Miller D D, Van Campen D
Am J Clin Nutr. 1979 Nov;32(11):2354-61. doi: 10.1093/ajcn/32.11.2354.
Methodology for use of stable isotopes of iron (54Fe, 57Fe, and 58Fe) as biological tracers was developed. Tracers were quantitated by measurement of ion abundances with a quadrupole mass spectrometer. The volatility of the iron was enhanced by chelation with 2,4-pentanedione prior to analysis. Samples were introduced into the mass spectrometer via a direct inlet probe. Ion abundance ratios were calculated from integrated ion current measurements obtained for selected ions in the two-ligand fragment of the chelate. Stable isotope tracer concentrations were calculated from these ratios. A prodecure was developed for the formation and purification of serum iron chelates. The method was used to analyze iron standards and blood serum samples containing known amounts of added 58Fe. The disappearance from pony serum of injected 58Fe was used as an in vivo test of the method. It was estimated that a minimum of 1.5 mg of either 54Fe, 57Fe, or 58Fe would be required to label 1 g of natural iron at detectable levels. The methods has promise as an alternative to radioisotope tracer techniques for some applications involving human subjects.
铁的稳定同位素（54Fe、57Fe和58Fe）作为生物示踪剂的使用方法已经开发出来。示踪剂通过用四极质谱仪测量离子丰度进行定量。在分析之前，通过与2,4-戊二酮螯合来提高铁的挥发性。样品通过直接进样探头引入质谱仪。离子丰度比由螯合物双配体片段中选定离子的积分离子电流测量值计算得出。稳定同位素示踪剂浓度根据这些比率计算得出。开发了一种血清铁螯合物形成和纯化的程序。该方法用于分析铁标准品和含有已知添加量58Fe的血清样品。注射的58Fe在马血清中的消失用作该方法的体内试验。据估计，要以可检测水平标记1 g天然铁，至少需要1.5 mg的54Fe、57Fe或58Fe。该方法有望在涉及人类受试者的一些应用中替代放射性同位素示踪技术。
