously in urine using gas chromatography/mass spectrometry (GC/MS) is described. The urine samples contained [1,3-15N2] uric acid and its oxidation product allantoin. The uric acid and allantoin were isolated using an AG1-X8 (Cl-form) anion-exchange column and heated with a mixture containing 1:1 dimethylformamide
描述了一种使用气相色谱/质谱(GC / MS)同时测定尿液中尿囊素和尿酸中15N富集和浓度的方法。尿液样本中含有[1,3-15N2]尿酸及其氧化产物尿囊素。使用AG1-X8(Cl型)阴离子交换柱分离尿酸和尿囊素,并用含有1:1二甲基甲酰胺和N-(叔丁基二甲基甲硅烷基)-N-甲基三氟乙酰胺(MTBSTFA)的混合物加热。将尿囊素和尿酸形成的叔丁基二甲基甲硅烷基(TBDMS)衍生物注入与电子轰击电离条件下运行的质谱仪连接的气相色谱仪中。从尿囊素的m / z 398、399和400和m / z 567和569的尿酸中M-57离子的丰度进行同位素比测量。通过尿酸酶处理由[1,3-15N2]尿酸生产15N2尿囊素(99原子%),并用作标准品。尿囊素和尿酸的定量基于同位素稀释,方法是向尿液样本中加入已知量的99 at。%[15N]尿酸和尿囊素内标。从制备的标准物中观察到的同位素比测量值与理论值相符。同位素比值和浓度测量值的变异系数分别为0