Acquisition of a Gas Chromatography/Time of Flight-Mass Spectrometry (GC/TOF-MS) System for Ultra-High Resolution Molecular Stratigraphy

0094475 Eglington近年来，分子有机代用品已成为古气候研究的一个组成部分。 至于其他代用指标，越来越需要从沉积物和冰芯中建立连续的、高时间分辨率的记录，以记录短期和长期的气候变化。 然而，通常情况下，有机地球化学测量落后于其他代用测量，部分原因是由于所涉及的费力的分析，因为相对较大的样本量的要求。 这项拨款提供部分资助，以购置一套克服现有限制的气相色谱/飞行时间质谱联用系统，新仪器的主要特点是以前所未有的速度获取全扫描质谱数据，为高灵敏度的快速样品分析铺平道路。 除了将其直接用作开发详细的高分辨率分子地层记录的工具外，我们还将配置GC/TOF-MS仪器用于两种新的分析模式。 第一个涉及从含水基质中吸附萃取有机化合物，随后通过热解吸单元引入样品。 我们计划使用这种方法测量冰芯样品中的痕量半挥发性有机物。 第二个涉及全面的二维气相色谱分离的GC配置。 后者能够详细描述高度复杂的地球化学基质。 总的来说，我们相信新仪器提供了独特的能力，将为古气候研究中分子有机代理的开发和应用开辟新的前沿。

0094475EglintonIn recent years, molecular organic proxies have become an integral component of paleoclimate research. As for other proxies, there is an ever-growing need to develop continuous, high temporal resolution records from sediment and ice cores to document short- and long-term climate variations. Typically, however, organic geochemical measurements lag behind other proxy measurements in part due to the laborious analyses involved, and because of relatively large sample size requirements. This grant provides partial support for the acquisition of a gas chromatograph/time-of-flight mass spectrometer (GC/TOF-MS) system that overcomes many of these present limitations.The key feature of the new instrumentation is the acquisition of full-scan mass spectral data at unprecedented rates, paving the way for very rapid sample analysis at high sensitivity. In addition to its direct application as a tool to develop detailed, high resolution molecular stratigraphic records, we will also configure the GC/TOF-MS instrument for two new modes of analysis. The first involves sorptive extraction of organic compounds from aqueous matrices and subsequent sample introduction via a thermal desorption unit. We plan to use this approach for the measurement of trace semi-volatile organic species in ice-core samples. The second involves configuration of the GC for comprehensive two-dimensional gas chromatographic separations. The latter enables detailed characterization of highly complex geochemical matrices. Overall, we believe the new instrumentation offers unique capabilities that will open up new frontiers for the development and application of molecular organic proxies in paleoclimate studies.***