BS ISO 20647婴儿配方奶粉和成人营养配方奶粉-总碘的测定-电感耦合等离子体质谱法(ICP-MS)

BS ISO 20647 Infant formula and adult nutritionals-Determination of total iodine-Inductively coupled plasma mass spectrometry(ICP-MS)

本文全文译自国际标准BS ISO 20647:2015(E)Infant formula and adult nutritionals-Determination of total iodine-Inductively coupled plasma mass spectrometry(ICP-MS)。该标准规定了ICP-MS法测定婴儿配方奶粉和成人营养配方奶粉中总碘的测定方法。所有粉末状样品在分析前需要按一定比例用水稀释进行复原,即食样品(RTF)无需复原。称取约一定质量的复原试样,加入5%KOH溶液,在烘箱或微波消解装置中105℃±5℃进行消解,微波消解时消解容器盖子应稍微松开。消解完成后加入碘稳定剂-氨水-Na_2S_2O_3溶液,定容,混匀。取适量消解液过1μm滤膜,用141Pr作内标,ICP-MS直接测定滤液中碘的含量。该方法线性范围0.25~100ng/m L,能快速、准确、灵敏地测定婴儿和成人配方奶粉中总碘含量。

This paper is the translation of BS ISO 20647：2015： Infant formula and adult nutritionals-Determination of total iodine-Inductively coupled plasma mass spectrometry （ICP-MS）. This standard specifies the method for the determination of total iodine in infant formula and adult nutritional formula by ICP-MS. All powdered samples are required to be analyzed on a reconstituted basis. After weighing a certain quality of the reconstituted sample, 5% KOH solution is added, then digested in the oven or microwave digestion device at 105 ℃±5 ℃. Microwave digestion container lid should be slightly released. After the completion of digestion, the iodine stabilizer-ammonia-Na2S2O3 solution is added, whereafter, adding water to the volume, and mixing thoroughly. Taking an appropriate amount of the digestion through 1 μm filter, the filtrate is determined by ICP-MS with ^141Pr as internal standard. The method has a linear range of 0.25～100 ng/mL, which can quickly, accurately and sensitively determine the total iodine content in infant formula and adult nutritionals.