砷的微波等离子体炬质谱行为探究  

Study of the Behavior of Arsenic in Microwave Plasma Torch-Mass Spectrometry

作　　者：唐子阳 李国霖 李典 董露露 王丽 宋丽丽[1] 吴德波 李伯平[3] 郭冬发[3] TANG Zi-yang;LI Guo-lin;LI Dian;DONG Lu-lu;WANG Li;SONG Li-li;WU De-bo;LI Bo-ping;GUO Dong-fa(Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation,East China University of Technology,Nanchang 330013,China;School of Chemistry,Biology and Materials Science,East China University of Technology,Nanchang 330013,China;Beijing Research Institute of Uranium Geology,Beijing 100029,China)

机构地区：[1]东华理工大学,江西省质谱科学与仪器重点实验室,江西南昌330013 [2]东华理工大学化学生物与材料科学学院,江西南昌330013 [3]核工业北京地质研究院,北京100029

出　　处：《质谱学报》2023年第4期519-529,I0003,共12页Journal of Chinese Mass Spectrometry Society

基　　金：国家自然科学基金地区基金(21964002);江西省自然科学基金青年基金(20202BABL213020);东华理工大学博士启动基金(DHBK2020002);核能开发项目(测H2002)。

摘　　要：本研究将氢化物发生(HG)技术与微波等离子体炬(MPT)相结合,开发了一种针对砷元素的快速、灵敏的常压直接质谱分析方法,即氢化物发生-微波等离子体炬质谱(HG-MPT-MS)法,并在此基础上系统探究了不同电离条件下砷的质谱行为。在正、负离子模式下,砷具有显著区别于电喷雾电离(ESI)、电感耦合等离子体(ICP)等电离技术的特征质谱峰(如可实现分子电离,易与硝酸根等离子结合,甚至形成砷酸根离子的二聚体等),且背景干净、信号响应强,适用于对复杂样品中的微量砷进行直接质谱分析。此外,还研究了盐酸浓度对氢化砷信号强度和电离行为的影响,以及微波功率对砷电离行为的调控。与ICP相比,MPT在分析砷元素时具有极低的功耗和氩气消耗、软电离以及能量连续可调控等优势。结果表明,在1~500μg/L浓度范围内,砷浓度与其信号强度具有良好的线性关系,线性相关系数(R2)大于0.998,检测限为0.02μg/L,且各待测离子的信号稳定性和峰形均较好。Based on the coupling of hydride generation(HG)and microwave plasma torch(MPT),a rapid and sensitive method of hydride generation-microwave plasma torch-mass spectrometry(HG-MPT-MS)for arsenic under atmospheric condition was developed.The mass spectral behavior of arsenic under different ionization conditions was investigated.In both positive and negative ion modes,arsenic displayed characteristic mass spectrum peaks,which was significantly different from electrospray ionization(ESI),inductively coupled plasma(ICP)and other common ionization techniques.HG-MPT-MS enabled ionization of analytes at molecular level,and it formed adduct ions with NO3-,and even dimers of arsenate ions.Due to the combination of hydride generation and microwave plasma torch,the background noise and the signal intensity of analytes were greatly improved.Therefore,this method was suitable for direct mass spectrometry analysis of trace arsenic in complex samples.In addition,the influence of HCl concentration on the signal intensity,and the regulation of arsine generation behavior by microwave power were studied.Compared with ICP,microwave plasma torch showed more obvious advantages on the analysis of arsenic,such as extremely low power and argon consumption,soft ionization and continuous energy regulation.The total ion chromatography(TIC)and the extracted ion chromatography(EIC)of all analytes displayed good signal stability and peak shape.In addition,arsenic concentration and its signal intensity showed a good linear relationship(R2>0.998)in the concentration range of 1-500μg/L,and the detection limit was 0.02μg/L.This method was applied to analysis of a reference water standard and two real water samples of lake water and river water.The results showed that the determined value was in agreement with the certified value for the reference standard.Spiked recoveries of the river water and lake water samples ranged from 95.0%to 105.0%with the relative standard deviation(RSD)of 8.0%-11.0%.On the other hand,the commonly used hydride generatio

关 键 词：砷 氢化物 微波等离子体炬(MPT) 直接质谱分析 电感耦合等离子体(ICP) 电喷雾电离(ESI) 

分 类 号：O657.63[理学—分析化学]