This award funds acquisition of a high-performance liquid chromatography mass spectrometer (HPLC-MS) with a fraction collector to identify, quantify and isolate organic compounds for geologic matrices. The proposed acquisition will complement gas chromatographic (GC) and GC-isotope ratio mass spectrometry (GC-IRMS) instrumentation already in use. It will allow analyzing low volatility, non-GC-amenable compounds. The fraction collector will allow the PIs to purify and isolate compounds which can then be subjected to carbon isotope analysis. The instrumentation will be used for reconstructing past terrestrial, lacustrine and marine temperatures from sediment archives using ether-bound archaeal and bacterial lipids; isolating and purifying target "biomarker" compounds for stable isotope analysis using natural abundance or labeling to better understand biogeochemical cycling; and assessing organic material provenance and age in a varied depositional settings using compound-specific radiocarbon dating which will provide new constraints on the carbon cycle and the age of past sediment deposits. The underlying theme to research proposed is using compound-specific biomarkers to constrain and interpret geological data. Using HPLC-MS will provide analytical range to "new" groups of biomarkers not able to be measured by GC or other more standard techniques. Purification and isolation procedures will be developed using the fraction collector which will greatly reduce analytical labor. The instrument will be shared by several PIs and across the Department. The instrument will expand capabilities in several disciplines. Current programs are established for attracting undergraduates and disadvantaged students. Two lab-based courses will also directly benefit. The PI will retain overall supervision of the instrument. A mass spectrometry facility manager will be responsible for day-to-day scheduling. Annual maintenance and consumables costs will covered by per sample fees. Pilot studies and method(s) development will be scheduled on a case-by-case basis. The PI has two years of full-time technician support.
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" provided matching funds for the acquisition of a high-performance liquid chromatography mass spectrometer (HPLC-MS) with intelligent fraction collection capabilities for the identification, quantification and isolation of organic compounds from geological and biological samples at the University of Texas at Austin. This instrumentation provides unique new analytical capabilities at the University of Texas and has stimulated new interdisciplinary collaborations between researchers in the fields of climate and sedimentary geology, hydrogeology and biogeosciences and biology. Among the ongoing projects utilizing this instrumentation are: (a) the analyses of the lipids of temperature sensitive organisms preserved in marine and lacustrine systems to reconstruct past temperatures, (b) analysis of lipids for reconstruction of environmental conditions associated with the evolution of large mountain belts, (c) isolation of lipids for tracing of the movement and residence time of organic matter through the terrestrial, aquatic and marine environment and its eventual fate of organic carbon on the continental shelf, (c) providing unique insights into life in extreme environments using new techniques unavailable only a few years ago. Preliminary results from a study of archaeal lipids in the sediments from Lake Titicaca provide the most robust proxy temperature record for South America produced to date, and show dramatic cooling of at least 5-6 degrees during the last glacial maximum, a rapid warming coincident with deglaciation of the Andes and an abrupt return to cold conditions during the Younger Dryas event. These data document the large climate sensitivity of the tropical Andes and suggest that both global and regions factors can drive these changes nder differing mean climate states. They provide new insights into the dominant controls on tropical cliamte variability over the last ca.30,000 years. In addition to stimulating interdisciplinary research collaborations associated with the above projects via increased accessibility to instrumentation, the project has provided new research and training opportunities for six graduate students and two undergraduates, including five female students and two students from underrepresented groups. Furthermore, via participation in the University of Texas summer Research and Education opportunities for Undergraduates (REU) program, two additional undergraduate students from small college, non-research institutions (both female, three from underrepresented groups) will have opportunities (summer 2011) to utilize this instrumentation in summer research projects. Plans to incorporate the instrumentation into small research-centered class exercises in organic geochemistry and paleoclimatology are ongoing, and PI Shanahan has plans to develop classroom exercises using the LC-MS system as part of his participation in the summer 2011 NSF Early Career Geoscience Faculty Workshop.
