电化学还原气态进样-原子荧光光谱法测定海产品中总汞  

Determination of total mercury in seafoods by atomic fluorescence spectrometry assisted with electrochemical reducing vapor generation sampling technique

作　　者：祖文川[1] 汪正浩[2] 

机构地区：[1]北京市理化分析测试中心,北京100089 [2]北京师范大学化学学院,北京100875

出　　处：《分析试验室》2015年第8期926-929,共4页Chinese Journal of Analysis Laboratory

基　　金：国家科技部重大科学仪器设备开发专项(2011YQ15004011;2011YQ140147);北京市科学技术研究院青年骨干计划(201313)资助

摘　　要：建立了电化学还原气态进样-原子荧光光谱法测定海产品中的总汞的方法。海产品中不同形态的汞经消解后全部转化为无机汞,经电化学还原原子化后由氩气导入原子荧光光度计原子化器中实现定量分析。实验对电化学流通池结构以及影响分析灵敏度的电解电流、载气流量等实验条件进行了优化。优化条件下,在0.5~7.0μg/L汞浓度范围内,荧光值与浓度之间线性关系良好;该法汞的检出限为2.8 ng/L;2μg/L汞标液6次平行测定相对标准偏差2.0%;加标回收率在91.2%~98.7%之间。该法可应用于北京市购4种海产品中总汞含量的测定。A method for determination of total mercury in seafoods by electrochemical reducing vapor generationatomic fluorescence spectrometry was established in this work. Mercury with different states can be transferred to be inorganic species using a wet digestion method,and then the mercury atoms can be acquired during an electrolysis process. After the electrochemical reducing atomizing,the mercury vapor was transported into the atomizer of the atomic fluorescence spectrometer by the carrier gas and thus the content can be quantitatively analyzed. The influence factors and the instrumental parameters on the detecting sensitivity,including the electrochemical chamber configuration,the electrolytic current,the carrier gas velocity,etc.,were investigated.Under the optimized conditions,the fluorescence intensity can be increased with the mercury concentration linear up from 0. 5 μg/L to 7. 0 μg/L. The detection limit of mercury for this method was 2. 8 ng/L. And the relative standard deviation calculated from six parallel tests for 2 μg/L Hg standard solution was 2. 0%,and the spiked recoveries were between 91. 2 % ~ 98. 7%. Four different types of commercial seafood samples purchased from the Beijing market were determined by this method,and reliable results were acquired. The analytic process is rapid and can be easily performed,while the results are accurate and reliable. Compared with the traditional chemical reducing cold vapor generation technique,the dependence of the purity and stability of chemical reductants can be effectively decreased.

关 键 词：电化学还原 蒸气发生 原子荧光光谱 总汞 海产品 

分 类 号：TS254.7[轻工技术与工程—水产品加工及贮藏工程]