电感耦合等离子体质谱(ICP-MS)法测定七类食品中铀钍的含量

Determination of uranium and thorium in the seven categories of food by inductively coupled plasma mass spectrometry( ICP-MS)

采用电感耦合等离子体质谱(ICP-MS)对七类食品(面粉、红薯、香蕉、青菜、猪肉、墨鱼、奶粉)中痕量Th和U进行了测定。选择了最佳仪器测定参数,并选用铋(Bi)为内标元素补偿基体效应和仪器灵敏度漂移。用硝酸消解样品,ICP-MS可直接测定食品中Th和U,回收率均80%-120%之间,检测低限铀和钍均为0.025 mg/kg。

The trace amounts of Th and U in seven categories of food （flour,sweet potapo ,bananas,vegetables ,pork, squid,milk powder） were determined by inductively coupled plasma mass spectrometry （ICP-MS）. We Choosed the best instrument measurement parameters and the bismuth （Bi） as an internal standard element to compensate matrix effects and instrument sensitivity drift. Digesting samples with nitric acid, ICP-MS could directly measure the Th and U in foods, with recovery of 80% - 120% , and low detection limits of uranium and thorium were 0. 025 mg/kg respectively.