title: Speciation analysis of selenium in rice samples by using capillary electrophoresis-inductively coupled plasma mass spectrometry.
abstract: An enzyme-assisted extraction used to extract all species of selenium in rice sample and a sensitive analytical method for the determination of ultratrace Se(VI), Se(IV), SeCys(2) (selenocystine) and SeMet (selenomethionine) with capillary electrophoresis-inductively coupled plasma mass spectrometry were firstly described in this study. The extraction method is simple, effective and can be used to extract trace selenium compounds in rice with high extraction efficiency and no altering its species. The analytical method has a detection limit of 0.1-0.9 ng Se/mL, and can be used to determine trace Se(VI), Se(IV), SeCys(2) and SeMet in rice directly without any derivatization and pre-concentration. With the help of above methods, we have successfully determined Se(VI), Se(IV), SeCys(2) and SeMet in selenium-enriched rice within 18 min with a recovery of 90-103% and a RSD (relative standard deviation, n=6) of 3-7%. Our results indicated that selenium-enriched rice contained only one species of selenium, SeMet, and its concentration is in range of 0.136-0.143 μg Se/g dried weight. The proposed method providing a realistic approach for the nutritional and toxical evaluation of different selenium compounds in nutritional supplements.
authors.affiliation: Key Laboratory of Analysis and Detection for Food Safety of Ministry of Education, Fujian Provincial Key Lab of Analysis and Detection for Food Safety, Department of Chemistry, Fuzhou University, Fuzhou, Fujian 350108, China.
authors.forename: YunQiang
authors.initials: Y
authors.lastname: Zhao
authors.forename: JinPing
authors.initials: J
authors.lastname: Zheng
authors.forename: MingWei
authors.initials: M
authors.lastname: Yang
authors.forename: GuiDi
authors.initials: G
authors.lastname: Yang
authors.forename: YongNing
authors.initials: Y
authors.lastname: Wu
authors.forename: FengFu
authors.initials: F
authors.lastname: Fu
mesh_terms: D019075:Electrophoresis, Capillary / Q000379:methods*; D013058:Mass Spectrometry / Q000379:methods*; D012275:Oryza / Q000737:chemistry*; D015203:Reproducibility of Results; D012643:Selenium / Q000032:analysis*
chemical_list: D012643:Selenium