电感耦合等离子体质谱法测定地热水中的碘

Determination of iodine in thermomineral waters by inductively coupled plasma-mass spectrometry

电感耦合等离子体质谱测定地热水中碘含量时,高盐溶液会导致仪器灵敏度迅速降低,同时碘存在严重记忆效应。通过优化仪器测定条件,在较低雾化器流量条件下,在线内标元素(Rh)进行基体校正,选用1.5%(体积分数)的稀NH3.H2O介质消除碘的记忆效应,直接取样对样品测定。结果显示:在优化条件下,碘的检出限0.10μg·L^(-1),相对标准偏差(RSD,n=12)为4.9%,加标回收率为94.4%~110.0%。该方法具有操作简便、检出限低、检测速度快、结果准确等优点。

When Inductively Coupled Plasma-Mass Spectrometry(ICP-MS)was applied to the determination of iodine in thermominer water,the high salt solution causes the sensitivity of the instrument to decrease rapidly,and the iodine memory effect is serious.By optimizing the determination conditions of the instrument,Rh was used as on line internal standard and under the condition of low bebulizer gas flow,and weak ammonia solution(1.5%)was selected to eliminate the memory effect from iodine.Thermomineral waters were directly determined by ICP-MS.According to the results,The detection limit of the method was 0.10μg·L^(-1),a relative standard deviation(RSD,n=12)of 4.9%,and the addition recoveries were between 94.4%and 110.0%,under optimum conditions.These procedures were convenient to follow,low detection limit.Furthermore,the results are of short detection time,large linear range and extremely high precision.