气相色谱-质谱法用于人尿中4种二羧酸的含量检测

摘要

Objective To establish an analytical method for the determination of organic acids dicarboxylic acid in human urine.Methods The content of dicarboxylic acid in the urine was detected by ion bombardment (EI) ion source mass spectrometry.Urine sample pretreatment:by using internal standard method,the sample was taken α-ketoxime reaction first,and then sulfuric acid methanol solution was carried out the process of methyl esterification,chloroform was used for extraction of organic dicarboxylic acid.Results The content of suberic acid in mitochondrial myopathy group was lower than that in normal group and myasthenia gravis group (P ＜ 0.05).The concentration of pimelic acid in mitochon drial myopathy group and myasthenia gravis group were significantly lower than those in normal group (P ＜ 0.05).The intra-day RSD was 1.00％-2.84％,and the inter-day RSD was 2.01％-3.87％.The average recovery rate of the added standard was 88.47％-104.09％,and RSD was 1.24％-4.19％.Conclusion The method of gas chromatography-mass spectrometry for determination of urinary dicarboxylic acid organic acid compounds is simple,accurate,with good reproducibility,which can be used to help screening carnitine circulating enzyme deficiency inherited metabolic diseases in clinic.%目的 建立测定人尿中有机酸二羧酸类含量分析方法.方法 采用离子轰击(EI)离子源质谱检测尿中二羧酸含量.尿液样品前处理:采用内标法,样品先进行α-酮肟反应,再硫酸甲醇溶液进行甲酯化处理,氯仿萃取有机二羧酸.结果 线粒体肌病组辛二酸含量均低于正常组和重症肌无力组(P＜0.05);线粒体肌病组和重症肌无力组庚二酸含量均明显低于正常组(P＜0.05).精密度日内RSD为1.00％～2.84％,日间RSD为2.01％～3.87％,加标平均回收率为88.47％～104.09％,RSD为1.24％～4.19％.结论 气相色谱质谱法测定尿液二羧酸类有机酸化合物方法简便准确,重现性好,可用于帮助临床筛查肉碱循环酶缺陷遗传代谢病.