GC-MS方法诊断新生儿苯丙酮尿症

用甲醇提取血样中的苯丙氨酸(Phe)、酪氨酸(Tyr)，提取液离心去蛋白质，用正丁醇将其中的苯丙氨酸和酪氨酸丁酯比，再用三氟醋酸酐酰化后进行GC-MS分析，测定Phe，Tyr特征离子峰面积，用外标法计算出Phe和Tyr的摩尔浓度，根据Phe和Tyr摩尔浓度比值来诊断新生儿苯丙酮尿症(PKU)。

GC-MS screening of phenylketonuria in newborns

Phenylalanine(Phe) and Tyrosine(Tyr) were extracted from dry blood spots with 0.1% mol/L HCl-methanol. The proteins in the extraction were revomed by centifuging. Phe and Tyr were treated with 3.0 mol/L HCl-butanol. Phe and Tyr butyl esters were treated with trifluoro acetic anhydride. The derivatives from Phe and Tyr were analyzed by GC-MS. The contents of the two amino acids in blood samples were determined by calculating the areas of their derivatives with reference to an exterior standard. Finally the diagnosis of PKU was made on the basis of the molar content ratios of Phe to Tyr.