金负载木基顶空固相微萃取-热脱附原子吸收光谱法快速测定水中汞  

Detection of Mercury in Environmental Water by Thermal Desorption-Atomic Absorption Spectrometry Coupled with Gold-immobilized Wood Based Solid Phase Microextraction

作　　者：马旭 张芳 潘佳钏 郭鹏然[2] 欧阳钢锋[1] MA Xu;ZHANG Fang;PAN Jia-Chuan;GUO Peng-Ran;OUYANG Gang-Feng(School of Chemistry,Sun Yat-sen University,Guangzhou 510275,China;Guangdong Provincial Engineering&Technological Research Center of Online Monitoring for Aquatic Environment, Guangdong Provincial Key Laboratory of Emergency Test for Dangerous Chemicals,Guangdong Institute of Analysis, Guangzhou 510070,China)

机构地区：[1]中山大学化学学院,广州510275 [2]广东省测试分析研究所,广东省化学危害应急检测技术重点实验室,广东省水环境污染在线监测工程技术研究中心,广州510070

出　　处：《分析化学》2018年第12期1975-1981,共7页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(No.21777150);广东省科技计划项目(Nos.2015A020218001,2016B020240006,2017A040405040);广州市科技计划项目(No.201803030042)资助。

摘　　要：以负载金离子的木基牙签作为一次性固相微萃取采样器,建立了顶空固相微萃取-热脱附便携式原子吸收光谱仪联用快速测定环境水样中痕量汞的方法。实验考察了金离子浓度、负载时间、萃取时间、振荡速度以及盐效应对萃取效率和测定结果的影响。结果表明,样品现场检测20 min即可完成;方法的线性范围为0.25～10.0 ng/mL,相关系数大于0. 998,汞离子的检出限为0. 03 ng/mL;对于1. 0 ng/mL的加标水样,使用8支固相微萃取采样器测量的相对标准偏差为2.1%;水样标准参考物质的测定与标准值一致。采用本方法对自来水、湖水、海水和制革废水4种汞加标后的实际水样进行测定,添加水平为1.0、5.0和10.0 ng/mL,加标回收率分别为89.6%～92.9%、90.2%～95.3%和93.8%～106.2%。本方法自制的木基固相微萃取采样器成本低廉、制备过程简单、采样器间重现性好,方法测定速度快、准确性高,适合于水中汞污染的原位筛查与风险评估。A novel solid phase microextraction(SPME)sampler consisted of gold-immobilized wood-based toothpick was developed for the rapid detection of mercury in environmental water samples via direct analysis in thermal desorption-atomic absorption spectrometry(TD-AAS).Several parameters affecting headspace extraction efficiency of mercury such as gold ions concentration,loading time,extraction time,shaking rate and salt effect,were investigated.The results showed short field analytical time(less than 20 min),good linearity(R 2≥0.998)in the range of 0.25-10 ng/mL with the detection limit of 0.03 ng/mL(S/N=3).Furthermore,the relative standard deviations(RSDs)for the sampler-to-sampler reproducibility of eight as-prepared SPME samplers were 2.1%at the spiking level of 1.0 ng/mL.The detection result was in agreement with the certified value of water reference material.The method was applied to analysis of four water samples including tap water,lake water,sea water and waste water with satisfactory spiked recoveries of 89.6%-92.9%,90.2%-95.3%and 93.8%-106.2%at 1.0 ng/mL,5.0 ng/mL and 10.0 ng/mL spiking level,respectively,demonstrating the practicality of the proposed method for the determination of mercury in environmental water samples.Characterized by low cost,ease of fabrication and excellent sampler-to-sampler reproducibility,the homemade wood-based SPME sampler in combination with portable TD-AAS is suitable for the on-site screening and risk identification of aqueous mercury contamination.

关 键 词：汞 木基固相微萃取 金负载 热脱附-原子吸收光谱 水样 

分 类 号：O657.31[理学—分析化学] X832[理学—化学]