Time of Flight Mass Spectrometer for GC-based analysis of small molecules

小分子分析是评估生物学机制的组成部分，可以是靶向的或非靶向的。对于靶向分析，通过针对靶分子优化色谱和检测条件来实现特定分子的绝对或相对定量。相比之下，非靶向分析平衡了次优色谱分离与高分辨率质量分析，导致基于质量的信息解卷积。飞行时间（ToF）质谱仪提供高分辨率的质量精度（约100%）。1 ppm），从而可以对色谱分离较差的复杂样品混合物进行去卷积。它们适用于各种分子类别的常规GC-MS分析，因为它们可以生成高分辨率的精确质谱和EI质谱，可以与已发表的数据进行比较。GC-TOF-MS代表了初级代谢物非靶向（代谢组学）分析的行业标准。在本提案中强调的所有研究计划中，通过靶向或非靶向方法分析小分子是解决更大生物学问题的一个组成部分。例如，GC-ToF-MS系统将用于（1）使用小鼠视网膜模型发现神经变性中改变的初级代谢的生物标志物，（2）从番茄中鉴定用于控制叶螨侵染的潜在生物农药，（3）在生物多样性的土壤模型中通过不同营养水平跟踪碳的流动，了解植物对重金属土壤污染物的防御，（4）了解在未来气候条件下生长的树木中碳水化合物的动态;（5）确定创伤诱导的马铃薯块茎中的碳通量。这些基础和应用项目反映了广泛的主题，所有这些都具有需要小分子分析以帮助建立潜在机制的共同特征，从而更深入地了解系统。

Small molecule analysis is an integral component of assessing biological mechanisms and can be either targeted or non-targeted. For targeted analysis, absolute or relative quantitation of specific molecules is achieved by optimizing chromatographic and detection conditions to the target molecules. In contrast, non-targeted analyses balance suboptimal chromatographic separation with high resolution mass analysis leading to informative mass-based deconvolution. Time of flight (ToF) mass spectrometers offer high resolution mass accuracy (approx. 1 ppm) allowing deconvolution of complex sample mixtures that are poorly resolved by chromatography. They are suitable for routine GC-MS analysis of a wide range of molecule classes, since they can generate high resolution accurate mass and EI mass spectra that can be compared with published data. GC-TOF-MS represents the industry standard for non-targeted (metabolomic) analysis of primary metabolites. In all the research programs highlighted in this proposal, the analysis of small molecules through either targeted or non-targeted approaches forms an integral part of the solution to larger biological questions. For example, the GC-ToF-MS system will be used to (1) discover biomarkers of altered primary metabolism in neurodegeneration using a mouse retina model, (2) identify potential biopesticides from tomato for the control of spider mite infestation, (3) track the flow of carbon through different trophic levels in a soil model of biodiversity, understand plant defenses against heavy metal soil contaminants, (4) understand carbohydrate dynamics in trees grown under future climate conditions and (5) determine the carbon flux in wound-induced potato tubers. These basic and applied projects reflect a broad range of topics, all with the common feature of requiring small molecule analysis to help establish underlying mechanisms, and thereby deeper understanding of the systems.