电感耦合等离子体-质谱法测定居民肉类膳食中碘的方法研究

Determination of dietary iodine in meat by inductively coupled plasma-mass spectrometry

目的建立测定肉类膳食中碘的电感耦舍等离子体-质谱法（ICP．MS），并对我国14个省份居民肉类膳食进行测定。方法样品用四甲基氢氧化铵-双氧水溶液在60℃超声提取3h，冷冻脱脂、甲酸沉淀蛋白后。以128Te为内标元素，ICP—MS法测定肉类膳食中碘含量。结果方法线性范围为1～200μg／L，r=0．9998，检出限2．3μg／kg，RSD≤5．7％（n=7），加标回收率为80．0％～96．6％。结论该方法高效、可行，适用于肉类膳食中碘的测定。为居民肉类膳食中碘含量监测工作提供技术支持。

Objective The method for the determination of dietary iodine in meat was developed by inductively coupled plasma-mass spectrometry （ICP-MS）. Methods The samples were extracted by tetramethylammonium hydroxide and hydrogen peroxide in uhrasonic bathing at 60℃ for 3 h and analyzed by ICP-MS after removing fat and protein. 12STe was used to eliminate the matrix interference. Results Under the optimal conditions, this method showed excellent linearity in the range from 1 to 200 μg/L with a correlation coefficient of 0. 999 8. The limit of detection was 2. 3 p.g/kg. The relative standard deviations were no more than 5.7% （n = 7）. The average recoveries of iodine were in the range from 80. 0% to 96.6%. Conclusion This method was efficient and practicable for determining dietary iodine in meat.