摘要
目的：建立快速准确灵敏的微波消解-原子荧光光谱法用于大米中痕量汞的测定。方法：采用硝酸/双氧水微波消解体系对样品进行预处理,利用原子荧光光谱法测定大米中的痕量汞。结果：在优化的最佳消解条件和反应检测条件下：硝酸/水/双氧水的配比为4：4：2;还原剂硼氢化钾（KBH4）浓度为0.3%;灯电流20 mA;载气流量300 ml/min;酸性介质为5%的盐酸,汞在浓度范围为0.1～50.0μg/L内线性关系良好,线性相关系数为0.9999,检出限为0.0114μg/L,样品加标回收率在98.9%～105.9%之间,四次平行测定相对标准偏差小于6.6%。结论：该方法简便快速、准确灵敏,适用于大米中痕量汞的测定。测定结果显示,宁波市场上随机抽取的5种大米样品中汞含量均低于国家标准,对于人们食用是安全的。
Objective：To establish a rapid,precise and sensitive method for the trace determination of mercury in rice by microwave digestion coupling with atomic fluorescence spectrometer approach.Methods：After a pretreatment with nitric acid/hydrogen peroxide microwave digestion system,we used atomic fluorescence spectrometer methodology to determine trace mercury in rice.Results：Under the optimized digestion and detection conditions： nitric acid/water/hydrogen peroxide ratio,4：4：2;KBH4 concentraton,0.3%（w/w）;lamp current,20 mA;flow rate of carrying gas,300 ml/min;carrying flow,5% HCl,wide linear relationship was achieved in the range of 0.1~50.0 μg/L with relative coefficient of 0.9999 and the detection limit was estimated to be 0.0114 μg/L.We got satisfied recovery rates of spiked samples of 98.9% to 105.9% with RSD of four replicate experiments less than 6.6%.Conclusion：The present method is precise,rapid and sensitive enough for determination of trace mercury in rice.The detection results indicate that rice in Ningbo market is mostly safe.
出处
《中国卫生检验杂志》
CAS
2010年第3期519-521,共3页
Chinese Journal of Health Laboratory Technology
