电喷雾萃取电离质谱法(LTQ-EESI-MS)快速筛选水环境中重金属

Rapid Screening of Heavy Metals in Water Environment by extractive electrospray ionization mass spectrometry(LTQ-ESI-MS)

为解决拥有复杂基体的水环境中重金属快速检测问题,建立了电喷雾萃取电离质谱法(LTQ-EESI-MS)快速筛选水环境中重金属的方法。含重金属的样品液滴与络合剂EDTA/CyDTA水溶液在EESI源装置上发生在线液-液微萃取,并使萃取与离子化同时进行,然后形成EDTA/CyDTA-重金属络合物阴离子以供质谱分析,检测到的天然同位素比和碎裂方式确证了利用LTQ-EESI-MS法可成功检测并分辨出EDTA/CyDTA-重金属络合物。该方法基本无需样品预处理,能简单、快速地对复杂基体样品进行直接质谱分析,定性测出重金属离子Cu、Zn、Pb、Cd,非常适合大批量样品的分析。该方法是质谱仪器在无机物检测的一种尝试,也可为水环境中重金属污染物的污染筛查和快速监测提供重要技术支持。

The heavy metals pollution in environment is becoming increasingly prominent,and the determination of heavy metals requires complicated pre-treatment which is time-consuming and laborious.In order to determine the heavy metals with complex matrix in water environment rapidly,a screening method for heavy metals in water environment was established by using extractive electrospray ionization mass spectrometry（LTQ-EESI-MS）.Online liquid-liquid microextraction occurrs between droplets of ethylenedinitrilo（EDTA）or trans-1,2-Diaminocyclohexane-N,N,N＇,N＇-tetraacetic acid hydrate（CyDTA）and heavy metal containing sample solutions on extractive electrospray ionization（EESI）source device.And make the extraction and ionization were done at the same time and the mass analysis were carried out after the formation of EDTA/CyDTA-heavy metal complex anion.Natural isotope ratios and fragmentation pattern confirmed that EDTA/CyDTA-heavy metal complexes can be detected and distinguished successfully by using LTQ-EESI-MS method.The feature of this method is as follows：the determination of Cu,Zn,Pb and Cdwere finished without any sample pretreatment,and the mass spectrometric analysis of the complex matrix samples can be done directly,simply and quickly.This method is very suitable for the analysis of large numbers of samples,and provides an attempt on mass spectrometry in the inorganic detection,and can also be an important technical support for the rapid screening and monitoring of heavy metals pollutants in the water environment.