The specific goals of this proposal are to develop state-of-the-art ultra-trace analytical methods for elemental analysis of environmentally important samples. Ultra-trace analyses will be developed with speciation, a necessity for reliable risk assessment. Chromatographic techniques will be combined with plasma source mass spectrometry (plasma MS) to provide elemental speciation for pollutant or potential pollutant inorganic, organic and organometallic compounds. By coupling plasma MS detection with supercritical fluid extraction and gas, liquid, or supercritical fluid chromatography (GC,LC, sometimes referred to as HPLC, or SFC, respectively), a variety of important environmental sample types can be determined at picomole and possibly lower levels. Detection after liquid chromatographic separations will be further enhanced through post-column hydride generation when appropriate. An additional attraction with plasma MS is that isotope information is simultaneously available. Studies will involve research involving ion formation and transport that will lead to better methods. While high resolution is expected from the chromatographic types employed, multiple element monitoring, with plasma MS selectivity, provides much additional information, since several chromatograms can be obtained from one sample injection (one for each elemental mass monitored). Additional plasma mass spectrometric methods will be initiated or further investigated. Since several plasma types have been investigated to date in these laboratories for their analytical utility, more fundamental characterization is necessary plus further studies to minimize matrix effects are warranted. Other studies will include glow discharge mass spectrometry for solid introduction of environmental samples and electrothermal vaporization for microliter volume sample introduction plus to minimize certain interferences. Also further investigation of plasmas for their potential to produce structural information as LC-MS sources to yield qualitative and quantitative results, will be undertaken. The importance of and approaches to these problems are detailed within.
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