食品中硒的含量检测及形态分析

采用GB 5009.93—2017《食品安全国家标准食品中硒的测定》中规定的食品中硒元素含量检测方法对食品中硒元素进行含量检测,所得标准曲线方程为y=2626.595x+126.650,R²=1.000,硒元素在0~100μg/L范围内线性相关系数均为1.000,线性关系良好,并通过样品验证证明该方法准确有效。另外,该试验建立了利用高效液相色谱-电感耦合等离子色谱(HPLC-ICP-MS)联用分离检测富硒食品中硒酸根(SeO₄^2-)、亚硒酸根(SeO₃^2-)、硒代胱氨酸(SeCys₂)、硒甲基硒代半胱氨酸(MeSeCys)、硒代蛋氨酸(SeMet)5种不同硒元素形态的方法。该方法利用胃蛋白酶在0.1%盐酸体系下酶解提取食品中的硒化合物,采用Hamilton PRP X-100阴离子交换柱作为分离柱,以5 mmol/L柠檬酸、氨水调节pH 4.7为流动相,等度洗脱分离5种硒化物,再运用ICP-MS进行检测。结果表明,该方法对于5种硒元素形态分离效果较好,在900 s内可完成5种硒形态的快速准确分析,是一种有效可行的对富硒产品中硒形态的分析方法。

Content Detection and Speciation Analysis of Selenium in Foods

This study uses GB 5009.93—2017"National Food Safety Standard-Determination of Selenium in Foods"to determine the content of selenium in food.The obtained standard curve equation is y=2626.595 x+126.650,R²=1.000,the linear correlation coefficients of selenium in the range of 0-100μg/L are all 1.000,and the linear relationship is good.The method is proved to be accurate and effective by sample verification.In addition,a method for the determination of 5 selenium species(SeO₄^2-,SeO₃^2-,SeCys₂,MeSeCys and and SeMet)in selenium-enriched foods by high performance liquid chromatography-inductively coupled plasma chromatography(HPLC-ICP-MS)has been established.This method uses pepsin to extraction of selenium compounds in food under 0.1%hydrochloric acid system.A Hamilton PRP X-100 anion exchange column is used as the separation column,5 selenium compounds are eluted and separated with 5 mmol/L citric acid and ammonia water to adjust the pH to 4.7,and then detected by ICP-MS.The results show that this method has a good effect on the separation of 5 selenium element forms.The fast and accurate analysis of five selenium forms within 900 s.It is an effective and feasible analysis method for selenium forms in selenium-rich products.