New Advances in Multisegment Injection-Capillary Electrophoresis-Mass Spectrometry for Accelerating Biomarker Discovery in Metabolomics

代谢组学是一个以发现为基础的多学科研究领域，其目的是对生物样品中的低分子量代谢物（< 1.0 kDa）进行综合分析。由于代谢物是基因表达的真实终点，也反映了环境暴露，代谢组学为更好地理解复杂生物过程的机制提供了一种全面的方法。然而，存在一些“重大的分析挑战”，继续阻碍全球代谢组学计划的进展，包括低样品通量、低数据保真度、复杂的数据处理、有限的代谢组覆盖范围和未知的化合物鉴定。我们的研究项目将通过开发基于多段注射毛细管电泳-质谱（MSI-CE-MS）技术的尖端方法来克服这些障碍，该技术为代谢组学提供了一种具有高样品通量、严格质量控制和长期批量校正的变革性方法。我们的建议将极大地扩大代谢组的覆盖范围，以实现快速、敏感而稳健的分析，涵盖亲水代谢物和完整的磷脂，包括具有生物学意义的低丰度代谢物，如d -氨基酸、生物胺和维生素d。这将通过开发兼容的非水缓冲系统，结合化学选择性衍生化策略，同时使用新型纳米离子源来提高浓度敏感性来实现。由于质谱信息是在分离中临时编码的，因此将开发开放访问的软件工具，以实现MSI-CE-MS数据的自动化处理，与传统的LC-MS， GC-MS和NMR平台相比，MSI-CE-MS数据在吞吐量，再现性和数据保真度方面无与伦比。此外，将研究溶剂化离子的电泳迁移率及其气相电离反应的基础研究，以研究不同类别的代谢物，作为进行虚拟代谢组学研究的一种方式；在缺乏化学标准和质谱数据库不完整的情况下，这项工作将提供一种创新的策略，基于其假定的化学结构来识别和量化未知代谢物，与高分辨率MS/MS相补充。我们的研究项目还将使用最先进的MSI-CE-MS方法，应用于基于粪便代谢组特征的人类微生物组的功能分析，以及从体积受限的生物标本中识别与消防员烟雾暴露相关的新化学特征，包括使用非侵入性收集设备的汗液。这一及时的提案将为生物标志物的发现提供突破性的分析技术、集成的软件工具和加速的数据工作流程，以支持全球代谢组学计划，这些计划也具有强大的商业潜力，对加拿大的公共政策有直接影响。

Metabolomics is a multidisciplinary area of discovery-based research whose aim is the comprehensive analysis of low molecular weight metabolites (< 1.0 kDa) in biological samples. Since metabolites are real-world endpoints of gene expression that also reflect environmental exposures, metabolomics offers a holistic approach to better understand the mechanisms underlying complex biological processes. However, there exists several "grand analytical challenges" that continues to hinder progress in global metabolomics initiatives, including low sample throughput, poor data fidelity, complicated data processing, limited metabolome coverage, and unknown compound identification. Our research program will overcome these obstacles by developing cutting-edge methodologies based on multisegment injection capillary electrophoresis-mass spectrometry (MSI-CE-MS) technology that offers a transformative approach to metabolomics with high sample throughput, stringent quality control and long-term batch-correction. Our proposal will greatly expand metabolome coverage to enable rapid, sensitive yet robust analyses spanning hydrophilic metabolites and intact phospholipids, including low abundance metabolites of biological significance, such as D-amino acids, biogenic amines, and vitamin D. This will be achieved by developing compatible nonaqueous buffer systems in conjunction with chemoselective derivatization strategies while using a novel nanospray ion source to boost concentration sensitivity. Since mass spectral information is encoded temporally within a separation, open-access software tools will be developed to enable automated processing of MSI-CE-MS data that is unsurpassed in throughput, reproducibility, and data fidelity as compared to conventional LC-MS, GC-MS and NMR platforms. Also, fundamental studies of the electrophoretic mobility of solvated ions and their gas-phase ionization responses will be investigated for diverse classes of metabolites as a way to conduct virtual metabololomic studies; this work will provide an innovative strategy to identify and quantify unknown metabolites based on their putative chemical structure complementary to high resolution MS/MS when chemical standards are lacking, and mass spectral databases remain incomplete. Our research program will also use state-of-the-art MSI-CE-MS methods as applied to the functional analysis of the human microbiome based on characterization of the fecal metabolome, as well as the identification of new chemical signatures associated with smoke exposure in firefighters from volume-restricted biospecimens, including sweat using a non-invasive collection device. This timely proposal will deliver groundbreaking analytical technology, integrative software tools, and accelerated data workflows for biomarker discovery in support of global metabolomic initiatives that also has strong commercial potential with direct impacts on public policy in Canada.