Time-of-Flight Mass Spectrometry for Multidimensional Gas Chromatography and Related Fast-GC Techniques

该合同提供资金，用于购买一台飞行时间质谱仪(TOF-MS)，以增强现有的用于复杂有机混合物分析的研究系统。这种质谱仪使多维气相色谱(MDGC)和热梯度程序气相色谱(TGPGC)的研究得以继续。该设备提高了对燃烧残留物和废气以及其他类型的环境样品进行更快的GC-MS调查的能力。由于TOF-MS固有地比传统的四极杆或离子陷阱MS系统更快，因此有可能利用快速GC技术(如TGPGC)并将其整合到开发MDGC工作中。这大大增加了为正在进行的与燃烧废气、有机残留物和内分泌干扰化学品(EDCs)有关的工作所收集的信息。高速气相色谱本身就是一个不断发展和流行的研究领域。传统的开管柱(OTC)具有较小的内径，可用于高速GC分离。由于许多微孔OTC技术在样品溶质容量和检测极限方面存在严重缺陷，我们继续开发替代技术(如TGPGC)来进行不需要微柱和超灵敏检测器的高速GC。具有高溶质能力的快速GC系统有可能在燃烧系统中执行分析和过程控制，监测排放，并更快和更有效地执行常规或已建立的测试。然而，更快的GC分析最困难的方面是绝对需要更快响应的检测器。可以说，气相色谱最有用和最强大的检测器是质谱仪，因为它的灵敏度、特异度和识别能力。然而，由于它是一种扫描仪器，收集质谱图所需的时间与溶质区从色谱柱中洗脱的速度有关。因此，为了追求这些分析仪器的发展，需要一种在扫描速度上快几个数量级，但在灵敏度上与速度慢得多的四极杆和离子陷阱MS仪器相似的质谱计。飞行时间质谱仪(TOF-MS)可以在不牺牲灵敏度或定性能力的情况下提供这种类型的分析速度。更广泛的影响正在进行研究，以开发和使用多维气相色谱-质谱仪(MDGC-MS)来调查燃烧排放和残留物。通过从排放和残留物中识别尽可能多的成分，可以更准确地进行和解释风险评估。通常，使用双柱GC系统，其中操作主柱以最大化洗脱组分的分辨率，而操作辅助顺序柱以使得使用与主柱不同的固定相非常快速地分离剩余分析物。辅助通道内的快速GC是此分析的关键方面。

PROJECT SUMMARY This award provides funds to acquire a time-of-fight mass spectrometer (TOF-MS) to augment existing research systems for the analysis of complex organic mixtures. Such a mass spectrometer permits continuation of research involving development of multidimensional gas chromatography (MDGC) and thermal-gradient programmed gas chromatography (TGPGC). This equipment enhances the ability to develop faster GC-MS investigations of combustion residues and effluents, as well as other types of environmental samples. Because TOF-MS is inherently faster than conventional quadrupole or ion-trap MS systems, it is possible to exploit fast GC technologies (such as TGPGC) and integrate them into developing MDGC work. This greatly increases the information that can be gathered for ongoing efforts relating to combustion effluents, organic residues, and endocrine-disrupting chemicals (EDCs). High-speed gas chromatography is itself a growing and popular research area. Conventional open tubular columns (OTCs) that have small internal column diameters are available for high-speed GC separations. Since many microbore OTC techniques have significant shortcomings in sample solute capacity and detection limits, we continue to develop alternative techniques (such as TGPGC) to conduct high-speed GC that do not require microcolumns and ultra-sensitive detectors. Fast GC systems that possess high-solute capacity have the potential to perform analytical and process control in combustion systems, monitor emissions, and perform routine or established tests more quickly and efficiently. The most difficult aspect of faster GC analyses, however, is that faster-response detectors are absolutely required. Arguably, the most useful and powerful detector for gas chromatography is the mass spectrometer, due to its sensitivity, specificity, and identification ability. However, because it is a scanning instrument, the time required to collect mass spectral tracings is significant in relation to the speed at which a solute zone will elute from the chromatographic column. Therefore, what is needed in order to pursue the development of these analytical instruments is a mass spectrometer that is several orders of magnitude faster in scanning speed, and yet similar in sensitivity to much slower quadrupole and ion-trap MS instruments. Time-of-flight mass spectrometry (TOF-MS) can provide this type of analytical speed without sacrificing sensitivity or qualitative capability. Broader impactStudies are underway to develop and use multidimensional gas chromatography-mass spectrometry (MDGC-MS) to investigate combustion emissions and residues. By identifying as many components as possible from emissions and residues, risk assessments can be more accurately performed and interpreted. Typically, a two-column GC system is used in which a primary column is operated to maximize the resolution of coeluting components, while a secondary sequential column is operated such that remaining analytes are separated very quickly using a stationary phase dissimilar to the primary column. Fast GC within the secondary channel is the critical aspect of this analysis.