首页 | 本学科首页   官方微博 | 高级检索  
     


Determination of selenium in human milk by electrothermal atomic absorption spectrometry and chemical modification
Authors:Stavroula Theodorolea
Affiliation:Laboratory of Analytical Chemistry, Chemistry Department, University of Athens, Panepistimiopolis 15771, Athens, Greece
Abstract:A method was developed for the determination of selenium in human milk using electrothermal atomic absorption spectrometry. The use of chemical modifiers as well as their implications during the pyrolysis step was examined. The chemical modifiers that were studied were Zr, Ir as well as the mixed modifier Zr-Ir. The Ir modifier stabilized selenium at 1000 °C, Zr at 800 °C, while the mixed modifier at 1200 °C. The effect of modifier mass was studied and was found that better results are achieved with addition of 2 μg Zr and 2 μg Ir. The characteristic masses of selenium in the presence of Zr, Ir and the mixed modifier were found to be 73.3, 18.0 and 14.7 pg, respectively, while the corresponding limits of detection were found 2.0, 0.50 and 0.41 μg l−1. Consequently better results were obtained with the mixed modifier. The developed method was applied for the determination of selenium in human milk, which was digested with a HNO3 + H2O2 mixture in a microwave oven. The limit of detection of the method was 1.37 μg l−1, the characteristic mass, m0, was 48.8 pg and the repeatability was less than 5% as R.S.D.(%). Matrix matched calibration was used. Recoveries were estimated to be 93-105%. The method was applied to breast milk of Greek women (n = 9) and the Se content was found to be in the range 16.7-42.6 μg l−1 with mean value 27.4 ± 5.5 μg l−1.
Keywords:Selenium   Human milk   Iridium   Zirconium   Chemical modifiers   ETAAS
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号