Abstract: 【Objective】 The non-derivatized MS/MS method to measure amino acids was established for the detection and screening of the amino acid disorders. 【Methods】 The measurement of amino acids including Alanine(Ala), Arginine(Arg), Citrulline(Cit), Glycine(Gly), Leucine(Leu), Methionine(Met), Methionine(Met), Ornithine(Orn), Phenylalanine(Phe), Proline(Pro), Tyrosine(Tyr) and Valine(Val)involved extraction of dried blood spots with a solution containing 11 stable-isotope labeled internal standards and analysis using a tandem mass spectrometry(MS/MS) system. The precision, accuracy of the method were analyzed and 1 093 high-risk children were screened by MS/MS. 【Results】 The precisions(CV) of the amino acids with lower concentration were in the area of 5.84%～9.57%(within-run) and 13.89%～18.65%(between-run), respectively. The precisions of the amino acids with higher concentration were in the area of 4.57%～8.78%(within-run) and 13.55%～17.25%(between-run), respectively. The derivation in the assay of amino acids varied from 4.24% to 16.16%, the average was 4.10%. 11 patients were positive including four with hyperphenylalaninemia, three with Maple Syrup Urine Disease, two with Citrullinemia, one with tyrosinemia and one with Arginemia. 【Conclusion】 The high precision and accuracy of the non-derivatized MS/MS method provides the values in the clinical application.

Key words: amino acid, tandem mass spectrometry, non-derivatized

摘要： 【目的】 应用非衍生化串联质谱技术检测多种氨基酸,以便用于氨基酸代谢障碍的检测和筛查。 【方法】 使用含11种稳定同位素标记的氨基酸内标准品的溶剂萃取滤纸干血片中的氨基酸,直接进样串联质谱仪,检测丙氨酸(Ala),精氨酸(Arg),瓜氨酸(Cit),谷氨酸(Gly),亮氨酸(Leu),蛋氨酸(Met),鸟氨酸(Orn),苯丙氨酸(Phe),脯氨酸(Pro),酪氨酸(Tyr),缬氨酸(Val)的浓度。分析该方法的精确性和准确性;并应用于1 093例高危儿童的筛查和诊断。 【结果】 低水平浓度氨基酸的批内CV为5.84%～9.57%,批间CV为13.89%～18.65%;高水平浓度酰基肉碱的批内CV为4.57%～8.78%,批间CV为13.55%～17.25%;测定值与靶值的偏倚为4.24%～16.16%,平均相对偏倚为4.10%;检出5种共11例氨基酸代谢障碍,包括高苯丙氨酸血症4例,枫糖浆尿症 3例,瓜氨酸血症 2例、酪氨酸血症及精氨酸血症各1例。 【结论】 非衍生化串联质谱检测氨基酸有较高的精确性和准确度,有临床应用价值。

关键词: 氨基酸, 串联质谱, 非衍生化