MRI: Acquisition of instrumentation to advance our understanding of environmental processes through characterization of the organic compounds in different environmental reservoirs

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This project will purchase an off-the-shelf instrument that has an unprecedented capability to separate individual molecules found in complex matrices and more precisely access their composition (through accurate measurement of mass). The environmental matrices that will be studied in this research and the innovative sample processing methods that will be employed to reduce the natural complexity of relevant samples represents a novel application of this instrument. Examples of new knowledge that will be created include a better understanding of how contaminants are transformed in the environment, how microscopic organisms regulate bloom dynamics through communication, and how known biochemicals are transformed into molecules that can be preserved on long timescales, thus contributing to the production of oxygen and the sequestration of carbon dioxide. Such a molecular-level understanding of these processes is essential for determining the environmental factors that regulate them and how these processes may respond in the future. The data produced with this instrument will be publically available as a mass spectral library that will be of use to other fields including drug discovery, petroleum research, and metabolomics. In addition, several graduate students and post doctoral researchers will receive hands-on access to this instrument, providing valuable training that will prepare them well for careers in both academia and industry.This project will acquire a comprehensive gas chromatograph (GC×GC) coupled to a Pegasus HRT (High Resolution TOF) Mass Spectrometer (MS), which will be initially utilized to examine the diversity of organic molecules accumulating in aquatic environments and also to identify degradation products of chemical contaminants accumulating in various environment matrices. Organic geochemistry and environmental chemistry necessarily deals with complex matrices where thousands to millions of compounds derived from various sources, acted upon by abiotic and biotic processes, accumulate on short to millennial (and beyond) timescales. Chemical structures of these compounds carry critical information regarding source, mechanisms of transformation and residence time. Access to advanced analytical instrumentation continues to increase access to such information. Comprehensive gas chromatography, together with advanced mass deconvolution afforded by the high scan rates of the identified instrument (200 full mass range mass spectra per second) enables unprecedented ?separation? of complex mixtures of organic molecules. Additionally, the sub-ppm mass accuracy greatly enhances the likelihood of unknown compound identification. Together these two features make this instrument unique. Knowledge about the processes that shape the chemical composition of various environmental reservoirs will scale with the extent to which these complex samples can be chemically described. As such, there is a significant reward associated with comprehensively characterizing the chemical composition of such samples.