New Ion Mobility/Photodissociation Techniques for Analyzing Glycans

描述(申请人提供)：建议的研究旨在满足高优先级主题综合生物分子质谱学(03-DA-103*)对资助机会RFA-OD-09-003的要求。我们的目标是开发一种新的方法来鉴定葡聚糖异构体结构。这些结构最近被认为是表征疾病状态的可能标志。我们建议开发一种具有光解离能力的IMS陷阱。离子迁移率光谱(IMS)的最新发展包括被称为泛音迁移率光谱(OMS)的高分辨率方法的发展。OMS在将特定迁移率的离子从电喷雾电离(ESI)等连续电离源中分离出来的能力方面具有巨大的优势。在这里，我们建议将这种高分辨率分离技术与一种新的、高效的光裂解方法相结合，以增强对多糖异构体的识别。该仪器由一个与LTQ(ThermoScience)质谱仪耦合的OMS漂移管组成。质谱仪配备了一台F2激光器，可以用来诱导前体离子碎裂。高能碎裂(来自紫外线激发)和低能碎裂(来自CID)的组合提供了识别葡聚糖异构体的强大手段。这两种技术的协同作用为识别非常复杂的混合物中的物种提供了一种有效的方法。该提案中描述的方法非常适合于血清多糖的鉴定，因为其中许多是以各种异构体的形式存在的。考虑到碳水化合物在生物过程中的不同作用，拟议的研究的成功可能会对人类健康产生广泛的影响，从生物标记物的发现到分子水平上的衰老研究。 与公众健康相关：将建造一种新型的混合离子迁移率/线性离子陷阱质谱仪，具有表征复杂生物分子结构的独特能力。然后，它将被应用于从癌症患者血清中提取的原型糖链异构体和糖链的分析。

DESCRIPTION (provided by applicant): The proposed research is intended to satisfy the demands of the high priority topic Comprehensive Biomolecular Mass Spectrometry (03-DA-103*) for the funding opportunity RFA-OD-09-003. We aim to develop a new approach for identifying glycan isomer structures. These structures have recently been implicated as possible markers for characterizing disease states. We propose to develop an IMS-trap with photodissociation capabilities. Recent developments in ion mobility spectrometry (IMS) include the development of the high-resolution approach termed overtone mobility spectrometry (OMS). OMS offers tremendous advantages in its ability to isolate ions of specific mobilities from continuous ionization sources such as electrospray ionization (ESI). Here we propose to couple this high-resolution isolation technique with a new, high-efficiency photofragmentation method in order to enhance identification of glycan isomers. The proposed instrument consists of an OMS drift tube that is coupled to a LTQ (ThermoScientific) mass spectrometer. The mass spectrometer is outfitted with a F2 laser that can be used to induce precursor ion fragmentation. The combination of high-energy fragmentation (from UV excitation) with low-energy fragmentation (from CID) provides a powerful means of identifying glycan isomers. The synergy of the two techniques offers an effective method for identifying species in very complicated mixtures. The method described in the proposal is ideally suited for the identification of serum glycans as many of these exist as a variety of isomeric species. Considering the diverse role of carbohydrates in biological processes, the success of the proposed research could have wide impact on human health ranging from biomarker discovery efforts to studies of aging at the molecular level. PUBLIC HEALTH RELEVANCE: A novel hybrid ion mobility/linear ion trap mass spectrometer having unique capability for characterizing the structures of complex biomolecules will be constructed. It will then be applied to the analysis of prototype glycan isomers and glycans derived from the blood serum of cancer patients.