微晶二苯甲酮富集分光光度法测定水中无机硒形态和食品中总硒

A new method for the determination of inorganic selenium speciation in water and total selenium in food by enrichment with microcrystalline benzophenone

建立了微晶二苯甲酮富集分光光度法测定水中无机硒形态和食品中总硒的新方法。Se(Ⅳ)和3,3’-二氨基联苯胺(DAB)反应生成的苤硒脑络合物能被二苯甲酮微晶吸附富集,微晶用乙醇复溶后在430 nm处测定,试样经氢溴酸将Se(Ⅵ)还原成Se(Ⅳ)后可测定总硒并计算Se(Ⅵ)的含量。最佳实验条件下,方法的线性范围为1.0~120μg/L,r=0.9995,检出限0.18μg/L。水样中无机Se(Ⅳ)和Se(Ⅵ)的回收率在96.6%~99.0%之间,食品中总硒的回收率在97.0%~102.5%之间。

A sensitive spectrophotometric method for the determination of inorganic selenium speciation in water and total selenium in food by enrichment and separation with microcrystalline benzophenone has been developed. Se （Ⅳ ） reacted with 3,3 ＇-diaminobenzidine to form a piazselenol complex, which was enriched and separated with microcrystalline benzophenone. The microcrystalline containing the target analyte was redissolved by ethanol and then analyzed at 430 nm. Total selenium content was determined by oxidation of Se （Ⅵ ） into Se （ Ⅳ ） with hydrobromic acid. The linear range and detection limit of this method are 1.0 × 120 μg/L and 0. 18 ixg/L for Se（ Ⅳ）, respectively. The recovery was 96.6% - 99.0% for inorganic selenium species in water and 97.0% ~ 102.5% for total determination in food.