应用电感耦合等离子质谱测定饲料中的微量元素的研究

应用电感耦合等离子体质谱(inductively coupled plasma-mass spectrometry，ICP-MS)测定饲料中铜、锌、铁、锰、铬、镉、铅、砷和硒等微量元素的方法。考察了谱干扰、基体效应和记忆效应等因素对测量的影响。在优化的条件下，方法检出限达到10-9级，线性范围达到3个数量级，线性相关系数高于0.999。将该方法用于实际样品的测定，小麦粉标准品中各元素的测定值与标示量能很好的吻合，配合饲料中微量元素的回收率在86％～115％，相对标准偏差(RSD)≤8.2%(n=6)。预混合饲料中微量元素的含量与国家标准方法测得值能够较好的吻合。该方法与传统方法相比，具有简单快速，灵敏度高，能够同时测定多种元素的优点。

Study on the Method of Using ICP-MS to Determine Microelements in the Animal Feed

The method for the determination of microelements such as Cu, Zn, Fe, Mn, Cr, Cd, Pb, As and Se in the animal feed by inductively coupled plasma-mass spectrometry was developed. The operation parameters, spectrum interference, matrix effect and memorial effect were studied in detail. Under optimal condition, the detection limits of these nine elements were from 2.03 x 10(-3) to 3.17 microg x L(-1), and the linear range was over three orders with a correlation coefficient above 0.999. This method was applied directly to determine microelements in real samples involving the standard wheat powder, formular feed and pre-mix feed. The determination results of microelements in the standard wheat powder accorded with reference results. The recovery of microelements in the formular feed was from 86% to 115%, and the relative standard deviations < or = 8.2% (n = 6). The results of elements content in the pre-mix feed were identical with those determined by national standard method. This method is simple, sensitive, accurate and can perform simultaneous multi-elements determination compared with conventional method of animal feed determination. The results were satisfactory.