微波等离子体飞行时间质谱的一些研究与进展

Some Innovative Features in Microwave Plasma Source Based Time-of-Flight Mass Spectrometry

简述等离子体源飞行时间质谱(P-TOF-MS)的一些研究进展,重点介绍了近年来开发的质谱等离子体源,特别是对氦微波等离子体源的"离锥"进样技术,新型辉光放电-微波诱导等离子体级联源(GD-MIP),减压微波等离子体源以及用于飞行时间质谱的微型放电源等的特点及应用进行了描述,并对离子源装置及特性进行了全面分析。

Over the past decades,plasma source based time-of-flight mass spectrometry（TOF-MS） has emerged as a powerful technique for trace elemental analysis.The technique possesses several significant advantages over conventional instruments,such as better ion transmission efficiency,capability of transient signal analysis,and ability to acquiring multiple isotopes at near same time.However,most plasma source based TOF-MS work is limited to inductively coupled plasma（ICP） and glow discharge（GD） sources,with only argon used as working gas for elemental analysis.Noticing these limitations of the technique,research work in our group has focused on development and exploration on alternative plasma sources for TOF-MS.This paper brief some innovative features of our research work in alternative plasma sources for TOF-MS.These features include a uniquely developed ＂off-cone＂ sampling technique with helium-based microwave plasma source,a GD-MIP tandem ion source,a reduced pressure microwave plasma source,and a miniature micro-discharge based plasma source for TOF-MS.Several working gases,argon,helium,and mixed gases,were tested with these plasma sources for various applications from elemental determination to organic analysis.Some unique features are demonstrated,such as dramatically reducing background peaks without sacrificing analyte signal intensity with ＂off-cone＂ sampling,significantly enhanced signal peaks with GD-MIP tandem source,effectively organic analysis and elemental speciation with reduced pressure MIP source,and amazing molecular fragmentation with micro-discharge source.