稀酸加热振荡提取-电感耦合等离子质谱仪测定植物油中痕量硒

Determination of trace selenium in vegetable oil by inductively coupled plasma mass spectrometry with dilute acid heating oscillation extraction

建立了稀酸加热振荡提取-电感耦合等离子体质谱仪测定植物油中的痕量硒方法,优化了提取过程中的温度和稀酸浓度。优化后的条件为:2 g植物加入10%(V/V)硝酸,在80℃加热振荡70 min可将植物油中的蛋白态硒转化为游离态硒并提取完全。方法线性范围为0. 2～40μg/L,方法检出限为0. 2μg/kg,加标回收率在84. 4%～105. 0%之间,相对标准偏差(RSD,n=6)小于5. 0%。该方法与传统的微波消解法测定的结果无显著性差异(P> 0. 05)。

A new sample preparation method was developed to analyze the selenium in vegetable oii by inductive coupled plasma mass.Two gram oil sample was extracted by 10%(V/V)HNO3 at 80℃ water bath heating with mechanical shaking.Protein -Se could be transferred to inorganic Se,and extracted by 10%(V/V)HNO3 in 70 minutes.The linearity ranged from 0.2 to 40μg/L with the limit of detection of 0.2 μg/kg.The recoveries ranged from 84.4% to 105.0% with relative standard deviation less than 5.0% There was no significant difference (P >0.05 )of the results obtained by this method and microwave digestion method,which meant the developed method had good accuracy.