电化学氢化物发生技术在原子光谱分析领域的应用进展  

The Application and Development of Electrochemical Hydride Generation in Atomic Spectrometry Analysis

作　　者：祖文川[1] 汪雨[1] 武彦文[1] 陈舜琮[1] 

机构地区：[1]北京市理化分析测试中心,北京市食品安全分析测试工程技术研究中心,北京100089

出　　处：《岩矿测试》2014年第2期168-177,共10页Rock and Mineral Analysis

基　　金：国家重大科学仪器设备开发专项(2011YQ15004011;2011YQ140147);北京市财政资金支持项目(PXM2013_178305_000005);北京市科学技术研究院改革与发展专项(2013)

摘　　要：电化学氢化物发生法（EcHG）是原子光谱仪发展的一种实用气态进样技术.该技术通过采用电化学发生池内的电极反应代替传统化学还原的方法来生成氢化物和汞蒸气.与传统的化学法硼氢化钾（钠）-酸氢化物发生体系相比,EcHG技术仅需要支持电解质,氢化物（汞蒸气）在阴极室内发生后直接导入原子光谱仪的原子化器,在降低分析成本和溶液配制时间的同时,分析过程引入的空白值也大大降低,更加绿色环保.近年来,EcHG原子光谱分析已经从单一的元素总量测定发展到元素形态分析,从微量元素分析发展到痕量超痕量元素分析,发生元素涵盖了砷、硒、铅、镉、锡、锑、锗和汞,应用范围涉及食品、环境、烟草、饲料等实际样品.EcHG技术应用于原子荧光光谱分析,特征元素检出限能够达到0.1 μg/L级（汞为ng/L级）;应用于原子吸收光谱与等离子体发射光谱分析,适用元素检出限能够达到μg/L级,相对标准偏差均小于10％,回收率在90％ ～ 110％之间.EcHG技术相关的机理研究也已经起步,这为该技术在原子光谱分析领域的应用提供了理论基础.但是,EcHG技术的分析范围目前仅限于部分元素的无机态,对元素的有机形态分析是本领域发展的难点之一.本文提出,关于电化学氢化物发生的机理研究、电化学流通池结构的优化、形态分析范围的拓展等将成为该技术的重要发展方向.Electrochemical hydride generation （EcHG） is an effective gas sampling method developed for atomic spectrometers.Electrode reactions are adopted in an electrochemical cell to generate hydride and mercury vapor in the cathode chamber for EcHG instead of traditional chemical reducing method.Compared with the traditional KBH4（NaBH4）-acid chemical system,no other chemical reagents but the supporting electrolyte is needed for EcHG as electron transfer plays the reducing role instead of the reducing reagents.For EcHG,hydride and mercury vapor are directly led to the atomizer from the cathode chamber for determination.The analysis price and time for making up solutions are decreased in large degree meanwhile the blank value introduced from the analytic process is reduced remarkably for EcHG.Moreover,EcHG is lower pollution and more environmental friendly due to none chemical reagent used.Recently,rapid development has been made for atomic spectrometry analysis including Atomic Fluorescence Spectrometry （AFS）,Atomic Absorption Spectrometry （AAS）,Atomic Emission Spectrometry （AES） coupled with electrochemical hydride generation.The analytical range for this technology has been extended to speciation analysis from only total amount of element analysis.The requirement for trace or even ultra trace detection has gradually been satisfied instead of merely micro-analysis.As for the analytical performance,most of the regular chemical hydride generated elements are covered,including As,Se,Pb,Cd,Sn,Sb,Ge and Hg.Generally,μg/L level can be achieved for the detection limits of characteristic elements by EcHG coupled with AAS and Inductively Coupled Plasma-Atomic Emission Spectrometry （ICP-AES）.While for EcHG-AFS,it can be reduced to 0.1 μg/L （ng/L level for mercury）.The relative standard deviations are lower than 10%.The spiked recoveries are 90%-110% and determination results for standard matters are favorable.A series of real samples （foods,tobacco,fodder,etc） were successfully analyzed by this t

关 键 词：电化学氢化物发生 原子荧光光谱 原子吸收光谱 等离子体发射光谱 研究进展 

分 类 号：O657.63[理学—分析化学]