微波消解-电感耦合等离子体质谱法测定酱油中的铅和钠含量

Determination of lead and sodium in soy sauce by microwave digestion-inductively coupled plasma mass spectrometry

中文关键词:  电感耦合等离子体质谱法  微波消解  酱油  铅  钠

英文关键词:inductively coupled plasma mass spectrometry  microwave digestion  soy sauce  lead  sodium

中文摘要:

      目的 建立微波消解和电感耦合等离子体质谱(inductively coupled plasma mass spectrometry, ICP-MS)联用同时测定酱油中高含量元素钠(Na)和低含量元素铅(Pb)的检测方法。方法 根据酱油高盐分性质, 选取合适同位素和电子稀释参数、采用碰撞池He模式及内标校正等技术消除干扰, 用微波消解对样品进行前处理, 采用电感耦合等离子体质谱仪同时检测Na和Pb含量。结果 Na和Pb在0~800 mg/L、0~25 μg/L质量浓度范围内线性关系良好, 其线性相关系数均为0.9992, Pb和Na的检出限分别为0.02、3 mg/kg, 相对标准偏差(relative standard deviation, RSD)小于5%, 回收率为96.2%~112%。结论 此方法能有效消除干扰, 准确、简便、快速, 适用于酱油中Pb和Na的同时测定。

英文摘要:

      Objective To establish a method for determination of sodium and lead in soy sauce by inductively coupled plasma mass spectrometry (ICP-MS). Methods According to the high salinity of soy sauce, appropriate isotope and electronic dilution parameters were selected, He mode of collision cell and internal standard correction were used to eliminate interference. The sample was pretreated by microwave digestion, and contents of Na and Pb were simultaneously detected by inductively coupled plasma mass spectrometry. Results Na and Pb had good linear relationships in the rage of 0-800 mg/L and 0-25 μg/L, respectively, and the linear correlation coefficients were both 0.9992. The limits of detection of Pb and Na were 0.02 and 3 mg/kg, respectively. The relative standard deviations (RSDs) were less than 5%, and the recoveries were 96.2%-112%. Conclusion This method can effectively eliminate interference, and is accurate, simple and rapid, which is suitable for simultaneous determination of Pb and Na in soy sauce.