Schwartz R, Giesecke C C
Clin Chim Acta. 1979 Sep 15;97(1):1-8. doi: 10.1016/0009-8981(79)90018-4.
A method for the detection of 26Mg enrichment of natural Mg was developed based on mass spectrometry (MS) of a Mg chelate made by complexing Mg to 2,2',6,6'-tetramethylheptanedione (THD). The chelate [Mg(THD)2] was extracted at pH greater than 9 from dilute aqueous solutions into ethyl ether, recovered by sublimation at room temperature, and introduced by solid probe into a Finnigan 3300 mass spectrometer. The chelate was ionized by electron impact. Samples were heated to a maximum temperature of 200 degrees C at a rate of 700 degrees C/h. Each analysis required 1--5 micrograms Mg(THD)2. Enrichment levels as low as 5% above natural abundance could be detected satisfactorily. Precision was best at 26Mg enrichment levels of 8--40% above natural abundance, the levels most likely to be encountered in analysis of plasma, urine and fecal samples from experimental subjects who had received 26Mg as a tracer. The method was compared to neutron activation (NA) analysis and judged superior.
基于镁与2,2',6,6'-四甲基庚二酮（THD）络合形成的镁螯合物的质谱分析（MS），开发了一种检测天然镁中26Mg富集的方法。螯合物[Mg(THD)2]在pH大于9的条件下从稀水溶液中萃取到乙醚中，通过室温升华回收，并通过固体探针引入菲尼根3300质谱仪。螯合物通过电子轰击电离。样品以700℃/h的速率加热至最高温度200℃。每次分析需要1 - 5微克Mg(THD)2。可以令人满意地检测到比天然丰度低至5%的富集水平。在比天然丰度高8 - 40%的26Mg富集水平下精度最佳，这是在接受26Mg作为示踪剂的实验对象的血浆、尿液和粪便样本分析中最可能遇到的水平。该方法与中子活化（NA）分析进行了比较，并被判定更优。
