Prenatal diagnosis of organic acidemia by measuring index compounds in dried amniotic fluid on filter paper using GC/MS

应用GC/MS法测定滤纸干羊水中的指标化合物，进行产前诊断丙酸血症或多羧酶缺乏症的研究。即使是偏远地区的医院医生，如果使用该系统，也可以将样品送到我们这里。1.测定系统的建立：1）如何确定滤纸干羊水的取样量是一个关键问题：建立了如下计算方法。仅用AF饱和已知重量的滤纸，并在现场室温下干燥。从滤纸中提取的确认和重现性：将已知量的指标化合物加入AF中，将其吸附到滤纸上并干燥。用蒸馏水从滤纸中提取。采用文献报道的方法制备提取液进行GC/MS分析，并与原样品进行比较.对照值：用滤纸吸收对照羊水测定样本，求出对照值。我们还分析了羊水的滤纸从怀孕的“危险”丙酸学术界，并可以作出明确的诊断，每一个案件。这种方法是一个半定量分析，但它变得明显，这种方法是适用于产前诊断。

Study of prenatal diagnosis of propionic acidemia or multiple carboxylase deficiency by measuring index compounds in dried cell-free amniotic fluid (AF) on filter paper using GC/MS. Even a doctor of a hospital of a remote region can send a sample to us if he uses this system.1.Establish of assay system:1) It was a most key point how to know the sampling volume of AF on a dried filter paper: It was established a calculating method as below. It was only saturated a filter paper known weight with AF and dried up under room temperature on site. It could be calculated the absorbed volume of AF from the weight of paper.2) Confirmation of extraction from filter paper and reproducibility: Known quantity of index compounds was added to AF, and it was absorbed to a filter paper and dried. It was extracted with distilled water from the filter paper. The extractive was prepared for GC/MS analysis by the method of previous report of AF. The measurement data were compared with the data of original AF.2. Control Values:We measured the sample which let a filter paper absorb control amniotic fluid and found control value. We also analyzed the filter paper of the amniotic fluids from pregnancies "at risk" for propionic academia, and could make a clear-cut diagnosis to each cases.This method is a semiquantitative analysis, but it became clear that this method is applicable for prenatal diagnosis.