氢化物发生-原子荧光法测定食品添加剂碳酸钙中的铅

摘要

A method has been established for the determination of lead in food additive calcium carbon-ate by HG-AFS.The effects of the work conditions of instruments,the acidity of liquid carrier,the concentration of reducing agent,the quantity of oxidant and co-existent elements are investigated in details.Under the optimal conditions,the calibration curve is linear in the range of 0~60μg/L (r=0.9998)with detection limit of 3.2μg/kg.The relative standard deviation(RSD)is 0.74% for eleven consecutive measurements of 10μg/L lead standard solution.The average recoveries are 95.20%~104.3% at the spiking levels of 12,24,36μg/L of lead and the relative standard deviations(n=6)are no more than 2.53 when applied in the three actually samples.The results between the method and national standard method are basically consistent.%建立了氢化物发生-原子荧光光谱法测定食品添加剂碳酸钙中铅的分析方法。考察了仪器工作条件、载流的酸度、还原剂浓度、氧化剂的用量以及共存元素对测量体系的影响。在优化实验条件下，该方法的线性范围为0～60μg/L（r＝0．9998），方法检出限为3．2μg/kg，相对标准偏差（n＝11）为0．74％。以3个批次的样品为例，加入铅浓度分别为12，24，36μg/L，每个浓度进行6次平行测定，铅的回收率介于95．20％～104．3％之间，RSD ≤2．53。与国家标准方法分析结果进行比较，两种方法测定值基本一致。