Panoptic electrochemical probe for next-generation mass spectrometry based-lipidomics

项目摘要/摘要 脂质在维持细胞功能方面起着至关重要的作用。脂代谢改变目前被认为是一个标志 许多疾病的特点，如恶性肿瘤，神经退行性疾病，心血管疾病， 还有糖尿病。这导致了对具有全面揭示血脂能力的新技术的需求 结构和组成。这种技术对于研究脂质结构-功能关系和 诊断和治疗病理学的方法的发展。基于质谱学的最新研究进展 脂类组学，包括离子活化法和化学衍生化，扩展了脂类的工具箱 分析。然而，目前还没有一种方法能够拆分所有类型的脂结构 因为脂类在结构上是多样化的，通常含有异构体的混合物。缺乏高效和可靠的 识别生物样品中的类脂异构体的分析方法直接导致了这样一个事实 类脂异构体的生理作用和功能在很大程度上仍不清楚。我研究的中心愿景是 计划是解决脂结构分析技术中的不足，使用独特的微滴 电化学(ME)方法，利用电压控制的脂类电化学衍生化 同分异构体和微滴界面处的电化学转化速度显著加快 实现结构上的阐明。建议的电压触发ME反应将在修改后的 采用探头形式的电喷雾发射器，并使用标准的商用MS仪器。派生的 产品将在串联质谱图中产生针对特定脂类异构体的诊断离子，从而 详细结构的表征。在接下来的五年里，我的研究小组的目标是开发ME探测器 用于脂质分析，特别强调异构体的鉴定和定量，以实现承诺 将ME作为了解、诊断和治疗疾病的实用研究工具。我的工具箱 将开发反应来表征各种脂类异构体，包括脂类，酰基链长，双- 键合位置、几何形状和sn(立体特定编号)-位置，需要的关键信息 脂类结构注释。ME反应是多样的，可以由电压变化触发，因此它们将 级联到单个系统(全景ME探针)以鉴定所有水平的异构体的脂类结构 单次实验中的特异性。ME探针将用于研究糖尿病前期患者的脂质体 小鼠心脏对西方饮食的反应揭示心脏中最初的脂类特征并定义 脂质异构体在心脏病理发展中的有害作用。这样做的预期结果是 该项目旨在提供一种广泛适用的方法，增强脂类结构分析的能力，该方法 将揭示脂类动态平衡中的结构-功能关系，以及当前脂类图谱所看不到的病理学。

PROJECT SUMMARY/ABSTRACT Lipids play a vital role in maintaining cellular function. Altered lipid metabolism is currently considered a hallmark characteristic of many diseases such as malignancies, neurodegenerative diseases, cardiovascular diseases, and diabetes. This has led to a demand for new technologies with comprehensive capabilities for revealing lipid structure and composition. Such technology is essential for the study of lipid structure-function relationships and the development of methods to diagnose and treat pathologies. Recent efforts in mass spectrometry (MS)-based lipidomics, including ion activation methods and chemical derivatization, have expanded the toolbox for lipid analysis. However, there is no single method at present that is capable of resolving all types of lipid structures since lipids are structurally diverse and often contain mixtures of isomers. The lack of efficient and reliable analytical approaches for discerning lipid isomers in biological samples directly leads to the fact that the physiological roles and functions of lipid isomers remain largely unknown. The central vision of my research program is to address the deficiencies in lipid structural analysis technology using the unique microdroplet electrochemical (ME) methods, which take advantage of voltage-controlled electrochemical derivatization of lipid isomers and the dramatically accelerated rates of electrochemical transformations at microdroplet interfaces to achieve structural elucidation. The proposed voltage-triggered ME reactions will be performed in a modified electrospray emitter taking the form of a probe and using standard commercial MS instrumentation. Derivatized products will generate diagnostic ions specific to particular lipid isomers in tandem mass spectra, allowing characterization of detailed structures. During the next five years, my research group aims to develop ME probes for lipid analysis with particular emphasis on isomer identification and quantification so as to realize the promise of ME as a practical research tool for understanding, diagnosing, and treating diseases. A toolbox of ME reactions will be developed to characterize various lipid isomers including lipid class, acyl chain length, double- bond positions, geometries, and sn(stereospecific numbering)-positions, the key information needed for accurate lipid structure annotation. The ME reactions are diverse and can be triggered by voltage changes, so they will be cascaded into a single system (a panoptic ME probe) to identify lipid structures at all levels of isomer specificity in a single experimental run. The ME probe will be used for studying the lipidome of pre-diabetic mouse heart to reveal the initial lipidomic signature in the heart in response to a Western diet and to define the deleterious effects of lipid isomers on the development of cardiac pathology. The expected outcome of this project is to provide a widely applicable approach with enhanced capabilities in lipid structural analysis, which will uncover structure-function relationships in lipid homeostasis and pathology invisible to current lipid profiling.