测试ID: METAF
后肾上腺素，24小时分馏，尿液

采用反相液相色谱-串联质谱(LC-MS/MS)稳定同位素稀释法测定尿中肾上腺素。尿中后肾上腺素主要以共轭形式存在。尿液标本在沸水浴中酸化和水解20分钟后，利用提取盒从标本中提取甲肾上腺素和去甲肾上腺素。用20%甲醇(MeOH)从墨盒中洗脱甲肾上腺素和去甲肾上腺素，采用多反应监测阳性模式的LC-MS/MS分析。在水解前加入氘去甲肾上腺素(d3-去甲肾上腺素，200 ng)和氘去甲肾上腺素(d3-去甲肾上腺素，500 ng)作为内标。以下离子对用于分析:甲肾上腺素，(180/148);normetanephrine (166/134);d3-metanephrine (183/151);d3-normetanephrine(169/137)。甲肾上腺素和去甲肾上腺素的浓度是通过LC-MS/MS的峰面积与氘标记的内部标准物的比率来定量的。 A calibration curve, generated from 20% MeOH spiked standards, is included with each batch of patient specimens.(Taylor RL, Singh RJ: Validation of liquid chromatography-tandem mass spectometry method for analysis of urinary conjugated metanephrine and normetanephrine for screening of pheochromocytoma. Clin Chem 2002;48:533-539; Roden M, Raffesberg W, Raber W, et al: Quantification of unconjugated metanephrine in human plasma without interference by acetaminophen. Clin Chem 2001;47:1061-1067)

星期一到星期五