New Ion Mobility/Photodissociation Techniques for Analyzing Glycans

描述（由申请人提供）：拟议的研究旨在满足高优先级主题综合生物分子质谱（03-DA-103*）的资助机会RFA-OD-09-003的需求。我们的目标是开发一种新的方法来识别聚糖异构体结构。这些结构最近被认为是表征疾病状态的可能标志物。我们建议开发一种具有光解离能力的IMS陷阱。离子迁移谱（IMS）的最新发展包括称为泛音迁移谱（OMS）的高分辨率方法的发展。OMS在其从连续电离源如电喷雾电离（ESI）中分离特定迁移率的离子的能力方面提供了巨大的优势。在这里，我们建议耦合这种高分辨率的分离技术与一种新的，高效的光裂解方法，以提高识别的聚糖异构体。所提出的仪器由耦合到LTQ（ThermoScientific）质谱仪的OMS漂移管组成。质谱仪配备有F2激光器，可用于诱导前体离子碎裂。高能裂解（来自UV激发）与低能裂解（来自CID）的组合提供了鉴定聚糖异构体的有力手段。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。提案中描述的方法非常适合血清聚糖的鉴别，因为其中许多聚糖以各种异构体形式存在。考虑到碳水化合物在生物过程中的不同作用，拟议研究的成功可能对人类健康产生广泛影响，从生物标志物发现工作到分子水平的衰老研究。 公共卫生相关性：本文将研制一种新型的离子迁移率/线性离子阱混合质谱仪，该质谱仪具有独特的表征复杂生物分子结构的能力。然后将其应用于分析原型聚糖异构体和来自癌症患者血清的聚糖。

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.