(1.谱尼测试集团股份有限公司, 北京 100095;2.谱尼测试集团北京科学技术研究院有限公司, 北京 100095)
( 1.Pony Testing International Group Co Ltd, Beijing 100095, China;2.Pony Testing International Group Beijing Science and Technology Research Institute, Beijing 100095, China)
A high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry (HPLC-HG-AFS) for determination of selenium speciations (Se(VI), SeCys2, SeMeCys and SeMet) in Se-enriched foods (Se-enriched protein powder, Se-enriched rice, Se-enriched shiitake mushrooms and Se-enriched yeast, etc.) was developed in this study. Samples were extracted with Tris buffer and hydrolyzed by protease and trypsin, followed by separating on Hamilton PRP-X100 anion exchange column with a mobile phase consisting with V (20mmol/L diamine hydrogen phosphate aqueous solution,pH=6.0)∶V (methanol)=98∶2. Four speciations of selenium were completely separated as achieving the linearity larger than 0.999, the method detection limit reached 25-50μg/kg, and the average recovery rate was 81.37%-93.80% (RSD 2.80%-7.22%). This method was used to detect 4 kinds of selenium morphological compounds in 4 kinds of commercially available selenium-rich foods (Se-enriched protein powder, Se-enriched rice, Se-enriched shiitake mushrooms and Se-enriched yeast). The advantages of this method were simple pretreatment procedure, rapid determination, high accuracy and sensitivity, which provided a method and basis for the evaluation and quality control of selenium in food.