Palmer I S, Thiex N
South Dakota State University, Department of Chemistry and Biochemistry, Brookings 57007, USA.
J AOAC Int. 1997 May-Jun;80(3):469-80.
A total of 17 laboratories participated in a collaborative study for the determination of selenium in feeds and premixes using either a fluorometric or a continuous hydride generation atomic absorption (HGAA) method. Each collaborator analyzed 16 blind duplicate samples of feed and premixes from various feed manufacturers. The amount of Se in these materials ranged from 0.2 to 5500 micrograms/g. Six laboratories used only the fluorometric procedure, 8 laboratories used only the hydride generation atomic absorption procedure, and 3 laboratories used both procedures. One laboratory in the fluorometric study and 3 laboratories in the HGAA study were initially excluded because of invalid data. Poor agreement between the blind duplicates indicated probable sample interchange and/or dilution error. The data from 8 laboratories were submitted to statistical analysis, including data from 2 laboratories participating in both studies. The repeatability standard deviation (RSDr) for samples analyzed by the fluorometric procedure ranged from 5.9 to 33%, and the reproducibility standard deviation (RSDR) ranged from 12 to 33%. RSDr for samples analyzed by HGAA ranged from 2.8 to 18%, and RSDR ranged from 4.0 to 36%. Both fluorometric and continuous hydride generation atomic absorption methods for the determination of Se in feeds and premixes have been adopted first action by AOAC INTERNATIONAL.
共有17个实验室参与了一项协作研究，该研究采用荧光法或连续氢化物发生原子吸收（HGAA）法测定饲料和预混料中的硒。每位协作人员分析了来自不同饲料生产商的16个饲料和预混料的重复盲样。这些材料中硒的含量范围为0.2至5500微克/克。6个实验室仅使用荧光法，8个实验室仅使用氢化物发生原子吸收法，3个实验室同时使用这两种方法。荧光法研究中的1个实验室和HGAA研究中的3个实验室因数据无效而最初被排除。重复盲样之间的一致性较差表明可能存在样品交换和/或稀释误差。来自8个实验室的数据被提交进行统计分析，其中包括参与两项研究的2个实验室的数据。荧光法分析样品的重复性标准偏差（RSDr）范围为5.9%至33%，再现性标准偏差（RSDR）范围为12%至33%。HGAA分析样品的RSDr范围为2.8%至18%，RSDR范围为4.0%至36%。用于测定饲料和预混料中硒的荧光法和连续氢化物发生原子吸收法均已被AOAC INTERNATIONAL首次采用。
