摘要
目的应用四极杆型电感耦合等离子体质谱仪(ICP-MS)配合最新的八极杆碰撞/反应池(ORS)消干扰技术进行Fe的同位素比测定研究。方法于现场进行人体代谢试验,受试者口服57Fe稳定性同位素示踪剂,以卡红为标志,粪便监测法收集试验期内的所有粪样,测定粪样中57Fe/56Fe的比值。结果运用ICP-MS的ORS技术可消除由Ar等离子体本身以及样品中存在的Ca等产生的多原子离子对Fe带来的干扰;稀释实际样品到一定范围,基体干扰可忽略不计;标准样品和实际样品短期及长期精密度均小于0.3%;测定两组受试者粪样中的57Fe/56Fe的比值,发现代谢后排泄出的57Fe遵循一定的变化趋势,从而可以测定人体对Fe的代谢吸收比率。结论该技术可准确测定粪样中57Fe/56Fe的比值,可以用来计算评价膳食中铁吸收率的情况,追踪铁在人体中的代谢过程。
Objective The study was aimed to evaluate the application of the quadrupole inductively coupled plasma mass spectrometer （ICP-MS） with collision/reaction cell oetopole reaction system （ORS） to determine the iron stable isotope ratio in human fecal samples. Methods In a field trial on human metabolism, 3. 0mg per subject of iron with ^57Fe enriched was orally administrated, and feces were collected by fecal monitoring. The isotope ratio of ^57Fe to ^56Fe in the prepared fecal sample was detected with the ORS-ICP-MS. Results With the application of ORS-ICP-MS, interferences from the Ar plasma and the calcium-contained polyatomic ions could be eliminated. When the sample solution properly diluted, interferences from the matrix were too little to be noted. The relative stand deviation （ RSD ） of the long-tern and short-term precision was 〈 0.3%. From the changes of ^57Fe/^56Fe in the daily samples, a regularity of fecal iron outputs was presented, and the fractional iron absorption could be evaluated. Conclusion The ratio of ^57Fe to ^56Fe in the fecal sample could be accurately determined by the quadrupole ICP-MS with ORS, based on which the dietary iron absorption could be evaluated and the metabolism of iron in the human body could also be traced.
出处
《卫生研究》
CAS
CSCD
北大核心
2005年第5期603-606,共4页
Journal of Hygiene Research
基金
深圳市科技计划项目(No.200304162)
